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05383d9075e345a323cb3dfd39b55815 | 101 274 | 9.1 General characteristics | FH-CDMA systems share the frequency resource between radio links by use of multiple frequency slots, while providing each link with access to the entire allocated bandwidth. Each frequency slot is occupied by a carrier modulated with the data rate (including FEC if necessary) wanted by a certain subscriber, however the centre frequency of that carrier changes in time (hops). The "hopping sequence" is the "code" associated with each link and the assignment of different codes for different links in the same vicinity means that the system is a Code Division system. The most common FH-CDMA nowadays are SFH (where the hopping rate is less then the symbol rate). This is a spread spectrum technique which when applied to Radio Local Loop systems, switches individual subscriber channels when in use, from frequency to frequency to minimize the effects of fading and narrowband interference. Fast frequency hopping systems, with hopping rate faster than the symbol rate, can also be found. This type of hopping provides many more samples per symbol and enables non-orthogonal operation, where several users may occupy the same frequency slot in the same time. Presently, commercially available P-MP fast frequency hopping systems do not exist, and the relevant standards do not refer to them. The following analysis refers only to orthogonal SFH-CDMA systems. From the point of view of the occupied spectrum these systems are very similar to FDMA. Most of the features described in subclause 6.1 apply also to FH-CDMA. On the other hand, being a fully synchronized system it is very similar to TDMA. Frequency planning is very similar to that applied to these systems. However, from the point of view of the user, the system is similar to DS-CDMA, as it uses the entire bandwidth and thus provides the benefit of spread spectrum communication, namely interference suppression, robust radio link and inherent security. FH can be applied to other techniques like DS-CDMA, TDMA and FDMA by dividing the instantaneous (hop) radio channels in the DS-CDMA code domain, by a further division in the time domain with TDMA techniques or by dividing the hop bandwidth to a number of sub-carriers (frequency slots) when a FDMA technique is used (Multicarrier approach). Forward error correction, interleaving and erasure enable frequency band reuse in adjacent cells with a re-use factor of one in fixed applications. ETSI TR 101 274 V1.1.1 (1998-06) 34 A standard channel arrangement is to use one partial RF-band for downlink transmission from the CRS to the TS and another partial band (normally but not necessarily of the same bandwidth) for uplink transmission from the TS to the CRS. The separation of Tx- and Rx-band in both CRS and TS by a sufficiently large duplex spacing allows to control interference between CRSs and between TSs so that this type of distortion can be neglected when planning cellular configurations. Another typical arrangement is to share the same channel by both the CRS and the TS, but to separate them in time. With proper synchronization, which is intrinsic in FH-CDMA systems, this time-domain separation allows a very good control of interference between CRSs and TSs. |
05383d9075e345a323cb3dfd39b55815 | 101 274 | 9.2 Isolated performance for FH-CDMA | In the following the FH-CDMA capacity and the minimum power level in threshold condition Sav will be derived assuming absence of interfering cells and LOS. The bandwidth of a modulated carrier is given by the relation: ( ) ( ) B R R R ld M r C b OH = + × × + ( ) 1 (34) where: Rb: information bit rate; ROH : Overhead bit rate for hopping and synchronization; R: code rate (R≤1); ld(M): base 2 logarithm of number of levels M of the modulated carrier; r: roll-off factor or roll-off equivalent spacing factor for adjacent hop carriers (assumed to be 0,2). System capacity within a RF-channel of bandwidth BRF, characterized by the number N of channels transmitting bit rate Rb is given by: N B B RF C = (35) The minimum average power level in threshold condition Sav can be calculated by means of the same relation which holds for TDMA, FDMA: ( ) ( ) S E N R kT F av b dB b dB = + × + × + 0 0 10 10 log log (36) Eb/N0: bit energy to noise spectral density ratio (see table 5 and table 12); K = 1,38 × 10-23 J/K: Boltzmann constant; T0 = 293 K: environmental temperature; Rb : user bit rate; FdB = 6 dB: noise figure. Table 14 shows the sensitivity for various modulation and coding schemes and for several values of bit rates expressed in kbit/s. ETSI TR 101 274 V1.1.1 (1998-06) 35 Table 14: System sensitivity as a function of modulation and coding schemes and data bit rates with ROH equal 16 kbit/s Sav @BER =10-3 (dBm) Sav@ BER = 10-6 (dBm) Mod. Rb = 64 Rb = 128 Rb = 384 Rb = 2048 Rb = 64 Rb = 128 Rb = 384 Rb = 2048 QPSK(1/2) -116 -113 -109 -101 -113 -111 -106 -99 QPSK(3/4) -115 -112 -108 -100 -112 -110 -105 -98 QPSK(1) -110 -108 -103 -96 -107 -104 -100 -93 8PSK(2/3) -114 -111 -107 -99 -111 -109 -104 -97 16PSK(3/4) -108 -106 -101 -94 -106 -104 -99 -92 When FSK modulation is used, the system sensitivity is shown in table 8. |
05383d9075e345a323cb3dfd39b55815 | 101 274 | 9.3 Cellular deployment performance for FH-CDMA system | As stated in subclause 4.5, cellular deployment means that a certain number of frequencies are reused in other cells (or sectors) properly distanced. This means that a certain amount of co-channel interference has to be taken into account during link budget calculation. The presence of co-channel interference causes an increment of the power threshold level because it acts like an additional noise power at the input of the receiver. In this context, relation (4) can be evaluated by adding a contribution for each cell (or sector) working at the same frequency on the basis of subclause 4.5 rules. Supposing the interference as a gaussian noise, a general figure on power threshold level with co-channel interference can be evaluated by means of the following equation: ( ) ( ) ( ) S E N Log R Log KT F Log E N R W I C av dBm b dB b dB b b TOT = + × + × + − × − 0 0 0 10 10 10 1 (37) where C I TOT is the overall signal to interference ratio expressed by relation (4). At any rate, the best way to evaluate this figure is by means of measured sensitivity curves provided by the manufacturers. 10 Impact on performance and capacity due to CRS and TS antenna In subclause 4.5 a very simple methodology has been provided in order to calculate the overall C/I for a given frequency reuse environment. That methodology is based on the assumption that all the users are located in the worst interfering site. However, this hypothesis could lead to a pessimistic C/I estimation and, in addition, does not show how the TS antenna influences the C/I related to the different frequency reuse environment. In order to investigate these issues it has become necessary to perform simulations: the user traffic in each of the six cells surrounding the cell under analysis has been modelled in order to estimate the interference statistics. TS antennas have been considered: figure 5 shows a typical antenna characteristics for 1 GHz to 3 GHz bands, and figure 6 show a typical antenna characteristics for 10,5 GHz band. In addition, three frequency reuse environment has been considered with six surrounding cells as shown, for M = 1, in figure 2. In particular, the following assumptions have been made: • six surrounding interfering cells; • P-MP system with 32 64 kbit/s channels for each cell; • uniform users distribution over the interfering cells; • CRS with omnidirectional antenna; • poisson traffic model; ETSI TR 101 274 V1.1.1 (1998-06) 36 • mean call duration = 100 s; • traffic per cell with GOS = 1 %; • perfect power control and all interfering links with the same modulation scheme; On the basis of the previous assumptions, the following case studies have been considered: • access schemes: TDMA, DS-CDMA, FDMA and FH-CDMA; • M = 1, M = 3 and M = 4; • antenna patterns as in figure 5 and figure 6; • propagation exponent for the useful links: γ = 2 ; • propagation exponent for the interfering links: γ = 2 and γ = 3. The results for several case studies are shown in figures 7 to 14 in terms of the cumulative distribution functions of the overall C/I. In particular, each curve shows, for a given C/I value, the probability of having a lower C/I value. In other words, for a given C/I, each curve provides, for the relevant case study, the percentage of time in which a lower C/I value could be expected. As an example, a C/I with a probability equal to 10-3 means that we could expect to have a lower C/I for about 45 minutes during a month with 31 days. In addition it could be easily found that the usage of a more directive antenna (see figure 6) makes it possible to gain 2 dB on the overall C/I for TDMA, FDMA, FH-FDMA and 4 dB for DS-CDMA. In order to explain better how to use the results provided by the figures below, two examples shall be analysed: one for DS-CDMA and one for TDMA access scheme. Cellular deployment for Pseudo Random DS-CDMA can be analysed by means of relation (27). Looking at figure 7, we can read a C/I value of -4,5 dB for a M = 1 and with a probability equal to 10-3. By using this value in (27) instead of the term: ( ) C I C I i i N Y tot = − = × ∑ 1 1 1 / (38) It is possible to find out a degradation in capacity lower than 10 %. It is worth noting that by means of relation (28), the relevant figures for Pseudo Random DS-CDMA can be used also for analysing Orthogonal DS-CDMA cellular deployment. As far the TDMA, FDMA and FH-CDMA access schemes are concerned, cellular deployment can be analysed by means of relation (20). Looking at figure 13, we can read a C/I value of 16,8 dB for a M = 4 and with a probability equal to 10-3. Using this value in (20) instead of the term (C/I)tot , it is possible to find out the feasibility of this cluster size, even with uncoded transmission, for the area of deployment in which the interfering link have a propagation exponent γ = 3 (e.g. rural application). ETSI TR 101 274 V1.1.1 (1998-06) 37 -40 -35 -30 -25 -20 -15 -10 -5 0 -180 -135 -90 -45 0 45 90 135 180 Degree Gain/G(0) Figure 5: RPE for 1 GHz to 3 GHz bands -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 0 -180 -135 -90 -45 0 45 90 135 180 Degree Gain/G(0) Figure 6: RPE for 10,5 GHz band ETSI TR 101 274 V1.1.1 (1998-06) 38 1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+00 -6 -4 -2 0 2 4 6 C/I [dB] Probability M=1 M=3 M=4 Figure 7: C/I cumulative distribution function for Pseudo Random DS-CDMA with antenna in figure 5 and interfering propagation exponent γ = 2 1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+00 -2 0 2 4 6 8 10 12 C/I [dB] Probability M=1 M=3 M=4 Figure 8: C/I cumulative distribution function for Pseudo Random DS-CDMA with antenna in figure 6 and interfering propagation exponent γ = 2 ETSI TR 101 274 V1.1.1 (1998-06) 39 1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+00 -2 0 2 4 6 8 10 12 14 C/I [dB] Probability M=1 M=3 M=4 Figure 9: C/I cumulative distribution function for Pseudo Random DS-CDMA with antenna in figure 5 and interfering propagation exponent γ = 3 1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+00 2 4 6 8 10 12 14 16 18 C/I [dB] Probability M=1 M=3 M=4 Figure 10: C/I cumulative distribution function for Pseudo Random DS-CDMA with antenna in figure 6 and interfering propagation exponent γ = 3 ETSI TR 101 274 V1.1.1 (1998-06) 40 1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+00 2 4 6 8 10 12 14 16 18 C/I [dB] Probability M=1 M=3 M=4 Figure 11: C/I cumulative distribution function for TDMA, FDMA and FH-CDMA with antenna in figure 5 and interfering propagation exponent γ = 2 1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+00 4 6 8 10 12 14 16 18 C/I [dB] Probability M=1 M=3 M=4 Figure 12: C/I cumulative distribution function for TDMA, FDMA and FH-CDMA with antenna in figure 6 and interfering propagation exponent γ = 2 ETSI TR 101 274 V1.1.1 (1998-06) 41 1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+00 7 9 11 13 15 17 19 21 23 25 C/I [dB] Probability M=1 M=3 M=4 Figure 13: C/I cumulative distribution function for TDMA, FDMA and FH-CDMA with antenna in figure 5 and interfering propagation exponent γ = 3 1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+00 9 11 13 15 17 19 21 23 25 27 C/I [dB] Probability M=1 M=3 M=4 Figure 14: C/I cumulative distribution function for TDMA, FDMA and FH-CDMA with antenna in figure 6 and interfering propagation exponent γ = 3 ETSI TR 101 274 V1.1.1 (1998-06) 42 Annex A: Propagation measurements for ad-hoc deployment A.1 Method A number of propagation measurement campaigns have been carried out for ad-hoc deployment in UK and Finnish cities in the 3,4 GHz band. In general, the method used was as follows. Transmitters were set up at typical CS locations chosen to illuminate the desired area. Transmitting antennas were either omnidirectional or "sectored"; for an omnidirectional antenna the typical gain was 10 dBi (achieved by the narrow vertical beamwidth). Somewhat higher gains are achievable with sectored antennas. Vertical polarization was used throughout. The radiated carrier was unmodulated, allowing the use of narrow receiver bandwidth to maximize dynamic range. Received signal levels were measured at a vehicle equipped with a telescopic mast, at a large number of randomly chosen locations. The receiving antenna mounted on the mast was pointed at the CS location from each measurement point and the mast set to rooftop height to measure the signal level. The level was measured over a period of time to assess the variability of the signal. The receiving antenna gain was 18 dBi. With the transmit power and receiver bandwidth used the total dynamic range possible was approximately 180 dB. Separate tests have been done to characterize multipath propagation using wideband channel sounding and swept frequency measurements in cities in both the UK and Finland. A.2 Results Figure A.1 plots the measured path loss from one typical trial. For each measurement location, the median path loss and the path loss exceeded for 99 % of the measurement period are shown, as a function of the range of the point from the CS location. Also plotted is the free space path loss. Figure A.1: path loss measurements The results clearly show the large excess loss and variability expected when a LOS path cannot be guaranteed. It is obvious that the maximum possible system range will be required to maximize the probability of providing service at any particular point from the given CS. ETSI TR 101 274 V1.1.1 (1998-06) 43 Multipath measurements have also shown that delay spread is found on a proportion of paths, with a maximum recorded delay spread of up to 4 µs. The existence of multipath at any given TS location is unpredictable, and to maximize the service probability the system has to cope with this level of delay spread. For P-MP systems in frequency bands at or above 10 GHz, line-of-sight conditions are an inevitable condition for each link. On the one hand this reduces coverage, because a prospective TS location can no longer be supplied by means of the physical effects of reflection or diffraction. This negative effect has to be taken into account. On the other hand the highly positive effect is a strong reduction of dynamic range of receive power in any CRS or TS. This is in contrast to the measurement results discussed above. In particular the impact of multipath transmission is reduced drastically because these unintended paths depend on reflection and/or diffraction and can be assumed to show considerably higher path loss than the wanted line-of-sight path. Hence all the negative effects of multipath propagation such as Intersymbol Interference and loss of power will be reduced in the higher frequency bands. ETSI TR 101 274 V1.1.1 (1998-06) 44 History Document history V1.1.1 June 1998 Publication ISBN 2-7437-2219-3 Dépôt légal : Juin 1998 |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 1 Scope | The purpose of the present document is to describe the functionality of a Multiband GSM/DCS Network operated by a single operator and the Multiband GSM/DCS Mobile Station (MS). It also describes the necessary amendments to the GSM/DCS phase 2 specifications for the technical realization of the function. The resulting Amendment Requests (AR) and Change Requests (CR) necessary for Multiband Operation are listed in annex A. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 1.1 References | Not relevant to the present document. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 1.2 Abbreviations | Abbreviations used in the present document are listed in GSM 01.04. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 2 General | Multiband operation of GSM/DCS by a single operator enables an operator, with licenses in more than one of the frequency bands specified in the GSM specifications, to support the use of multiband MSs in all bands of the licenses. In addition it also enables the operator to support the use of single band MSs in, at least, one band of the licenses. Multiband GSM/DCS MSs, are MSs which are capable of using more than one of the frequency bands specified in the GSM specifications. The multiband MS is specified in GSM 02.06. (AR02.06-A001) and in section 2.1. The use of multiband operation and development of multiband MSs are optional for operators and manufactures. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 2.1 Multiband MSs | A MS which supports more than one band and the functionality below is defined as a Multiband MS. The multiband MS has the functionality to perform handover, channel assignment, cell selection and cell re-selection between all its bands of operation within one PLMN, i.e. when one PLMN code is used in all bands. In addition it has the functionality to make PLMN selection, in manual or automatic mode, in all its bands of operation. The multiband MS shall meet all requirements specified for each individual band supported. In addition it shall meet the extra functional requirements for the multiband MSs. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 2.2 Frequency bands of operation | Multiband operation shall be possible with any combination of the frequency bands specified in the GSM specifications. No frequency band is treated as a primary band in the specification. The operators may however use control mechanisms to make the MSs treat one of the bands with priority. As a first implementation of Multiband operation only operation with GSM 900 (Standard or Extended) and DCS 1 800 is included in the standard. The proposed procedures shall however make it possible for operation between other bands if such are included in the core specifications in the future. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 2.3 Backwards compatibility | Backwards compatibility with phase 1 and phase 2 single band mobiles shall be ensured by the specification of multiband operation. A multiband PLMN shall therefore, in addition to support of multiband MSs, be able to support the use of single band mobiles for, at least one of the bands of operation. ETSI ETSI TR 101 266 V8.0.0 (2000-04) 6 (GSM 03.26 version 8.0.0 Release 1999) Backwards compatibility by the multiband MSs shall also be ensured. The MSs shall therefore be able to, functionally, work as single band mobiles in a single band network. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 2.4 PLMN codes | Multiband operation of GSM/DCS by a single operator, with handover and assignment between the bands, implies that only one PLMN code is used in all bands of operation. Handover or assignment between PLMNs is not covered by this document or the work item. An operator, with license in more than one band, may however support multiband mobiles without handover and assignment between the bands. If so, more than one PLMN code may be used. This is already covered with the phase 1 and phase 2 specifications. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 2.5 Other systems | Multiband operation by a single operator does not include multi mode operation, i.e. handover, assignment or roaming between GSM/DCS and systems covered by other specifications or standards. The amendments of the GSM/DCS specifications for multiband operation may however be done in a flexible way so that multi mode operation can make use of the same procedures. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 3 Requirements | |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 3.1 User requirements | No special actions by the user shall be necessary to use a multiband MS. The possibility for the user to decide to operate the MS in a single band mode may however be supported. Indications may also be given to the user of which band is being used. The user of a multiband MS shall be able to roam between PLMNs operating in any of the MS's frequency bands of operation. The MS shall therefore, at PLMN selection, present all available PLMNs within its frequency bands of operation. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 3.2 Operator requirements | The use of multiband operation shall be optional for the operator. Multiband MSs must therefore be able to, functionally, work as single band MSs in a single band network. When multiband operation is used, it shall be possible to provide coverage in one frequency band independently of the coverage in another band.. Two options can be implemented by an operator when operating a multiband network : i) a BCCH in each band of operation; ii) a common BCCH in only one of the band of operation when resources across all bands are co-located and synchronized. NOTE: For case ii), in order to ensure proper operation of the network, the operator should take into account issues related to the difference of propagation between the different bands, e.g GSM and DCS when performing cell planning. As far as synchronization issues are concerned, the requirements for TA for multiband BTSs may only be fulfilled when the TA is the same in the two bands, i.e. within the tolerance as defined in GSM 05.10. This imposes some restrictions on the cells where the two bands are supported (e.g. small cells). ETSI ETSI TR 101 266 V8.0.0 (2000-04) 7 (GSM 03.26 version 8.0.0 Release 1999) |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 3.3 Radio requirements | The radio requirements for GSM and DCS in the present GSM/DCS specification differs in some cases. A multiband MS and the multiband network shall meet all requirements for each band of operation respectively. Type approval of multiband MSs will be covered by the respective test specifications and some additional tests for the multiband functionality. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 3.4 Relation to frequency hopping | The multiband MS and the multiband network shall support frequency hopping within each band of operation. Frequency hopping between the bands of operation is not required. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 4 Functional description | To understand the necessary amendments of the phase 2 specifications functional descriptions of different procedures and solutions are described below. The technical realization are described in clause 5 and the actual amendments are listed in annex 1 with a brief description. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 4.1 Idle mode procedures | The idle mode procedures will not be different for multiband MSs or networks. Only the fact that more than one band is available has to be taken into account. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 4.1.1 PLMN selection | A multiband MS shall use the normal PLMN selection procedures, as specified in GSM 02.11 and 03.22, with the additional requirement to select from all available PLMNs in all bands of operation. When presenting available PLMNs it shall show all available PLMNs within the MSs bands of operation. A multiband PLMN may have BCCHs available on more than one band but shall still be treated as one PLMN and must therefore only be presented once. PLMN search time, at switch on, will be the sum of the search times presently specified for each band of operation if no prior knowledge is stored in the MS. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 4.1.2 Cell re-selection | The multiband network will send out neighbour cell lists which may contain a mixture of channels from different frequency bands. The multiband MSs shall follow the normal cell-re-selection procedures with the addition to monitor all channels within the neighbour cell list which are within the MS's bands of operation. All MSs shall ignore channel numbers which are outside its bands of operation. Channels within the MS's bands of operation shall be monitored. Priority at cell re-selection can be given to one of the bands of operation by using existing phase 2 parameters. Compatibility with phase 1 and phase 2 MSs will be ensured by the procedures described in clause 6. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 4.1.3 Location areas | No special requirements are specified for the allocation of location areas among the cells in a multiband network. It shall therefore be possible the use the same or different location areas for cells in different frequency bands irrespective of their location. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 4.2 Connected mode procedures | The multiband network will send out neighbour cell lists which may contain a mixture of channels from different frequency bands. The multiband MS shall use the normal monitor and reporting procedures with the additional requirement to monitor and report from all channels within its bands of operation. ETSI ETSI TR 101 266 V8.0.0 (2000-04) 8 (GSM 03.26 version 8.0.0 Release 1999) |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 4.3 Handover | Based on the measurement reports sent by the multiband MS the network will send handover commands to any channel within the MS's bands of operation. To ensure that handover is possible to a cell which was not reported to be the strongest candidate, e.g. for traffical reasons, a multiband MS shall report at least the number of strongest candidates on each band measured and identified as indicated by the parameter Multiband_Reporting sent in System Information 2ter/5ter. The coding of this parameter is specified in AR 05.08-A006. Any MS will only send measurement reports from cells within its bands of operation. Handover commands to cells outside the bands of operation will therefore not occur.. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 4.4 Frequency and power capabilities | The network will be informed by the MS of its frequency and power capabilities to ensure that all procedures, e.g. the handover algorithm, gets accurate information. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 5 Technical realization and amendments | The technical realization, e.g. bit mapping, is described in this clause. Also, the necessary amendment is described and reference is made to the amendment request presented. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 5.1 Mixed neighbour cell lists | A multiband network may use System Information 2/5, System Information 2bis/5bis and a new System Information 2ter/5ter to inform the MSs about the available neighbour cell frequencies. The BCCH channel list consists either of only the sub list derived from the neighbour cell description information element(s) in SI 2/5 (and possibly SI 2bis/5bis) or that sub list concatenated with the neighbour cell description information element received in SI 2ter/5ter in case SI 2ter/5ter is also received. Indication that 2ter is available is included in the SI3 rest octets. Channel numbers which are outside the bands of operation of a MS will be ignored. The scheduling of the sending of SI 2ter on BCCH is specified in AR05.02-A001. Solution to problems with backwards compatibility are described in clause 6. Different encoding of the BCCH frequencies in the BA list give different numbers of possible combinations and number of neighbour cells in the list. The limitations are given below: 1024 range This allows to encode 2 - 16 frequencies, the frequencies being spread among up to 1024 ARFCNs. This cover more than P-GSM, E-GSM and DCS 1800 together. 512 range This allows to encode 2-18 frequencies, the frequencies being spread among up to 512 consecutive ARFCNs. This would cover the E-GSM and DCS for instance. 256 range This allows to encode 2-22 frequencies, the frequencies being spread among up to 256 consecutive ARFCNs. 128 range This allows to encode 2-29 frequencies, the frequencies being spread among up to 128 consecutive ARFCNs. Variable bit map This allows any combination among 112 consecutive ARFCNs. Bit map 0 This allows to encode 124 frequencies among ARFCNs 1-124. ETSI ETSI TR 101 266 V8.0.0 (2000-04) 9 (GSM 03.26 version 8.0.0 Release 1999) |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 5.2 Frequency and power capabilities | The network has to be informed of the frequency capabilities and the associated power capability of the multiband MS, on each frequency band, at call set up to ensure a reliable functionality. A multiband mobile shall therefore send a classmark change message with CM3 information as early as possible according to the procedure described in AR 04.08-A069 and AR 04.08-A071 (Early Classmark Sending). In order to give an early indication to the network that the MS is capable of using the Early Classmark Sending, one bit in CM1 and CM2 is used (the spare bit in front of the A5/1 bit). The network may forbid the MS to use Early Classmark Sending by setting the Early Classmark Sending Control (ECSC) bit in the SI3 rest octets to "L". The requirement on the timing of the Classmark Change message, such that the MS send CM change in the empty uplink block following the reception of the L2 UA frame, is specified in AR 04.13-A001. An operator may decide to delay or inhibit the sending of the Classmark Change message from the BSC to the MSC if it was received immediately after the initial L3 message. This is described in AR08.08-A013. Any combination of frequency bands and power capabilities in the GSM specifications shall be possible. The coding of frequency and power capabilities according to the solution in AR04.08-A007 ensure this flexibility and also give room for further evolution. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 5.3 Measurement reports | The multiband MS will normally report the signal strength of six strongest and identified neighbour cells as a normal MS. These cells may however not use the same frequency band. To ensure that handover is possible, e.g. for traffical reasons, to a cell which was not reported to be the strongest candidate, a multiband MS shall, for each band, report at least the number of strongest candidate cells measured and identified as indicated by the MultibandReporting parameter. This parameter is sent in the 5ter and 2ter messages with two bits from the Skip Indicator, which will not be used in 2ter/5ter. The maximum of six cells reported is still unchanged. The sending of the MultibandReporting parameter is specified in AR04.08-A015.The coding of the two bits in the parameter is specified in AR 05.08-A006. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 6 Backwards compatibility | Multiband operation will be specified to be backwards compatible so that no harm is made to existing networks and that phase 1 and phase 2 single band mobiles will work in a multiband network. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 6.1 Support of single band operation | |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 6.1.1 Single band MSs | A multiband network will normally support single band mobiles in each of the bands of operation but in some cases (common BCCH in one band), it will only support single band mobiles in one of the bands of operation. Single band signalling will be present as well as multiband signalling. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 6.1.2 Single band networks | The multiband MSs will, functionally, work as single band mobiles in a single band network. ETSI ETSI TR 101 266 V8.0.0 (2000-04) 10 (GSM 03.26 version 8.0.0 Release 1999) |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 6.2 Mixed neighbour cell lists | |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 6.2.1 Phase 1 MSs | Some phase 1 DCS mobiles ignores the whole BA list if frequencies outside the DCS band is contained in the BA list. System Information 2ter/5ter are therefore introduced to solve this problem. In multiband PLMNs, where phase 1 DCS MSs will be present, SI 2ter/5ter will be used to indicate the ARFCNs outside the DCS1800 band. SI 2ter/5ter will then be ignored by the phase 1 MSs but SI2/5 and 2bis/5bis will still be used. |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 6.2.2 Phase 2 MSs | Phase 2 mobiles will only ignore channel numbers, i.e. not the whole BA list, which are outside the bands of operation of the MS. This is already included in the phase 2 specifications (CR-04.08-665). 6.3 Detected compatibility problems and their solutions (when possible) |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 6.3.1 New messages on the BCCH | Some GSM 900 phase 1 mobiles will not operate properly if new SI messages with a L2 pseudolength greater than 1 are received. To be able to provide service to these mobiles in a multiband 900-1800 network with P-GSM 900 phase 2 mobiles, the handling of the pseudolength received in SI messages have been modified and some measures to avoid the situation have been defined in ETR 09.94. The changes introduced are: - Phase 2 mobiles are recommended to ignore the L2 pseudolength received in all SI messages. For the System Information 2ter message mobiles are required to ignore the received L2 pseudolength. (CR -04.08-A239 rev 2 and 238 rev 2) - Networks shall set the L2 pseudolength in the SI 2ter message to 0. SI 2bis must not be used in the P-GSM band. (CR -09.94-A007 rev 1) |
90cad3edd49bc9640b419aa9fa308dfd | 101 266 | 6.3.2 New messages on the SACCH | Some phase 1 mobiles may experience performance degradations if the network sends SI messages not defined in phase 1 on the SACCH. The recommended measures to avoid this degradation have been defined in ETR 09.94 (CR -09.94- A007 rev 1): - Networks shall not send SI 5ter messages on the SACCH to phase 1 GSM or DCS mobiles or SI 5bis messages on the SACCH to phase 1 GSM mobiles. ETSI ETSI TR 101 266 V8.0.0 (2000-04) 11 (GSM 03.26 version 8.0.0 Release 1999) Annex A (informative): List of amendments necessary A.1 Approved by TC SMG for Phase 2 A.1.1 CR-04.08-665 on mixed frequency lists Compatibility ensured for phase 2 mobiles in a multiband PLMN. A.2 Approved by TC SMG and put on HOLD A.2.1 AR 08.58-A005r4 "Sending of SACCH System Information on a call-by-call basis" Procedures to send SI on SACCH based on the MS capabilities. This is part of WI "Technical Enhancements" and was approved at SMG#14. A.3 Proposed for WI "Technical enhancements" and required by WI "Multiband operation" A.3.1 AR 04.08-069 "Early Classmark Sending" and AR 04.08-071 "Early Classmark Sending" The multiband MS shall automatically send the CLASSMARK CHANGE message as soon as the main signalling link is established (Early Classmark Sending) if so permitted by the network, as indicated in the last reception in the accessed cell of the SYSTEM INFORMATION 3 message. A.3.2 AR 04.13-A002r1 "Performance requirements on the sending of the CLASSMARK CHANGE message" Requirements on the MS to send CM Change in the first uplink block after receiving UA-frame in downlink. A.3.3 AR 08.08-A013r3 "Early sending of CLASSMARK CHANGE" Inclusion of the option for the BSS to delay or suppress the sending of the CLASSMARK UPDATE message to the MSC in case the CLASSMARK CHANGE message was received at initial connection establishment. A.3.4 CR 09.90-033 "Early sending of Classmark change indication in CLASSMARK IE" A phase 2 MS uses one bit in Classmark 1 and 2 IE to indicate its capability in terms of early sending of classmark change message. This bit was associated to another meaning and its use leads to the use of a former reserved value. A.4 Proposed for WI "Multiband operation" A.4.1 AR 02.06-A001r2 "Definition of multiband MS type" Inclusion of multiband possibilities and definition of the multiband MS. A.4.2 AR 02.11-A004 "Clarifications for multiband operation" Clarifications about the possibilities to use multiband operation and presentation of available PLMNs. ETSI ETSI TR 101 266 V8.0.0 (2000-04) 12 (GSM 03.26 version 8.0.0 Release 1999) A.4.3 AR 03.22-A004 "Support of multiband operation by a single operator" Removal of inconsistencies with multiband operation. A.4.4 AR 04.08-A007r2 "Multiple band MSs in a dual band network" Extended coding of frequency and power capabilities in CM3. A.4.5 AR 04.08-A015r5 "New SI messages 2ter and 5 ter" Introduction of the two new SI messages 2ter and 5ter to ensure backwards compatibility. A.4.6 AR 05.01-A004 "Amendments for multiband operation" Clarification of the functionality of, and radio requirements on, multiband MSs. A.4.7 AR05.02-A001 "Inclusion of System Information 2ter for multiband operation" Scheduling of the sending of System Information 2ter on BCCH. A.4.8 AR 05.05-A008 "Amendments for multiband operation" Specification of possible frequency bands and the functionality of the multiband MS. A.4.9 AR 05.08-A006 "Amendments for multiband operation" Specification of the radio requirements, e.g. measurement reporting, on the multiband MS. A.4.10 AR08.58-A006r1 "Introduction of SI 2ter and 5ter" New code points for SI 2ter and 5ter included in GSM 08.58. ETSI ETSI TR 101 266 V8.0.0 (2000-04) 13 (GSM 03.26 version 8.0.0 Release 1999) A.4.11 CR11.10- 846 "Introduction of new section 26.11 for Multiband specific signalling tests" A.4.12 CR11.10- 847 "Inclusion of reference to new section 26.11 in introduction to section 26" A.4.13 CR11.10- 848 "Immediate assignment procedures: multiband" A.4.14 CR11.10- 849 "Handover procedure: Multiband MSs" A.4.15 CR11.10- 850 "Structured procedures, multiband" A.4.16 CR11.10- 851 "Default message contents for section 26.11" A.4.17 CR11.10- 852 "Modification of section 26.3 for Multiband MSs" A.4.18 CR11.10- 853 "Received signal measurements for multiband MSs" A.4.19 CR11.10- 854 "Measurement reporting for Multiband MS" A.5 Change Requests related to WI "Multiband operation" after 1996 NOTE: This may not be a complete list, and is provided for indicative purposes only. A.5.1 CR04.08-A178 "Handling of multiple frequency redefinitions" A179 was the matching CR for the phase 2 specification. A.5.2 CR04.08-A154r2 "Indication of multislot class" A.5.3 CR03.26- A002r1 "Amendment for multiband Operation (common BCCH for the different bands of operation)" A001r1 was the matching CR for the phase 2 specification. A.5.4 CR05.08-A035 "Amendment for multiband operation (common BCCH for the different bands of operation)” A034 was the matching CR for the phase 2 specification. Linked to CR03.26 A002r1 above. A.5.5 CR04.08-A214 "Coding of classmark information for multiband mobiles" A210r1 was the matching CR for the phase 2 specification. A.5.6 CR04.08-A207r1 "Handling of classmark information at band change" A204r2 was the matching CR for the phase 2 specification. ETSI ETSI TR 101 266 V8.0.0 (2000-04) 14 (GSM 03.26 version 8.0.0 Release 1999) A.5.7 CR 04.08-A239r2 “Clarification of use of L2 Pseudo Length in SYSTEM INFORMATION messages” (phase 2 , release -95) A.5.8 CR 04.08-A238r2 “Clarification of use of L2 Pseudo Length in SYSTEM INFORMATION messages“ (phase 2+, release -96) A.5.9 CR 09.94- A007r1 “Handling of new phase 2 BCCH and SACCH messages by phase 1 MS” ETSI ETSI TR 101 266 V8.0.0 (2000-04) 15 (GSM 03.26 version 8.0.0 Release 1999) Annex B (informative): Change History Change history SMG No. TDoc. No. CR. No. Section affected New version Subject/Comments SMG#23 4.3.0 Phase 2 version SMG#23 5.2.0 Phase 2+ version SMG#27 6.0.0 Release 1997 version SMG#29 7.0.0 Release 1998 version SMG#31 8.0.0 Release 1999 version ETSI ETSI TR 101 266 V8.0.0 (2000-04) 16 (GSM 03.26 version 8.0.0 Release 1999) History Document history V8.0.0 April 2000 Publication |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 1 Scope | The present document provides a description of the content of TIPHON Release 4 and shows the relevant documents and their inter-relationships. Each TIPHON release builds upon and extends the previous release. In this manner Release N contains and extends Release N-1, and is itself extended by Release N+1. The present document is structured as follows: • clause 4 introduces the release plan documentation set; • clause 5 defines the content and capabilities of TIPHON Release 4. The present document does not provide solutions for the technical issues that are identified therein. The present document is prepared in accordance with the TIPHON project method defined in TR 101 835 [1] and fulfils the requirements of Step A. In addition, the present document contains a comprehensive overview and description of the technical aspects of TIPHON Release 4. |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 2 References | For the purposes of this Technical Report (TR) the following references apply: [1] ETSI TR 101 835: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON); Project method definition". [2] ETSI EN 300 089: "Integrated Services Digital Network (ISDN); Calling Line Identification Presentation (CLIP) supplementary service; Service description". [3] ETSI EN 300 094: "Integrated Services Digital Network (ISDN); Connected Line Identification Presentation (COLP) supplementary service; Service description". [4] ETSI ETS 300 140: "Integrated Services Digital Network (ISDN); Call Hold (HOLD) supplementary service; Functional capabilities and information flows". [5] ETSI EN 300 357: "Integrated Services Digital Network (ISDN); Completion of Calls to Busy Subscriber (CCBS) supplementary service; Service description". [6] ETSI ETS 300 134: "Integrated Services Digital Network (ISDN); Signalling System No.7; Transaction Capabilities Application Part (TCAP)". [7] ETSI EN 301 133: "Integrated Services Digital Network (ISDN); Selective Call Forwarding (SCF) supplementary service (unconditional, busy and no reply); Service description". [8] ETSI EN 300 199: "Integrated Services Digital Network (ISDN); Call Forwarding Busy (CFB) supplementary service; Service description". [9] ETSI ETS 300 200: "Integrated Services Digital Network (ISDN); Call Forwarding Unconditional (CFU) supplementary service; Service description". [10] ETSI EN 300 201: "Integrated Services Digital Network (ISDN); Call Forwarding No Reply (CFNR) supplementary service; Service description". [11] ETSI ETS 300 202: "Integrated Services Digital Network (ISDN); Call Deflection (CD) supplementary service; Service description". [12] ETSI EN 301 082: "Integrated Services Digital Network (ISDN); Outgoing Call Barring-Fixed (OCB-F) supplementary service; Service description". ETSI ETSI TR 101 301 V3.1.1 (2004-04) 6 [13] ETSI EN 301 798 (V1.1.1): "Services and Protocols for Advanced Networks (SPAN); Anonymous Call Rejection (ACR) Supplementary Service; Service description". [14] ETSI ETS 300 056: "Integrated Services Digital Network (ISDN); Call Waiting (CW) supplementary service; Service Description". [15] ETSI ETS 300 186: "Integrated Services Digital Network (ISDN); Three-Party (3PTY) supplementary service; Service description". [16] ETSI ETS 300 178: "Integrated Services Digital Network (ISDN); Advice of Charge: charging information at call set-up time (AOC-S) supplementary service; Service description". [17] ETSI ETS 300 179: "Integrated Services Digital Network (ISDN); Advice of Charge: charging information during the call (AOC-D) supplementary service; Service description". [18] ETSI ETS 300 180: "Integrated Services Digital Network (ISDN); Advice of Charge: charging information at the end of the call (AOC-E) supplementary service; Service description". [19] ETSI TS 101 331: "Telecommunications security; Lawful Interception (LI); Requirements of Law Enforcement Agencies". [20] ETSI TR 101 750: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON); Requirements Definition Study; Studies into the Impact of lawful interception". [21] ETSI EN 300 924 (Edition 3): "Digital cellular telecommunications system (Phase 2+) (GSM); enhanced Multi-Level Precedence and Pre-emption Service (eMLPP) - Stage 1". [22] ETSI TR 101 300: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON); Description of Technical Issues". [23] IETF RFC 2543: "SIP: Session Initiation Protocol". [24] ETSI TS 101 882: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 3; Protocol Framework Definition; General (meta-protocol)". [25] ETSI TS 101 314: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Abstract Architecture and Reference Points Definition; Network Architecture and Reference Points". [26] ETSI TR 102 008: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 3; Terms and Definitions". [27] ITU-T Recommendation H.323: "Packet-based multimedia communications systems". [28] ITU-T Recommendation E.164: "The international public telecommunication numbering plan". [29] ETSI TR 101 326: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON); The procedure for determining IP addresses for routeing packets on interconnected IP networks that support public telephony". [30] ETSI TR 101 858: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON); Number portability and its implications for TIPHON networks". [31] ETSI TR 101 329-1: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 3; End-to-end Quality of Service in TIPHON systems; Part 1: General aspects of Quality of Service (QoS)". [32] ITU-T Recommendation E.600: "Terms and definitions of traffic engineering". [33] ITU-T Recommendation G.107: "The E-Model, a computational model for use in transmission planning". [34] ITU-T Recommendation P.310: "Transmission characteristics for telephone band (300 - 3 400 Hz) digital telephones". ETSI ETSI TR 101 301 V3.1.1 (2004-04) 7 [35] ETSI TS 101 329-5: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 3; End-to-end Quality of Service in TIPHON systems; Part 5: Quality of Service (QoS) measurement methodologies". [36] ETSI TS 101 329-2: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 3; End-to-end Quality of Service in TIPHON systems; Part 2: Definition of speech Quality of Service (QoS) classes". [37] ETSI TR 101 329-7: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 3; End-to-end Quality of Service in TIPHON systems; Part 7: Design guide for elements of a TIPHON connection from an end-to-end speech transmission performance point of view". [38] ETSI TS 101 329-3: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 3; End-to-end Quality of Service in TIPHON systems; Part 3: Signalling and control of end-to-end Quality of Service (QoS)". [39] IETF RFC 2401: "Security Architecture for the Internet Protocol". [40] IETF RFC 2246: "The TLS Protocol Version 1.0". [41] ITU-T Recommendation H.235: "Security and encryption for H-Series (H.323 and other H.245-based) multimedia terminals". [42] ETSI TR 101 877: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON); Requirements Definition Study; Scope and Requirements for a Simple call". [43] ETSI TR 101 311: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 3; Service Independent requirements definition; Transport Plane". [44] ETSI TS 101 878: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Service Capability Definition; Service Capabilities for TIPHON Release 4". [45] ETSI TS 101 315: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Information flow and reference point definitions; Implementation of service capabilities". [46] ETSI ETR 298: "Methods for Testing and Specification (MTS); Specification of protocols and services; Handbook for SDL, ASN.1 and MSC development". [47] ITU-T Recommendation Q.931: "ISDN user-network interface layer 3 specification for basic call control". [48] ITU-T Recommendation H.225.0: "Media stream packetization and synchronization on non-guaranteed quality of service LANs". [49] ITU-T Recommendation H.245: "Control protocol for multimedia communication". [50] ITU-T Recommendation H.248: "Gateway control protocol". [51] IETF RFC 2327: "SDP: Session Description Protocol". [52] IETF RFC 3015: "Megaco Protocol Version 1.0". [53] ETSI TS 101 883: "Telecommunications and Internet protocol Harmonization Over Networks (TIPHON) Release 4; Technology Mapping; Implementation of TIPHON architecture using H.323". [54] ETSI TS 101 884: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 3; Technology Mapping; Implementation of TIPHON architecture using SIP". [55] ETSI TS 101 885: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Interface Protocol Requirements Definition; Implementation of TIPHON using H.248/MEGACO". ETSI ETSI TR 101 301 V3.1.1 (2004-04) 8 [56] Void. [57] ETSI TS 101 520: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON); Implementation Conformance Statement (ICS) proforma for the support of packet based multimedia communications systems; Support of ITU-T Recommendation H.323". [58] ETSI TS 101 521: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON); Protocol Implementation Conformance Statement (PICS) proforma for the support of call signalling protocols and media stream packetization for packet-based multimedia communication systems; Support of ITU-T Recommendation H.225.0". [59] ETSI TS 101 522: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON); Protocol Implementation Conformance Statement (PICS) proforma for the support of control protocol for multimedia communication; Support of ITU-T Recommendation H.245". [60] ETSI EG 201 058: "Methods for Testing and Specification (MTS); Implementation Conformance Statement (ICS) proforma style guide". [61] ETSI ETR 266: "Methods for Testing and Specification (MTS); Test Purpose style guide". [62] ETSI EG 202 103: "Methods for Testing and Specification (MTS); Guide for the use of the second edition of TTCN". [63] ETSI ETR 141: "Methods for Testing and Specification (MTS); Protocol and profile conformance testing specifications; The Tree and Tabular Combined Notation (TTCN) style guide". |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 3 Abbreviations | For the purposes of the present document, the following abbreviations apply: API Application Programming Interface ASN1 Abstract Syntax Notation One ATS Abstract Test Suite ATS Abstract Test Suite BC Bearer Control BICC Bearer Independent Call Control CC Call Control CCBS Completion of Call to BusySubscriber CCNR Completion of Call on NoReply CLI Calling Line Identification CLIP Calling Line Identification Presentation CLIR Calling Line Identification Restriction CUG Closed User Group DSS1 Digital Subscriber Signalling One ETS Executable Test Suite GSM Global System for Mobile communications ICANN Internet Corporation for Assigned Names and Numbers ICLID Incoming Call LineID ICS Implementation Conformance Statement IN Intelligence Network INAP Intelligent Natwork Application Part IP Internet Protocol ISDN Integrated Services Digital Network ISUP Integrated Switched Digital Network User Part ITSP IP Telephony Service Provider IXIT Implementation eXtra Information for Testing LI Lawful Interception MC Media Control MSC Message Sequence Charts OSP Open SettlementProtocol PICS Protocol Implementation Conformance Statement ETSI ETSI TR 101 301 V3.1.1 (2004-04) 9 PSTN Public Switched Telephone Network PT Packet Telephony QoS Quality of Service RTP Real-time TransportProtocol SAP Service Access Point SC Service Control SCN Switched Circuit Network SDL Specification and Description Language SDP Service DatatPoint SE Services SIP Session Initiation Protocol TCC TIPHON Call Control TCC-SAP TIPHON Call Control Service Access Point TLL TIPHON Lower Layer TLL-SAP TIPHON Lower Layer Service Access Point TLS Transport Layer Security TNO Transport Network Operator TR TIPHON Registration TR-SAP TIPHON Registration Service Access Point TSS&TP Test Suite Structure and Test Purposes TT TIPHON Transport TT-SAP TIPHON Transport Service Access Point UML Unified ModellingLanguage VoIP Voice over IP |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 4 An overview of the TIPHON approach | Release 3 was the first major edition of TIPHON documentation to be made publicly available and, as such, represents a considerable amount of effort from the members of the TIPHON Project. Release 4 adds several new service capabilities to enable a feature-rich portfolio of services to be constructed using the TIPHON specifications. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 10 Several additional telephony-related requirements for support in TIPHON Release 4 have been identified and include: Support for Enhanced Residential Service Calling Number /Name Presentation (CLI / ICLID etc.) [2] Connected Line Presentation/Restriction [3] Message waiting Message Indication Call Return Call Hold [4] Transfer Ring-Back (Auto Callback, CCBS, CCNR) [5]; [6] Call Forward (UC/C/B/DA/V/NR, Deflect) [7], [8], [9], [10] and [11] Call Barring (Outgoing) (Soft Dial-Tone) [12] Call Barring (Incoming) ACI, ACR, Selective, etc. [13] Call Barring (Incoming) Bypass Alarm/Reminder Call Distinctive Alert (Call Sign) Call Waiting Indication [14] Terminal Portability 3-way Conference (n-way) [15] Call Trace (Malicious Call ID) Advice of duration and charge [16], [17] and [18] Multiple subscriber numbers Network Redial FAX In-band Data Transport (Modem pass-through) Support for SME: Basic Business Service Features in High-end residential Plus: Account Codes Call Park Call Pick-up (Group/Directed) Short Code (Dialling Plans) Hunt Groups Closed User Group (CUG) Service Provider Operational Capabilities Line Service (General) Interrogation Call Trace Barge-In (n/a) Howler The following are deferred to a subsequent TIPHON release: • APIs; • Multi-media; • Instant messaging. These Key requirements include naming and numbering policies, Quality of Service, Lawful Interception [19] and [20] emergency and priority calls [21] and security. |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 4.1 Basic TIPHON Scenarios | In order to establish the requirements for service creation, architecture, signalling and service support in a TIPHON environment, it is necessary to consider four basic scenarios [22] from which all other (more complex) scenarios can be derived. These basic scenarios are: • Scenario 1: simple call from a user in a Voice over IP (VoIP) network to another user in an adjacent Switched Circuit Network (SCN) such as ISDN. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 11 • Scenario 2: simple call from a user in a SCN, to another user in an adjacent VoIP network using SIP or a similar protocol. • Scenario 3: call from a user in a SCN to a user in another SCN where the call is routed through one or more transit networks of which at least one is a VoIP network. • Scenario 0: call from a user in a VoIP network is routed to another user in a different VoIP network. In each of these scenarios (see figures 1 to 4), the interface between the disparate networks is identified as a "TIPHON Gateway". In real-world implementations this may or may not be a separate item of physical equipment but it is the interoperation of both protocol and media at this point that is a focus of TIPHON standardization. The other focus of TIPHON is the behaviour within the domains (especially those on IP technology) where the current state of the art is not mature enough that it allows proper interworking with the SCN. |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 4.1.1 Scenario 1: VoIP call to SCN user | VoIP Network VoIP Network TIPHON Gateway Call Setup SCN SCN Signalling Path Media Path Figure 1: TIPHON Scenario 1 A call arrives at a TIPHON Gateway from a VoIP user and the destination is in an adjacent SCN. Signalling takes place between the VoIP network and the Gateway where the Gateway acts on behalf of the SCN user. |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 4.1.2 Scenario 2: SCN call to VoIP user | SCN SCN VoIP Network VoIP Network TIPHON Gateway Call Setup Signalling Path Media Path Figure 2: TIPHON Scenario 2 A call arrives at a TIPHON Gateway from a user in a SCN and the destination is in an adjacent VoIP network. Signalling takes place between the Gateway and the VoIP network with the Gateway acting on behalf of the calling user. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 12 |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 4.1.3 Scenario 3: SCN call to SCN user via a VoIP network | TIPHON Gateway Call Setup TIPHON Gateway SCN SCN VoIP Network VoIP Network SCN SCN Signalling Path Media Path Figure 3: TIPHON Scenario 3 A call from one SCN user to another SCN user passes through at least one VoIP network, transiting a TIPHON gateway at each network interworking boundary. The gateways act on behalf of the SCN users in their negotiations with the VoIP network(s). This scenario is essentially a combination of Scenarios 1 and 2. |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 4.1.4 Scenario 0: VoIP call to VoIP user | This scenario is shown in figure 4 and is referred to as TIPHON Scenario 0. TIPHON Gateway Call Setup VoIP Network VoIP Network VoIP Network VoIP Network Signalling Path Media Path Figure 4: TIPHON Scenario 0 ETSI ETSI TR 101 301 V3.1.1 (2004-04) 13 |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 4.2 The TIPHON "Tool Box" | In order to achieve interworking between existing SCN technologies (for example, DSS1) and IP media technologies (for example, SIP [23]) as well as possible future technologies, TIPHON has specified a meta-protocol which provides communication between the two sides of a TIPHON Gateway. Although it is unlikely, and unnecessary, that any TIPHON-compliant equipment will implement the meta-protocol, a protocol that has been mapped to the meta-protocol should also interwork with any other protocol that is also mapped to the meta-protocol. It is these mappings and the profile standards (closing options and identifying limitations) that are the key outputs of the overall TIPHON process. This process, as shown in figure 5, can be viewed as a tool box taking a set of fixed TIPHON requirements and a range of technology-specific inputs to produce mapping and profile standards with their associated test suites. TIPHON Tool Box Requirements Protocol Architecture Numbering Security QoS Services Mapping and Profiles Profile Test Suites Technology Standards Figure 5: The TIPHON "Tool Box" Although some mapping and profile standards are included in the TIPHON project deliverables, the meta-protocol is published as an open standard so that any standardization body may prepare TIPHON mapping and profile standards for any communication protocol that they have responsibility for. |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 4.3 A simple TIPHON reference model | |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 4.3.1 TIPHON network element | A review of the scenarios shown in figure 1 to 4 is helpful in determining the basic modelling aspects which are required for the development of the TIPHON protocol framework [24]. In generic terms, each network involved in a TIPHON environment can be considered, with its TIPHON Gateway(s), to be a "black-box" as shown in figure 6. TIPHON Gateway Network Network TIPHON Gateway Signalling Path Media Path Figure 6: TIPHON network element ETSI ETSI TR 101 301 V3.1.1 (2004-04) 14 A special case of this black-box is a network connected to a TIPHON gateway on one side but to a user on the other, as shown in figure 7. Network Network TIPHON Gateway User Signalling Path Media Path Figure 7: TIPHON network element with Gateway and user The TIPHON network element shown in figure 7 is further refined into 2 elements representing the calling user's network and the called user's network, as shown in figure 8. Network Network TIPHON Gateway Called User Network Network TIPHON Gateway Calling User Signalling Path Media Path Figure 8: Origination and destination TIPHON network elements |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 4.3.2 Reference model | Any of the scenarios in figure 1 to 4 can now be constructed using the three TIPHON network elements shown in figures 6 and 8. These elements can also be used as the basis for a TIPHON reference model. This is shown in simple form in figure 9. Originating TIPHON Network Transit TIPHON Network Destination TIPHON Network TIPHON Gateway Gateway Reference Point Gateway Reference Point Gateway Reference Point Gateway Reference Point TIPHON Gateway Figure 9: Simple TIPHON reference model Communication at the gateway reference point is implemented using the TIPHON meta-protocol (see clause 4.2) with which the network protocols (originating, transit and destination) interwork. TS 101 314 [25] specifies a more detailed reference model and reference configuration for TIPHON systems. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 15 |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 5 Release 4 | The main focus of the TIPHON Release 4 project has been to ensure that all technical issues related to Voice over IP (VoIP) - particularly with respect to Scenario 0 - were considered and fully analysed. The published Release 4 documents reflect this goal. The remainder of clause 5 in the present document identifies each of the documents published as part of TIPHON Release 4. |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 5.1 Document type definitions | TIPHON documents produced for Releases 4 fall within the categories defined in table 1. Table 1: Document type categorization and definitions Step Document Category ETSI document type RDS Requirements definition study Technical Report A Release definition Technical Specification Design guide Technical Report B Service independent requirements definition Technical Report Service capability definition Technical Specification C Abstract architecture and reference ponts definition Technical Specification Information flow definitions Technical Specification D Management framework definition Technical Specification Protocol framework definition Technical Specification Interface protocol requirements definition Technical Specification E Technology compliance specification Technical Specification Technology mapping Technical Specification |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 5.2 Definition of terms | To ensure that the definition of terms used for TIPHON Release 4 documents are used in a consistent way, TR 102 008 [26] contains an agreed set of definition of terms used in Release 3. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 16 |
c7e3f9aa2d9e3c83e32ba96688c3314b | 101 301 | 5.3 TIPHON Release 4 Work Items | The following issues have been identified as forming the essential elements of TIPHON Release 4. Table 2: Topics and issues covered in Release 4 WG Topic 1 Service capabilities to support simple call 1 Service independent requirements for service and network management 1 Service independent requirements for the transport plane 2 Amendments of architecture to include lawful interception, security and usage information 2 Extension for inter domain services 3 Profiling of key protocols (SIP, H.323, H.248) 3 Protocol independent framework 4 Choice of identification/contact address 4 Address resolution service 5 QoS classification 5 QoS functions and primitives 5 QoS control 5 QoS measurement 5 QoS design guidelines 6 Complete set of test specs for H.225.0 6 PICS for H.245 and H.248 6 Interoperability test specification 8 Lawful interception 8 Security profiles The remainder of this clause identifies those TIPHON work items that support these issues. Table 3: TIPHON work items forming Release 4 TIPHON Work Item ETSI Number Step Title RTS/TIPHON-01004R4 101 303 A Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Service Independent Requirements Definition; Service and Network Management Framework; Overview and Introduction RTR/TIPHON-00002R4 101 301 A Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Release Definition; TIPHON Release 4 Definition RTS/TIPHON-01009R4 101 878 B Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Service Capability Definition; Service Capabilities for TIPHON Release 4 RTS/TIPHON-02007R4 101 315 C Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Information flow and reference point definitions; Implementation of service capabilities RTS/TIPHON-02009R4 101 314 C Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Abstract Architecture and Reference Points Definition; Network Architecture and Reference Points RTS/TIPHON-03004R4 101 321 D Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Open Settlement Protocol (OSP) for Inter-Domain pricing, authorization and usage exchange RTS/TIPHON-03016-1R4 101 882-1 D Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Protocol Framework Definition ; Part 1: Meta-protocol design rules, development method, and mapping guideline ETSI ETSI TR 101 301 V3.1.1 (2004-04) 17 TIPHON Work Item ETSI Number Step Title RTS/TIPHON-03016-2R4 101 882-2 D Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Protocol Framework Definition; Part 2: Registration and Service Attachment service meta-protocol definition RTS/TIPHON-03016-3R4 101 882-3 D Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Protocol Framework Definition; Part 3: TIPHON Simple Call service meta-protocol definition RTS/TIPHON-03016-4R4 101 882-4 D Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Protocol Framework Definition; Part 4: Media Control Service meta-protocol definition DTS/TIPHON-03016-5R4 101 882-5 D Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Protocol Framework Definition; Part 5: Transport control service RTS/TIPHON-03017R4 101 883 E Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Technology Mapping; Implementation of TIPHON architecture using H.323 RTS/TIPHON-03018-1R4 101 884-1 E Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Technology Mapping; Part 1: Implementation of TIPHON architecture using SIP RTS/TIPHON-03019R4 101 885 E Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Interface Protocol Requirements Definition; Implementation of TIPHON using H.248/MEGACO DTS/TIPHON-03021R4 102 228 E Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Technology Mapping Implementation of TIPHON architecture using BICC DTS/TIPHON-03022R4 102 229 E Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Interface Protocol Requirements Definition; Aggregate Bearer Load Control - H.248 Package DTS/TIPHON-03027R4 101 332 E Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Interface Protocol Requirements Definition; TIPHON Extended H.248/MEGACO Package (EMP) Specification; ICF Control over Reference Point DTS/TIPHON-03028R4 102 108 E Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; H.248/MEGACO Profile for TIPHON reference point I3; InterConnect Function (ICF) control over reference point I3 RTS/TIPHON-06014R4 101 888 E Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Test Scenarios; Security testing - H.323 environment DTS/TIPHON-06014-2R4 101 888-2 E Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Security Test Specifications; Part 2: H.323 Environment DTS/TIPHON-06025-1R4 102 237-1 E Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Interoperability test methods and approaches; Part 1: Generic approach to interoperability testing ETSI ETSI TR 101 301 V3.1.1 (2004-04) 18 TIPHON Work Item ETSI Number Step Title QoS Work Items DTR/TIPHON-05007R4 102 024-1 WG 5 Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; End-to-End Quality of Service in TIPHON Systems; Part 1: General aspects of Quality of Service (QoS) DTS/TIPHON-05012R4 102 024-2 WG 5 Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; End-to-end Quality of Service in TIPHON Systems; Part 2: Definition of Speech Quality of Service (QoS) Classes DTS/TIPHON-05003R4 102 024-3 WG 5 Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; End-to-End Quality of Service in TIPHON Systems; Part 3: Signalling and Control of end-to-end Quality of Service (QoS) ikn a multi-media environment DTS/TIPHON-05010R4 102 024-4 WG 5 Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; End-to-End Quality of Service in TIPHON Systems; Part 4: Quality of Service Management DTS/TIPHON-05008R4 102 024-5 WG 5 Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; End-to-end Quality of Service in TIPHON Systems; Part 5: Quality of Service (QoS) measurement methodologies DTR/TIPHON-05013R4 102 024-6 WG 5 Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; End-to-End Quality of Service in TIPHON Systems; Part 6: Actual measurements of network and terminal characteristics and performance parameters in TIPHON networks and their influence on voice quality DTR/TIPHON-05014R4 102 024-7 WG 5 Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; End-to-End Quality of Service in TIPHON Systems; Part 7: Design Guide for elements of a TIPHON connection from an end-to-end speech transmission performance point of view DTR/TIPHON-05016R4 102 024-9 WG 5 Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; End-to-End Quality of Service in TIPHON Systems; Part 9: Call performance Classification (Voice) DTSR/TIPHON-05020R4 102 024-12 WG 5 Telecommunications and Internet protocol Harmonization Over Networks (TIPHON) Release 4; End to End Quality of Service in TIPHON Systems; Part 12: IP Telephony Service Availability WG 8 "Security" DTS/TIPHON-08005-1R4 102 165-1 WG 8 Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Protocol Framework Definition; Methods and Protocols for Security; Part 1: Threat Analysis DTS/TIPHON-08005-2R4 102 165-2 WG 8 Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Protocol Framework Definition; Methods and Protocols for Security; Part 2: Counter Measures DTR/TIPHON-08002R4 101 771 WG8 Telecommunications and Internet protocol Harmonization Over Networks (TIPHON) Release 4; Service Independent requirements definition; Threat Analysis ETSI ETSI TR 101 301 V3.1.1 (2004-04) 19 TS 101 878 Service Capability Simple Call Service & Nwk Mgmt Framework TS 101 303 Release 4 Ref Architecture TS 101 314 Inter-Domain "Implementor's Guide" TS 101 315 Implementation of TIPHON using SIP TS 101 884 Implementation of TIPHON using H.248 TS 101 885 Implementation of TIPHON using H.323 TS 101 883 Meta Protocol Definition TS 101 882 -1 to -5 OSP TS 101 321 Lawful Interception TS 102 227 Implementation of TIPHON using BICC TS 102 228 Aggr Bearer Load Control - H.248 pkg TS 102 229 6010-1 to -3R4 work in progress OSP test suites acc to TIPHON profile 06020-1 to -3 work in progress SIP test suites acc to TIPHON profile 6023-1 to -3R4 work in progress BICC test suites acc to TIPHON profile 6024-1 to -3R4 work in progress Extended H.248/MEGACO Pkg - test suites 6025-1 to -3R4 work in progress Interoperability test methods, scenarios, testbed TIPHON Release 4 definition TR 101 301 QoS Signalling TS 102 024-3 Security testing - H.323 environment TS 102 165 parts 1 and 2 Threat Analysis and Counter Measures TS 101 888 parts 1 and 2 Figure 10: Documents contained in Release 3 (Step A not shown) ETSI ETSI TR 101 301 V3.1.1 (2004-04) 20 Annex A: TIPHON Release 4 Annex A presents an overview of the TIPHON process from the perspective of TIPHON Release 4 specifications. A.1 Background The telecommunications industry is promoting the migration from Switched Circuit Networks (SCN) to multi-service packet networks. This migration will provide benefits in terms of economics and new services. One of the greatest challenges in this migration is creating a packet-based infrastructure that will preserve the ubiquity, quality, and reliability of voice services while allowing the greatest flexibility for use of the new packet technologies. In the present document, an architecture is presented that can serve in both the migration path to that infrastructure and in all packet solutions. The aim of the Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) project is to address service level interworking between traditional Switched Circuit Networks (SCNs) and the emerging next generation networks based on VoIP technology. This objective supports the market for real-time telecommunication services between users, including voice and related voice-band communication, such as facsimile, over multiple network technologies. Until recently, Packet Telephony (PT) technology was too immature to replace traditional telephony networks. Early work on Packet telephony was focused on developing boxes and protocols to solve particular small-scale problems such as long distance bypass. To be considered mature enough, the packet network must be able to adhere to commercial and legal requirements. This implies that a PT deployment should be able to provide guarantees for the availability and quality of the service, should be able to interwork with other packet telephony domains that may be governed by other policies, and should allow billing for used services. TIPHON Release 4 should enable users connected to IP-based networks to communicate between themselves and also with users in SCNs especially those served by PSTN, ISDN or GSM networks. TIPHON has considered a diverse set of requirements including security, quality of service and numbering. In this TIPHON Release, the issue of providing telephony services in a heterogeneous environment is addressed. A generic method for service creation has been developed that is independent of any specific underlying network technology e.g. switched circuit or packet based. TIPHON has identified an overarching technology and a generic meta-protocol i.e. a domain-independent protocol framework. The architecture described in the present document fully supports the fact that most calls traverse multiple provider networks, which may use different transport technologies or call/service signalling protocols. To achieve these goals a transport-independent, functional model for provider domains is created. This allows the solution to address, for instance, introduction of new services separately from interworking between different transport technologies. A model is proposed that groups transport-related functions and application-related functions in separate planes. The planes are further divided into layers. The elements in these layers may be re-used as the building blocks for future generations of similar services. The meta-protocols are used to generate profiles for the protocols associated with any given communications network technology. By mapping this "meta-protocol" to individual network technologies, TIPHON has ensured an effective path to an end-to-end network capability. This approach leads to a packet telephony architecture that can be used to offer services on par with those offered on legacy telephone networks and that can provide an evolution path to broadband and mobile applications. However, multi-media conferencing, instant messaging and e-commerce are applications and services that go beyond the common services provided by today's PSTN or basic Internet connectivity and will be addressed in a later release of TIPHON. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 21 A.1.1 TIPHON Releases 1 and 2 TIPHON Release 1 addressed a discrete set of scenarios comprising calls from: • an IP device to a phone (Scenario 1); • a phone to an IP device (Scenario 2); • a phone to another phone via an IP network (Scenario 3); • an IP device to another IP device via a Switched Circuit Network (Scenario 4). These Release 1 scenarios were grouped into "Phases" of activity; Phase 1 related to Scenario 1 and so on. It rapidly became clear that a simple model was insufficient to achieve the projects aims since it left little opportunity for equipment manufacturers and service providers to create scaleable, multi-vendor, multi-service provider, network implementations. Release 2 attempted to address the development of a more functionally orientated architecture elaborating on gateway devices required to interconnect IP based terminals with switched circuit networks. The scenario models considered within both of these releases failed to reflect the reality of IP networks being constructed from a concatenation of individual discrete physical networks. Consequently, a more versatile approach to the development of standards needed for viable VoIP was devised for Release 3. A.1.2 TIPHON Release 3 TIPHON Release 3 addresses simple call with minimal service features beyond those provided by basic call. The TIPHON process has been validated through the publication of the complete set of deliverables forming Release 3. This process is described in the following clauses. A.2 The TIPHON Release 4 process The TIPHON project has considered a wide range of complex technology issues arising from the interworking of differing and independently evolving network technologies. For example, these technologies include, but are not limited to IP, PSTN, H.323 [27] and SIP [23]. The TIPHON process therefore comprised two distinct stages. The first stage was concerned with establishing a fixed set of requirements to define the scope of TIPHON Release 4. The second stage was concerned with developing a coherent set of technical specifications from the fixed set of requirements for TIPHON Release 4, as shown in figure A.1. Requirements definition studies TIPHON release scheduling Scope of TIPHON TIPHON scenarios Market requirements Step B Step C Step D Step E Step A Step B Step C Step D Step E Step A Step B Step C Step D Step E Step A Step B Step C Step D Step E Step A Release n Figure A.1: Overview of the TIPHON process ETSI ETSI TR 101 301 V3.1.1 (2004-04) 22 As part of this TIPHON process, five main types of document were developed: • Service application descriptions: where only simple call is specified. These are equivalent to rather more general forms of Stage 1 service descriptions. TIPHON is not intending to define service applications so that service providers may choose to design and implement their own applications. However TIPHON has defined the simple call service application partly to test out/demonstrate the way in which service capabilities can be used and partly because of the significance of simple calls in circuit switched networks. • Standardized service capabilities: The standardized technical capabilities that can be used to implement service applications (market parties may define additional non-standardized service capabilities to differentiate their service applications from those of competitors). • A functional architecture: a list and classification of functions providing a framework in which to embed the service capabilities. • A meta-protocol: a protocol describing messages to be sent, their information content and the behaviour of systems when the messages are to be sent or when they are received. This meta-protocol is not designed for direct implementation but is specified to provide a common reference point for other protocols so that for N different real protocols the protocol mapping task is reduced from N*(N-1) mappings between the real protocols to N mappings to the meta-protocol. The description of the meta-protocol is related to the service capabilities. • Protocol mappings: from the meta-protocol to real protocols to implement the service capabilities. Those considered at present include the various flavours of SIP, H.323, BICC, ISUP and H.248. A.3 Release definition (Step A) As shown in figure A.2, TIPHON Release 4 was constructed from a set of qualified requirements that were progressed through to a coherent and focussed set of specifications of the necessary quality within an acceptable period of time. The Release 4 definition comprises of a statement of the top-level topics that were addressed together with a plan which identifies the associated deliverables. TIPHON Scope, Scenarios, Market Requirements and Requirements Definition Studies Step B Step B TIPHON Release Definition for Release n TIPHON Release n Plan Other Steps Figure A.2: Step A - Release definition in TIPHON Requirements definition studies provided a flexible route to TIPHON Release 4 ensuring adaptation of its work to meet the continuing changes in the market place. These studies were initiated within the TIPHON working groups to explore aspects requiring further study, and were timed to deliver requirements into the TIPHON Release 4. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 23 In TIPHON systems, users are free to attach terminals to any consenting access network administrative domain. The consenting IP Telephony Service Provider (ITSP) responsible for the access network administrative domain has a contract, either directly or indirectly, with another IP Telephony Service Provider with whom the user has a contract. These contracts provide a relationship between the user and both IP Telephony Service Providers for the purpose of providing a service application (like simple call) to the terminal's user. A.3.1 Simple call requirements Several telephony-related requirements have been addressed in TIPHON Release 4. These requirements have been identified for the support of simple call i.e. voice calls which are on a par with the PSTN and include: • emergency calls; • CLIP/CLIR; • number portability; • QoS for the calls; • privacy; • Lawful Interception (LI); • authentication of users; • billing; • user mobility (roaming); • carrier (pre)selection; • call forwarding services. However, the following are deferred to a subsequent TIPHON release: • APIs; • management; • 3 party calls; • conferencing; • multi-media; • instant messaging. Key requirements include naming and numbering policies, Quality of Service and security and their support by the network and are discussed in the following clauses. A.3.1.1 Naming The choice of the naming scheme to be used is an important part of the specification of a service because the choice of naming scheme places an absolute limit on the set of entities that can be communicated with. Also, any network that provides the service or provides service level interconnection needs to be able to resolve the names used into addresses using information obtained from registration. For roaming level interconnection, this does not apply. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 24 Call set-up and some other service capabilities involve names. For call set-up at least, these names have to be resolved into addresses for routing. This can occur in several stages by networks with service level interconnection but is performed finally by the home network. All these networks need to be able to understand the naming scheme used (for this user). The final resolution needs to use information obtained during the registration process of the terminating user. A home network will have this information for its own customers as a result of registration, but will not have this information for users normally registered with an interconnected network. In order to set up calls to customers of an interconnected network service level interconnection is needed. This must ensure that customers can be identified by names, allowing the interconnected network to use its own registration information for resolving these names to addresses. In contrast, roaming level interconnection only extends the reach of registration and thus the home service provider can still resolve the names of its customers to addresses on the visited networks. Thus roaming level interconnection does not require the support of the same naming scheme and only requires knowledge of addresses. Naming schemes are not specified in the definition of the service capabilities, thus where service capabilities involve naming they can be used with any naming scheme, although the choice if naming scheme is an essential part of the service application. Some service capabilities, however, (e.g. number portability) apply only to the support of specific naming schemes (e.g. ITU-T Recommendation E.164 [28]). The three naming schemes available to be considered at present are: • public telephony numbers E.164 defined by ITU; • internet names defined by ICANN; • unspecified private naming schemes. TIPHON has produced TR 101 326 [29], which explains how name to address resolution is to be handled for E.164. TIPHON has also produced TR 101 858 [30] which gives more information on Number Portability and its implication for TIPHON networks. The support of E.164 is essential for the support of public telephony and for interworking with the PSTN/ISDN/GSM in TIPHON Release 4. Work on the support of Internet naming is planned for a later TIPHON release. A.3.1.2 Quality of Service Quality of Service (QoS) is a hot topic in IP transport discussions. It is generally understood that many applications are hampered, if not made impossible, by the lack of QoS in many of today's best effort IP networks. It is necessary to have enough bandwidth available for the application, but bandwidth alone is not sufficient. Other parameters that are critical to applications that involve real-time media streams are delay, jitter, and packet loss. The ability of today's networks to deliver the desired values for these parameters depends critically on the network load; no guarantees can be provided for the QoS delivered. Although several QoS mechanisms have been standardized in the IETF none have yet seen wide deployment. It is believed that transport QoS will only be deployed if the investments allow the generation of revenue, implying that a QoS-capable network will only give its service to paying customers. A QoS transport network will therefore have some means of access control (which includes end-user authentication) to protect the network from unauthorized usage and overloading. In TIPHON documents we place end-user authentication in the application plane and we define an interface between the transport and application planes that allows the entities in the application plane to request an end-to-end bit pipe through the transport network. End-to-end QoS in a TIPHON system is characterized in the TIPHON QoS documentation TR 101 329-1 [31] under two broad headings: • call set-up quality; and • call quality. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 25 Call set-up quality is mainly characterized by the call set-up time which is perceived by the user as the responsiveness of the service. Call set-up time is the time elapsed from the end of the user interface command by the caller (keypad dialling, E-mail alias typing, etc.) to the receipt by the caller of meaningful progress information. TIPHON QoS documents provide the exact definition of the various call set-up times for use in TIPHON systems, whereas ITU-T Recommendation E.600 [32] provides more information on the definition of post-dialling delay in SCN systems. Call quality is characterized by the overall transmission quality rating R which describes the full acoustic-to-acoustic (mouth to ear) quality, experienced by a user, for a typical situation using a "standard" telephony handset. The overall transmission quality rating is calculated using the E-Model described in ITU-T Recommendation G.107 [33]. For calculation purposes the use of traditional telephone handsets at both sides of the connection is assumed as described in ITU-T Recommendation P.310 [34]. Within the overall transmission quality two major factors contribute to the overall QoS experience of the user of the TIPHON system: • end-to-end delay: this mainly impacts the interactivity of a conversation. The measurement is done from the mouth of the speaker to the ear of the listener; and • end-to-end speech quality: this is the one-way speech quality as perceived in a non-interactive situation. The measurement methodologies for these parameters are specified in TS 101 329-5 [35], while the requirements for these parameters with respect to the various TIPHON QoS classes are defined in TS 101 329-2 [36]. TR 101 329-7 [37] provides guidance on these parameters with respect to the practical design phase of equipment and networks and TS 101 329-3 [38] describes the signalling and control of end-to-end Quality of Service in TIPHON Systems. A.3.1.3 Security Transport security is a relatively new concept in telecommunications networks. Like QoS it was taken for granted in the traditional SCN. End-to-end one would like to achieve a private, uninterrupted and authenticated communication. By assuming that the lines of communication in the PSTN cannot be tapped one can assume that the phone network provided this. The Internet was designed for end-to-end transparency implying that the network behaviour is independent of distance and that addresses are globally routable and independent of location. The whole world looks like a big local area network to a terminal on the Internet. This model works well for a generic packet service since the network itself only transports packets and does not get involved in the content. This transparency has benefited the growth of the Internet allowing the rapid deployment of new services. On packet networks one does not make these assumptions because in the most common form of packet network (IP over Ethernet), everyone broadcasts their messages assuming the intended recipient will see it. Several techniques have been devised to achieve the goal of private and authenticated communication. Communication can be signed and encrypted in several ways: at the IP level IPsec can be used [39], on the transport level Transport Layer Security (TLS) can be used [40] and in the application. See ITU-T Recommendation H.235 [41] for an overview of security methods. Public peer-to-peer communications is an open invitation for hackers to try and disable servers and users terminals. Consequently, users who access to the internet can expect to be monitored from well beyond their immediate network connection. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 26 A.4 Capabilities and requirements (Step B) Step B developed appropriate service capability definitions and associated statements of service independent Requirements using the information contained and referenced by TIPHON Release 4 definitions [26]. These aspects of the process drew upon but were not constrained by the stage 1 elements of the familiar ISDN three-stage standardization process. A complete application of that process was not adopted by the TIPHON project since it would lead to the recreation of an ISDN on an IP core network and that process does not align with the approaches being adopted for third generation mobile networks. Step C Step A TIPHON Release n service capability definition TIPHON Release n service independent requirements Figure A.3: Step B - Release capability definition Service capability definitions illustrated in figure A.3 are used in Step B to specify the core components expected from the network technology and associated management technology and processes to deliver the functions specified for the corresponding TIPHON Release. Where there were aspects implied for a Release that cannot be defined within a service capability definition; these requirements were captured in a statement of service independent requirements for the associated release. Service Service Capability Service Capability Service Capability Network Capability Commercial Context Service Application User Capability Figure A.4: Services and service capabilities Within the TIPHON project, end services are understood to mean functionality provided by service applications set in a commercial context. It is not the purpose of TIPHON to specify services, but to address how service applications can be constructed from sets of functionality. In line with the approach adopted by Third Generation networks, the focus is on the definition of user and network capabilities that may be assembled into service capabilities. Whilst the support of third generation network services is seen as desirable, such support is not a mandatory requirement of the TIPHON process. The service abstraction layer described in TR 101 877 [42] is defined by a modular and extensible set of service capabilities. TIPHON Release 4 has defined service capabilities using class notation [Booch] instead of the service style used in previous TIPHON releases. This formalized approach allows design tools e.g. UML to be used in the synthesis and animation of services. These service capabilities can be distributed over a number of service domains, as has been shown in TR 101 877 [42]. These domains that must be interconnected so that the distributed capabilities can be combined to make up the end-to-end service application. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 27 TIPHON structures concerns using the concepts of domains and functional groups and the following clauses introduce a number of concepts necessary to define service capabilities in the context of domains and their interconnection. A.4.1 Domains A domain is defined as a collection of physical or functional entities which share a consistent set of policies and common technologies. This concept of domain was the basis for TIPHON protocol harmonization. A domain exposes a consistent set of interfaces to other domains in an appropriate technology. An implementation of this domain with equipment may expose one set of technologies (i.e. protocols) to one domain and another set of technologies to another. An administrative domain is defined as a collection of physical or functional entities under the control of a single administration. This is a business concept and only of relevance in TIPHON to scope further definitions. In TIPHON systems three kinds of domains are identified and defined as: • End-user domain: A collection of physical or functional entities under the control of an end-user, which share a consistent set of policies and common technologies. • Service domain: A collection of physical or functional entities offering IP telephony services under the control of an IP Telephony Service Provider (ITSP) which share a consistent set of policies and common technologies. • Transport Domain: A collection of transport resources sharing a common set of policies, QoS mechanisms and transport technologies under the control of a Transport Network Operator (TNO). The technology within each domain provides a number of functions. It is the behaviour of those functions, which is described by Service Capabilities. A.4.2 Functional groups TIPHON groups functions that often occur together in functional groups which are collections of functional entities within a domain. In TIPHON, system functional groups are used to structure the necessary functionality to offer IP telephony services across domains. The TIPHON Release 4 architecture [25] defines reference points that describe the communication between the functional entities between and within these functional groups. Each Domain may contain one or more functional groups. Since a domain is always is part of one administrative domain, it is implicit in this hierarchy that a functional group has only one "owner". It is the "owner" who sets the policy that is applied to technology to create a domain. The owner also decides which service capabilities shall be provided by each functional group. Functional groups have notions of both ownership and of place in the topology of a call. This means that there is a difference between the originator and the terminator and the roles of intermediate functional groups. In order to specify service capabilities the behaviour is described in terms of ownership and topology but independent of the technology so functional groups are used rather than domains for this purpose. Functional groups that are used to connect calls from one terminal to another are called network functional groups. In some instances a network functional group will be used to originate calls and at other times to terminate them. The behaviour required will depend on the location of the network functional group in the call topology. For calls involving two parties there will be an originating network functional group and a terminating network functional group. It may occur that the originating and terminating network functional groups are in the same domain, or even in the same set of equipment, but the general case is still used for specification purposes. The behaviour of a functional group is determined by whether it is aware of the service application and hence the context in which the service capabilities are being used. A.4.3 Introduction to the TIPHON transport plane The TIPHON environment addresses the case where multiple networks, possibly employing differing network technologies, interwork to provide end-to-end communications services as shown in figure A.5. This model supports the different business roles found within the heterogeneous communications environment envisaged by TIPHON described in TR 101 877 [42] and commonly found in modern public communications networks. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 28 Network Abstraction Layer Transport Abstraction Layer Service Abstraction Layer Terminal Domain #1 Terminal Domain #2 Access Domain#1 Transit Domain#1 Access Domain#2 Transit Domain#2 Service Application Layer TIPHON Application Plane TIPHON Transport Plane Transport Plane/Application Plane Interface Figure A.5: The TIPHON network and service environment model The TIPHON network and service environment model is separated into two planes that exist across the various network domains encountered in the end-to-end communications path. These two planes connect with a Management Plane, shown in figure A.6, which exists outside of the TIPHON network and service environment. Management Plane Transport plane Transport Plane SCN Plane Application Plane Figure A.6: TIPHON planes As shown, the upper plane comprises the service application and service abstraction layers and is termed the TIPHON application plane. This plane addresses the implementation of end-to-end communications applications. The lower plane includes the transport and network abstraction layers and is termed the TIPHON transport plane. The TIPHON transport plane provides domain independent communications capabilities to the TIPHON application plane. Requirements placed upon the TIPHON transport plane by the TIPHON application plane are expressed in service independent requirements documents in accordance with the TIPHON project method described in TR 101 835 [1]. TR 101 311 [43] describes sets of service independent requirements that specify the required behaviour of the TIPHON transport plane. The TIPHON application plane is expressed in terms of service applications and service capabilities. A.5 Reference architecture (Step C) The outputs from both Step A and Step B form the source documents for Step C that develops a reference architecture in support of the release. The reference architecture shall be developed independently of underlying technology issues where possible and represents a static design for the release. In support of the reference architecture, management and network information flows are developed to express the dynamic behaviour of the system. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 29 Step D Step B Step A TIPHON Release n Abstract architecture and reference points Network Information flows, SDL and UML Management Information flows, SDL and UML Figure A.7: Step C - Development of the reference architecture End-user domains can have two kinds of functional groups: • A terminal functional group represents all the IP telephony functionality within a user's terminal and may be classified as originating or terminating based upon their location within the topology of a specified call. • A terminal registration functional group represents the registration functionality within the user's terminal. Service domains can have the following kinds of functional groups: • A network functional group contains the functionality required to establish a call between two terminals, a gateway and a terminal or two gateways and may be classified as originating or terminating based upon their location within the topology of a specified call. • A gateway functional group contains the functionality of a network functional group and additional functionality needed to connect calls to the SCN and may be classified as originating or terminating based upon their location within the topology of a specified call. A service domain or a constituent functional group which is aware of the service application, and hence the user contract and context of the service capabilities, is denoted by the use of the term "home". If the access service domain to which the user is attached is not the "home" for the user then that access originating network functional group, is defined as the "serving" network functional group. in the case of the transit service domains in figure 6 one of them will be the "home" service domain. A.5.1 Service capability example In the following example taken from TS 101 878 [44], there are three service capabilities, A, B and C. These are distributed across the TIPHON network and service environment model and instantiated as Co, CT2 and CT, etc. These service capabilities are shown as instances within domains. The behaviour defined by service capabilities is actually exhibited by the functional groups that make up the domains. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 30 Access Service Domain Transit Service Domain #2 End-Usert Domain End-Usero Domain Access Service Domain Ao Bo Co At Bt Ct Atr Ctr Btr Bao Aao Bat Aat Figure A.8: Service capabilities interworking across domains In figure A.8, the behaviour of the service capabilities A, B and C are defined. Service capabilities A and B behaviours are shown in each of the domains. Service capability C is shown as having no behaviour other than message conveyance within the access service domains but behaviour is defined (Ctr) in the end-user and transit service domains. A.5.2 User roaming considerations In the TIPHON approach, each service provider creates their own service offering. This service offering will consists of any number of service applications possibly bound by one user Name. In deployments where a user may roam on other networks, the visited network may not understand the particulars of service application that users wish to use and may even not understand the naming scheme used, and in this case all signalling will have to pass through the home network. Visited domains will only relay signalling to and from the appropriate (home) domain and (possibly) creation of bearers. For some service applications such as public telephony, it may be necessary for visited networks to support some additional functionality such as emergency calls because this essential service needs to be provided locally since it requires access to local information and/or local points of connection. The network functional group represents all of the functionality of an IP-based application in support of the call. In environments where users roaming does not take place the originating end-user always has a contract with the IP telephony service provider controlling the service domain containing the originating network functional group and the terminating user with the IP telephony service provider controlling the service domain containing the terminating network functional group. The network functional group which acts as the "home" for the originating user is the originating home network functional group. Whilst the registration function is related to the functional groups described as "home", it need not be co-located with it or part of it. For user roaming considerations this may not be the case. Therefore network functional groups are further divided into serving network, intermediate and home network functional groups where these are defined: • Serving network functional group enables terminal functional groups to connect to a service IP telephony service provider and represents the functions required to enable the user to register and to use services provided by the home network functional group. • Intermediate (transit) functional group connects the serving network functional group to the home network functional group. (The intermediate network functional group is only present when the serving network functional group and the home network functional group are not directly connected.) ETSI ETSI TR 101 301 V3.1.1 (2004-04) 31 • Home network functional group is aware of the service application subscribed to by the end-user. Home network functional groups may be classified as originating or terminating based upon their location within the topology of a specified call. The home network functional group and the serving network functional group may reside in the same service domains or different service domains. It was not assumed that signalling and media follow the same path through packet switching systems. Serving network functional grouping Terminal registration functional grouping Home network functional grouping Intermediate network functional grouping Figure A.9: Overview of functional groups involved in registration Figure A.9 shows the functional groups involved with the registration process: • The terminal registration functional group represents the functionality of the registering terminal. • The serving network functional group represents the functions required to enable the user to register and to use services provided by the home network functional group. • The intermediate functional group connects the serving network functional group to the home network functional group. • The home network functional group represents functionality relating to the user's profile and subscription. A.5.3 TIPHON Scenario 0 functional groups Scenario 0 is the all-IP scenario whereby all functional groups are on the IP network. Figure A.10 shows the possible functional groups involved in a Scenario 0 call. Originating network FG Transit FG Terminating network FG Terminating terminal FG Originating terminal FG Figure A.10: TIPHON Scenario 0 without users roaming Figure A.10 shows symmetry about the Intermediate (transit) functional group at the centre of each reference configuration. This may be the typical scenario. The minimum extreme case is where the originating and terminating network function groups are the same, in that case there is no intermediate network functional group. A maximum extreme case there is multiple intermediate network functional groups. The cases of one or both of the users is roaming is elaborated by adding the relevant roaming users part to the diagram in figure A.11. The actors in terms of domains which have differing behaviour are depicted for the extreme case by the following functional groups: Originating Terminal FG Transit FG Terminating Terminal FG FG Origi- nating Home FG Serving FG Termi- nating Home FG Transit FG Transit FG Serving FG Figure A.11: TIPHON Scenario 0 with both users roaming ETSI ETSI TR 101 301 V3.1.1 (2004-04) 32 A.5.4 TIPHON Scenario 1 functional groups Scenario 1 differs from Scenario 0 because the terminating side functions are handled in the SCN behind a gateway network functional group. From the point of service capabilities the domain containing the gateway exhibits all of the service capabilities associated with the called party. The list of the actors for Scenario 1, in terms of domains which have differing behaviour are depicted by the following functional groups: Origi- nating Terminal FG Originating Network Transit FG Termi- nating Gateway FG FG Figure A.12: TIPHON Scenario 1 - simple case Origi- nating Terminal FG Transit FG Terminating Gateway FG Origi- nating Home FG Serving FG Transit FG Figure A.13: TIPHON Scenario 1 - originating user roaming A.5.5 TIPHON Scenario 2 functional groups Scenario 2 differs from Scenario 0 because the functions on the Originating side are handled inside the originating gateway. From the point of service capabilities, the domain containing the gateway exhibits all of the service capabilities associated with the calling party. The list of the actors for Scenario 2, in terms of domains which have differing behaviour are depicted by the following functional groups: Origi- nating Gateway FG Transit FG Termi- nating Network Termi- nating Terminal FG FG Figure A.14: TIPHON Scenario 2 - simple case Origi- nating Gateway FG Transit FG Termi- nating Terminal FG Termi- nating Network FG Transit FG Serving FG Figure A.15: TIPHON Scenario 2 - terminating user roaming A.5.6 TIPHON Scenario 3 functional groups Scenario 3 bypasses SCN long distance via an IP network. The simple form occurs when neither user has a service instance in a TIPHON network. The complex case is similar to Scenario 2 but the call is diverted to another network via a gateway. The list of the actors for Scenario 3, in terms of domains which have differing behaviour are depicted by the following functional groups: ETSI ETSI TR 101 301 V3.1.1 (2004-04) 33 Originating Gateway FG Transit FG Terminating Gateway FG Figure A.16: TIPHON Scenario 3 - simple case Originating Gateway FG Transit FG Terminating Gateway FG Termi- nating Home FG Transit FG Figure A.17: TIPHON Scenario 3 - terminating user roaming A.6 Implementation framework (Step D) For a given TIPHON Release, the reference architecture and associated network and management information flows will be mapped into individual protocol and management frameworks, as indicated in figure A.18. The frameworks identify key interfaces and establish requirements for information flows over each interface. These frameworks are the essential means by which the TIPHON project remains protocol neutral to the last point in specification development - ensuring that the complex interworking issues addressed by the project can be fully explored independently of technology constraints. Once the interface requirements have been produced, they are then mapped into a given technology through technology mapping and compliance definitions. Step E Step B Step A Step C TIPHON Release n Protocol Framework Definition TIPHON Release n Management Framework Definition TIPHON Release n Interface Protocol Requirements Definitions TIPHON Release n Management Interface Requirements Definitions Figure A.18: Step D implementation framework ETSI ETSI TR 101 301 V3.1.1 (2004-04) 34 TS 101 882 [24] defines the framework for protocols to fit into in order to be considered as compliant to TIPHON. Information flows and reference points for application of the TIPHON functional architecture for inter-domain services are described in TS 101 315 [45]. The requirements for the protocol framework are described in the TIPHON abstract architecture TS 101 314 [25] and are required to implement the capabilities described in TS 101 878 [44]. The framework is written in the form of a set of meta-protocols described both in syntax using Abstract Syntax Notation 1 (ASN1) [46] and in behaviour using Message Sequence Charts (MSC) [46] and simple Specification and Description Language (SDL) diagrams [46]. The meta-protocols show both the service primitives used by higher or lower layers to invoke, control and report on the progress of the meta-protocol, and the meta protocol message units used to communicate with peer entities. Meta-protocols are described in TS 101 882 [24] for the following reference points defined in TS 101 314 [25]: S, N, C, T, R and M applicable to the protocols implemented by equipment fulfilling the roles that are necessary to support TIPHON Release 4. The meta protocol message units map to Protocol Data Units (PDUs) or equivalent message types in candidate protocols. The service primitives map to either Application Programming Interface (API) calls or to protocol primitives in candidate protocols. Interoperability of candidate protocols to the outlined meta-protocols can be achieved by converting the native syntax of the candidate protocol to ASN.1 and by describing the relationship between the native behaviour of the candidate protocol and the behaviour described for each meta-protocol. A service interaction diagram of the TIPHON planes as defined in TS 101 314 [25] is given in figure A.19. The planes and the functional entities they contain communicate across a set of Service Access Points (SAPs) for each of TIPHON Call Control (TCC), TIPHON Registration (TR), TIPHON Transport (TT), and TIPHON Lower Layers (TLL). Above the TCC-SAP and TR-SAP is the user or service plane that may invoke functions and features in the application plane in a number of ways thereby defining user services. TS 101 882 [24] specifies the primitives and Meta Protocol Message Units for the registration and call control functions in the application plane, and provides a description of the transport plane primitives and behaviour. The intention of the meta-protocol design description is to be independent of network technology. The terminology used throughout is deliberately abstract; functional entities are numbered, with an indication of the probable functional grouping to which they belong. This method of description allows for open mapping to the functionality of the entity and places no restrictions on the application of any functional entity to alternative functional groupings. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 35 Transport plane TT-SAP Application plane Call Control Registration TCC-SAP TR-SAP TLL-SAP TCC-SAP: TIPHON Call Control Service Access Point TR-SAP: TIPHON Registration Service Access Point TT-SAP: TIPHON Transport Service Access Point TLL-SAP: TIPHON Lower Layer Service Access Point Figure A.19: The TIPHON inter-planar service interfaces The TT-SAP enables the transport of both QoS optimized media types and non-QoS optimized signalling and media types. Examples of QoS optimized media transport include: speech; and, broadcast video. Examples of non-QoS optimized media transfer include: file transfer, e-mail and signalling. The SAPs carry service primitives in the manner shown in figure A.20. Protocol/Functional Entity Protocol Transport Request Confirm Primitives at SAP Function A Function B Protocol Entity Response Indication Primitives at SAP Protocol Entity Protocol/Functional Entity Figure A.20: Relationship of functional entities, primitives and protocols The entities involved in peer-to-peer relationships may be located in networks that are under the same or different Administrative control. For the purposes of testing and verification the meta-protocols shall be considered as visible at application specific reference points as described in TS 101 314 [25]. Candidate protocols may map, as appropriate, many of the meta-protocols relevant to application specific reference points described in TS 101 314 [25] to candidate protocols relevant to a single reference points in their native environment. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 36 The data transfer within a single physical entity, represented as primitives between functional entities, may not be visible externally and may therefore not be explicitly testable or capable of being mapped by candidate protocols. For the network technology elements, the protocol framework is developed to provide an identification of the key interfaces required in a system that is compliant with the specific TIPHON release. For each interface identified, detailed requirements state the behaviour that is to be provided across the interface. A.6.1 Basic call example In this clause, the general model outlined in the previous clause is applied. It shows how the model may be used and applied in real-world situations. It starts with providing a general model of the states in a telephone call, loosely based on the ITU-T Recommendation Q.931 [47] and Intelligence Network (IN) call state models. Next, this is extended for supplementary services and multi-domain services to show how robust the model is and how it can be refined to provide these services. The basic telephone call consists of a number of activities that have to occur before the call can be set up: 1) The call is initiated. 2) The call is authorized by the service provider. 3) The call is routed towards the destination. 4) Call associated bearers are set up. 5) Media flows are established for the bearers. 6) Appropriate transport is arranged for the media flows. 7) The call and bearer requests are forwarded to the next domain (or terminal). 8) The call is accepted by the recipient. 9) The media flows. 10) The call is torn down, and along with it the bearers, media and transport are torn down. Figure A.21 shows these steps in a schematic way. These 10 steps are usually taken in this order to retain the feel of the realization in the SCN. If this sequence is not followed, the perceived post-set-up delay (i.e. the time from receiver pick- up to media establishment) would be very large or the first few seconds of speech may be choppy because the speech is sent "best-effort". The routing request flow performed in step 3 allows any intelligent routing mechanism including number portability and intelligent routing schemes to be hidden. Note that the bearer is set up in three phases: a) in the fist phase the originator offers his capabilities for sending and receiving and commits to receive what was offered; b) in the second phase the remote side has answered and offered its capabilities and the appropriate reverse stream can be prepared; c) in the third phase the (reverse) speech channel is opened when the call has been accepted. The service provider can enforce the access policy in the third phase. Using the information flows down to the transport plane and up to the service control we can implement strict access and usage control in both the transport plane (it can block any non-authorized streams) and in the application plane (it can try and authorize users before committing resources). ETSI ETSI TR 101 301 V3.1.1 (2004-04) 37 Domain 1 CC BC SC MC SE Domain 2 SC CC BC MC SE Domain 3 CC BC SC MC SE Service Control Call Control Media Control Bearer Control Services Packet transport 1 2 2 3 3 4 5 6 4 7 8 10 7 9 Figure A.21: Schematic call set-up diagram A.7 Technology mapping and verification (Step E) The completed interface definitions were mapped into the technologies supported by release 4 of the TIPHON project. This was achieved by providing an appropriate profile of the technology for a given interface, as shown in figure A.22. Where a technology fully meets the requirements for a specific interface, a protocol profile will be produced for that protocol which defines its use in implementing that interface. However where a specific technology does not support the required functionality, the mapping will not be able to generate a profile - as shown in the case of Technology A in figure A.22 for interface "q". For such cases, the requirements identified for the interface may be used as the basis of extensions to the technology in question. TIPHON Release n interface protocol Requirement q TIPHON Release n interface protocol Requirement k TIPHON Release n interface protocol Requirement z TIPHON Release n protocol framework Technology mapping and compliance (Technology B) Technology mapping and compliance (Technology A) Figure A.22: Step E - Network technology mapping In a similar manner, the management framework is developed and mapped via management interfaces onto supporting technologies as shown in figure A.23. As with the network technology framework, the process of mapping will expose any deficiencies in the underlying technology. In the example shown, Technology A is found to meet the requirements for management interfaces "k" and "z" but does not meet the requirements for interface "q". This contrasts with ETSI ETSI TR 101 301 V3.1.1 (2004-04) 38 Technology B which is able to meet the requirements for all three interfaces shown through appropriate profiles as indicated. TIPHON Release n Management Interface Requirement q TIPHON Release n Management Interface Requirement k TIPHON Release n Management Interface Requirement z TIPHON Release n Management Framework Technology Mapping & Compliance (Technology B) Technology Mapping & Compliance (Technology A) Figure A.23: Step E - Management technology mapping Having developed the network technology and management frameworks and mapped them to specific technologies, appropriate Protocol Implementation Conformance Specifications (PICS) must be constructed to ensure the profiles are implemented correctly. A.7.1 Mapping to standard protocols and entities In this clause the functional architecture and its flows are mapped back to real-world standard protocols and fit into the architecture. Figure A.24 gives a high-level overview of the well known protocols (H.323, SIP and BICC) and their mapping to the architecture model. The figure shows physical elements (terminal, softswitch, media gateway etc.) and protocols between them mapped to the layers in the architecture model: • The H.323 communication is represented by the labels H.225 [48], H.245 [49] and H.248 [50]. • The SIP communication is represented by the labels SIP [23] and SDP [51] and MEGACO [50] [52] (which is an alternative name for H.248). • The BICC communication is labelled by the BICC label, BICC also uses H.248 for the vertical interface. TIPHON Release 4 describes the mapping of the basic call to these H.323 and SIP protocols in [53], [54] and [55]. An example is described below. An IP-based user end point (terminal, SIP server etc.) can communicate with a network service entity, as a front end, another network entity performs the back-end functionality of call admission control and call routing. An interconnect element is implemented as a controllable firewall/media gateway to be controlled by the first network element. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 39 MG control SC CC MGW BC MC SC CC SE BC CC SC SE BC MC Terminal/ SIP client SC CC SE BC Gatekeehper SIP Server/ SoftSwitch MD Gatekeeper/ SIP Server/ SoftSwitch RTP H.225 (RAS) SIP H.225 (Q.931) SIP H.245 SDP RTP Sig-GW SC CC H.225 (RAS) H.225 Ann G H.225.0 (Q.931) SIP, BICC H.245 SDP H.248/MEGACO H.225 (RAS) H.225 Ann G H.225.0 (Q.931) SIP, BICC H.245 SDP ISUP/Q.931 INAP Gateway Media Control Bearer Control Call Control Service Control Services MC Packet Transport Plane H.248/MEGACO PSTN Figure A.24: Mapping to physical entities and protocols Step B Step A Step D TIPHON Release n Security Analysis and Compliance Specification TIPHON Release n Protocol Implementation Conformance Specification TIPHON Release n Technology (A) Mapping and Compliance Figure A.25: Step E - Conformance specifications and security analysis The final element of Step E completes the security analysis and compliance specification, and acts as a final check on the release to ensure security and integrity issues have been correctly addressed [57], [58] and [59]. Figure A.26 provides an insight into the testing methodology and associated documentation. Figure A.26: Testing methodology and associated documentation ETSI ETSI TR 101 301 V3.1.1 (2004-04) 40 The Implementation Conformance Statement (ICS) is a checklist of the capabilities supported by the Implementation Under Test (IUT). It provides an overview of the features and options that are implemented. The ICS can be used to select and parameterize test cases and as an indicator for basic interoperability between different products. See EG 201 058 [60] ICS proforma style guide. The Test Suite Structure and Test Purposes (TSS&TP) are derived from the relevant base standards. They provide an informal, easy-to-read description of each test, concentrating on the meaning of the test rather than detailing how it may be achieved. Test Purposes are grouped into a logical Test Suite Structure according to suitable criteria (e.g. basic interconnection, error handling, functionality etc.) (see ETR 266 [61] Test Purpose style guide). The Abstract Test Suite (ATS) is the entire collection of Test Cases. Each Test Case specifies the detailed coding of the Test Purposes, written in the standardized test specification language TTCN. See EG 202 103 [62] Guide for the use of TTCN-2 and ETR 141 [63] TTCN style guide. The Implementation eXtra Information for Testing (IXIT) contains additional information (e.g. specific addresses, timer values etc.) necessary for testing. The Executable Test Suite (ETS) can be quickly and easily implemented from the ATS using the TTCN compilers available on most modern test tool platforms. ETSI ETSI TR 101 301 V3.1.1 (2004-04) 41 Annex B: Bibliography • DTS/TISPAN-06006-01-TIPHON_R4: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Technology Compliance Specification; TIPHON profile for Open Settlement Protocol (OSP); Part 1: Protocol Implementation Conformance Statement (PICS) Proforma". • DTS/TISPAN-06006-02-TIPHON_R4: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Technology Compliance Specification; TIPHON profile for Open Settlement Protocol (OSP); Part 2: Test Suite Structure (TSS) and Test Purposes (TP)". • DTS/TISPAN-06006-03-TIPHON_R4: "Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; Technology Compliance Specification; TIPHON profile for Open Settlement Protocol (OSP); Part 3: Abstract Test Suite (ATS) and PIXIT Proforma". ETSI ETSI TR 101 301 V3.1.1 (2004-04) 42 History Document history V1.1.1 March 2001 Publication (Historical) V2.1.1 February 2002 Publication V3.1.1 April 2004 Publication |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 1 Scope | The present document provides an introduction to the technical issues relating to the work items defined in the terms of reference of ETSI Project TIPHON [1] and offered with respect to the reference scenarios: Scenario 0: communication between 2 or more Internet Protocol (IP) network based users in which the call signalling and traffic are wholly contained within the IP network (in one or more domains). Scenario 1: communication between IP network based users and Switched Circuit Network (SCN) based users in which the call setup is originated by the IP network user. Scenario 2: communication between IP network based users and SCN-based users in which the call setup is originated by the SCN based user. Scenario 3: communication between SCN based users using IP based networks for the connection/trunking between the involved users. Scenario 4: communication between IP network based users using SCNs for the connection/trunking between the involved users. TIPHON shall primarily consider, but not be restricted to, the interaction of H.323 terminals on IP networks with telephone terminals on SCNs. The TIPHON project shall develop standards, and profiles of existing standards, for each of the above profiles. New standards shall be developed only where no existing standards exist. Where existing standards exist in ETSI, ITU or elsewhere ETSI Project TIPHON shall work with the standards bodies in developing and promoting profiles of those standards. These standards shall include an Open Settlement Protocol. The TIPHON project shall not specify any new bearer services. However the TIPHON project deliverables shall be able to request certain QoS constraints that may restrict the ability of any particular bearer service to support TIPHON teleservices (particularly with respect to QoS and bandwidth). The present document is structured as follows: - clause 4 provides an overview of the TIPHON project work area; and - clause 5 introduces and describes the reference scenarios of the TIPHON project. The present document will not provide solutions for the technical issues that are identified therein. |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 2 References | The following documents contain provisions which, through reference in this text, constitute provisions of the present document. • References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific. • For a specific reference, subsequent revisions do not apply. • For a non-specific reference, the latest version applies. • A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same number. [1] Terms of Reference ETSI Project TIPHON; http://www.etsi.org/tiphon [2] ITU T Recommendation I.112: "Vocabulary of terms for ISDNs". [3] ITU T Recommendation I.210: "Principles of telecommunication services supported by an ISDN and the means to describe them". ETSI ETSI TR 101 300 V2.1.1 (1999-10) 6 [4] ITU T Recommendation E.164: "The international public telecommunication numbering plan". |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 3 Definitions and abbreviations | |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 3.1 Definitions | For the purposes of the present document, the following terms and definitions apply. bearer service: type of telecommunication service that provides the capability for the transmission of signals between user-network interfaces. See ITU-T Recommendation I. 112 [2], subclause 2.2 definition 202 NOTE 1: The ISDN connection type used to support a bearer service may be identical to that used to support other types of telecommunication service. demand service, demand telecommunication service: type of telecommunication service in which the communication path is established almost immediately, in response to a user request effected by means of user-network signaling E.164 number: number conforming to the numbering plan and structure specified in ITU-T Recommendation E.164 [4] H.323 terminal: entity which provides audio and optionally video and data communications capability in point-to-point or multipoint conferences in packet-based networks Integrated Services Digital Network (ISDN): see ITU-T Recommendation I.112 [2], subclause 2.3 definition 308 IP number: number conforming to the structure of addresses in IP networks ISDN number: number conforming to the numbering plan and structure specified in ITU-T Recommendation E.164 [4] service, telecommunication service: that which is offered by an Administration or ROA to its customers in order to satisfy a specific telecommunication requirement NOTE 2: Bearer service and teleservice are types of telecommunication service. Other types of telecommunication service may be identified in the future. supplementary service: see ITU-T Recommendation I.210 [3], subclause 2.4 Switched Circuit Network (SCN): telecommunications network, e.g. Public Switched Telephone Network (PSTN), Integrated Services Digital Network (ISDN), and General System for Mobile communications (GSM), that uses circuit- switched technologies for the support of voice calls. The SCN may be a public network or a private network teleaction service [telemetry service]: type of telecommunication service that uses short messages, requiring a very low transmission rate, between the user and the network NOTE 3: Examples of teleaction services are: telealarm, telecommand, telealerting. teleservice (telecommunication service): type of telecommunication service that provides the complete capability, including terminal equipment functions, for communication between users according to protocols established by agreement between Administrations and/or RPAs. See ITU-T Recommendation I.112 [2], subclause 2.2 TIPHON compliant system: system that complies with the mandatory requirements identified in the TIPHON requirements documents together with compliance to the parts of the TIPHON specifications in which these requirements are embodied: • TR 101 306 (for compliance with TIPHON phase 1); • TR 101 307 (for compliance with TIPHON phase 2); and • TR 101 308 (for compliance with TIPHON phase 3. NOTE 4: Requirements indicated 'conditional' in the documentation should be considered mandatory if the condition applies. ETSI ETSI TR 101 300 V2.1.1 (1999-10) 7 |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 3.2 Abbreviations | For the purposes of the present document, the following abbreviations apply: DECT Digital Enhanced Cordless Telecommunication DTMF Dual Tone Multiple Frequency EP ETSI Project GSM General System for Mobile communication GSTN General Switched Telephone Network IETF Internet Engineering Task Force IMTC International Multimedia Telecommunication Consortium IWF Interworking Function IP Internet Protocol ISDN Integrated Service Digital Network MMI Man Machine Interface PSTN Public Switched Telephone Network QoS Quality of Service RSVP Resource Reservation Protocol SCN Switched Circuit Network SDH Synchronous Digital Hierarchy SONET Synchronous Optical NETwork TETRA Terrestrial Trunked Radio TIA Telecommunications Industry Association |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 4 Overview | |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 4.1 Introduction | The provision of voiceband services on technologies other than circuit switching has been growing over recent years with much effort on the provision of such services on packet switching infrastructures using the Internet Protocol at layer 3 of the ISO/OSI stack. ETSI Project (EP)-TIPHON exists within ETSI to ensure that the requirements for quality of service, security, inter-domain settlement, and so forth, that arise from the abstraction of service from underlying technology applies equally to switched circuit technologies and to packet switching technologies. There is a growing market for real-time voice communication and related voiceband communication over Internet Protocol (IP) based networks. The objective of this project is to support a market that combines telecommunications and Internet technologies to enable communication between Internet Protocol (IP) based networks and networks based upon circuit switching technology. These latter networks are referred to throughout the document as Switched Circuit Networks (SCNs) and encompass the generic 64kbit/s technologies of Public Switched Telephone Network (PSTN), Integrated Services Digital Network (ISDN), Synchronous Digital Hierarchy/Synchronous Optical Network (SDH/SONET) as well as the current digital mobile and wireless technologies including, but not restricted to, Global System for Mobile communications (GSM), TIA/EIA-136, IS-95, PDC, Terrestrial Trunked Radio (TETRA) and Digital Enhanced Cordless Telephony (DECT). The overall structure of TIPHON can be summarized in figure 1. ETSI ETSI TR 101 300 V2.1.1 (1999-10) 8 End to end service SCN SCN IP IP Network of networks with inter domain settlement Figure 1: Overview of TIPHON problem domain The TIPHON problem domain can be drawn as a network of networks where the constituent networks may be based upon IP or Circuit Switching technologies. The TIPHON scenarios lie over these networks and establish a means of providing guaranteed end-to-end Quality of Service (QoS) and consistent inter-domain Security capabilities. In addition TIPHON ensures that service users and providers are able to call upon standardized inter-domain settlement protocols. - Quality of service mechanisms may be defined within TIPHON to satisfy user requirements on the desired quality of audio and video transmissions. - Security mechanisms may be defined within TIPHON to satisfy user requirements for privacy, authentication and accountability. A TIPHON compliant system can then be defined as an upper layer network and transport function offering telephony service over a set of underlying lower layer networks. Services in a TIPHON compliant system shall be treated in like manner to existing regulated speech services and shall therefore encompass provision of facilities that ensure compliance with national and regional regulations for privacy (including data protection), lawful interception, and accountability. In addition TIPHON standards shall be developed to meet the requirements arising from the provision of lifeline services which include availability, repudiation services and integrity services. Finally TIPHON standards shall be developed to ensure that national and international regulations (current and planned where practicable) for subscriber number and service portability are supported. The following assumptions shall apply as guiding principles for TIPHON: - TIPHON compliant terminals may be PC-like or telephone-like; - the Man Machine Interface (MMI) of the terminal shall tend towards that of a telephone; - operation of a TIPHON terminal shall tend towards that of a telephone (and shall therefore encompass single stage dialling, network type abstraction); - subscribers may move their access technology yet retain the same grade of service and same QoS. ETSI ETSI TR 101 300 V2.1.1 (1999-10) 9 |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 4.2 Teleservices and Bearer Services in TIPHON | TIPHON compliant systems need only support ONE of the following teleservices in IP networks: - point-to-point speech; and - point-to-multipoint speech. NOTE: For the purposes of the present document speech encompasses all voiceband services including G3 fax. |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 5 Reference scenarios | To better address the scope of the project the following reference scenarios are described: Scenario 0: communication between 2 or more IP network based users in which the call signalling and traffic are wholly contained within the IP network (in one or more domains). Scenario 1: communication where the source is on an IP network and the destination is on an SCN network. Scenario 2: communication where the source is on an SCN network and the destination is on an IP network. Scenario 3: communication where the source and destination are on different SCN networks where an IP transit network is used. Scenario 4: communication where the source and destination are on different IP networks where an SCN transit network is used. NOTE 1: With the introduction of mobility as a service applied within (or enabled from) TIPHON it is possible for more than one of the above scenarios to apply in a call. NOTE 2: Interworking functions (IWF) can be implemented separately from or integrated into the existing SCN or IP-based network in order to provide the required interoperability. NOTE 3: The term "IP network" does not specifically denote the Internet. NOTE 4: "SCN" represents the set of networks characterized as "circuit-switched" networks. The diagrams in subclauses 5.1 through 5.5 demonstrate the reference scenarios to be examined by TIPHON. The scenarios should be viewed with respect to the network technology applied to the origination, backbone (or transit), and termination network elements. This is shown diagrammatically in figure 2 and textually in table 1. ETSI ETSI TR 101 300 V2.1.1 (1999-10) 10 Origination Backbone Termination SCN IP SCN IP SCN IP 1. 2. 3. 4. 5. 6. 7. 8. Figure 2: Inter network scenarios in a TIPHON environment. The TIPHON reference scenarios can be mapped to the cases of figure 2 as shown in table 1. Table 1: Inter network connection cases Case Origination Backbone Termination Scenario 1 IP IP IP 0 2 IP IP SCN 1 3 IP SCN SCN 1 4 IP SCN IP 4 5 SCN IP SCN 3 6 SCN IP IP 2 7 SCN SCN IP 2 8 SCN SCN SCN Note NOTE: Case 8 is outside the scope of TIPHON. Each of the above cases introduces technical problems that have to be resolved. These technical issues include but are not restricted to the items described in table 2. ETSI ETSI TR 101 300 V2.1.1 (1999-10) 11 Table 2: Technical issues arising from TIPHON scope Technical issue Notes Scale Individual terminal, through small PABX or LAN, to large trunked IP or SCN. Provision of common service irrespective of connected network size. Inter-technology address resolution IPv4 and IPv6 to E.164 for direct dial service. Service to technology abstraction Technology independent service provision (where QoS and other public service constraints can be met). Inter-technology billing and settlement Billing per unit time for fixed resource on SCN (current European model) versus packet rate or bandwidth on IP. QoS End-to-end and inter-technology. May include how to provide resource guarantee on IP connections to SCN. Provision of policy and protocols applicable to any underlying network service. Protocol harmonization Abstraction of service interaction from network implementation of service. Public service constraints Lawful interception of communication, emergency service calling. This includes the ability to identify the location from which a call is being made. Optimized routing To maximize QoS by service or by information element. Each of these issues is addressed progressively in each of the five reference scenarios and by provision within the layered architecture. A set of policies may be used to tailor the service and to provide a profile for each of the technical issues. |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 5.1 Scenario 0 | IP Network H.323 terminal IP Access Access H.323 terminal IP Access Access Figure 3: Scenario 0, IP-Phone to IP-Phone on IP network ETSI ETSI TR 101 300 V2.1.1 (1999-10) 12 |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 5.2 Scenario 1 | Call initiated from IP Network to SCN SCN IP Network IWF Local or distributed function H.323 terminal Phase I Phase 1 IP Access Access Figure 4: Scenario 1, Source on IP network to destination on SCN network |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 5.3 Scenario 2 | Call initiated from SCN to IP Network IP Network IWF Local or distributed function H.323 terminal Phase I Phase 1 IP Access SCN Figure 5: Scenario 2, Source on SCN network to destination on IP network ETSI ETSI TR 101 300 V2.1.1 (1999-10) 13 |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 5.4 Scenario 3 | IP Network IWF Local or distributed function Phase I Phase 1 IWF Local or distributed function SCN SCN Figure 6: Scenario 3, Source and destination on SCN network using an IP transit network |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 5.5 Scenario 4 | IP Network IP Network IWF Local or distributed function Phase I Phase 1 IWF Local or distributed function H.323 terminal IP Access H.323 terminal IP Access PSTN/ISDN IP Network SCN Figure 7: Scenario 4, Source and destination on IP network using an SCN transit network |
6c7973dc25d2150f058243c003fb38a9 | 101 300 | 6 TIPHON releases | TIPHON is a complex project. In order to provide a route to the market EP-TIPHON shall publish TIPHON deliverables as a series of releases. Each release shall encompass a set of functionality as shown in table 3. ETSI ETSI TR 101 300 V2.1.1 (1999-10) 14 Table 3 Release number Due date Content 1 12/98 Scenario 1, inter-technology-domain basic call 2 12/99 Scenario 1-4, inter-domain basic call with basic features (e.g. CLI) Real time fax/data Best effort (in controlled environment) Basic security Basic OA&M Aimed at a demonstrator. 3 12/00 QoS signalling/Firewall control Enhanced security following threat analysis. Extended OA&M Additional features, service mechanisms and benchmark services INAP feature access ISUP based service interaction, e.g. CCBS Number portability Carrier preselection User mobility, terminal mobility, and radio access aspects 4 12/01 Terminal Aspects Multimedia The intention of these releases is to provide guidance for the setting of priority to work items in each working group and to provide guidance to the market. ETSI ETSI TR 101 300 V2.1.1 (1999-10) 15 Annex A (informative): List of deliverables The Work Programme of EP-TIPHON is maintained and available to view at http://www.etsi.org/ewpweb. ETSI ETSI TR 101 300 V2.1.1 (1999-10) 16 Annex B (informative): Working principles The working methods and principles applied to the development of standards for switched telecommunications and to the development of standards for Internet Protocol based packet communication have been different. TIPHON seeks to create an environment which is attractive to contributors from both sides by seeking to establish an atmosphere of co-operation and openness leading to high quality deliverables in the appropriate time frame. This is to be achieved by: - acceptance of contributions from ETSI members and invited non-ETSI members; - open availability of working and published documents via e-mail distribution lists; - easy access to ETSI's FTP server where all Temporary Documents (TDs) and Permanent Documents (PDs) are provided on-line. NOTE: This applies only within the restrictions of ETSI's rules of procedure. - short time schedules and frequent meetings; - verification, demonstration and implementation in parallel to standards production. ETSI ETSI TR 101 300 V2.1.1 (1999-10) 17 Annex C (informative): Collaborative Activities In addition to EP-TIPHON several other organizations are working in closely related areas that may support the overall objectives of TIPHON. The objective of collaboration is to avoid overlapping and assure a complete coverage of the area: technically and geographically. Within ETSI the following technical bodies have been identified as potential collaborators: - SPAN (Services and Protocols for Advanced Networks); - SMG (Special Mobile Group); - UMTS (Universal Mobile Telecommunications Service); - 3GPP (3rd Generation (mobile) Partnership Project); - TETRA (Terrestrial Trunked Radio); - ECMA TC32; - MTA (Multimedia Terminals and Applications); - ATA (Analogue Terminals and Access); - STQ (Speech processing, Transmission and Quality aspects); - DTA (Digital Terminals and Access); and - SEC (Security). Outside ETSI the following technical bodies have been identified as potential collaborators: - ITU-T (including but not restricted to SG-2, SG-11, SG-12, SG-15, SG-16); - IETF; - IMTC; - EURESCOM; - ISO/IEC JTC1/SC6/WG6; - 3G.IP. These lists may change by addition or deletion as collaborative activities and partners are identified. ETSI ETSI TR 101 300 V2.1.1 (1999-10) 18 Annex D (informative): Marketing Activities The objective is to produce specifications that have a global acceptance from industry, administrators and regulators, and other standards bodies. To support this a number of marketing activities are performed including press releases, press conferences, presentations in conferences and the use of a unique logo. For details of use of the logo see the ETSI TIPHON web site (http://www.etsi.org/tiphon). ETSI ETSI TR 101 300 V2.1.1 (1999-10) 19 History Document history V1.1.5 December 1998 Publication V2.1.1 October 1999 Publication |
e182c81fd1e4596e5b513a391752528a | 101 295 | 1 Scope | The present document describes a set of transformation rules to convert an ASN.1 94 module which uses of the features defined in X.680 [1], X.680 Amendment 1 [2], X.681 [3], X.681 Amendment 1 [4], X682 [5] and X.683 [6], into an equivalent or partially equivalent module which uses only the ASN.1 language features defined in X.680 [1]. In addition to the generic transformation rules defined in main body of this report there are two language specific appendices which provide additional transformation rules for SDL Z.105 [8] and TTCN Edition 2 as defined in ISO/IEC 9646-3 [10] respectively. The present document complements rather than supplants ETR 60 [13] and Z.105 [8]. |
e182c81fd1e4596e5b513a391752528a | 101 295 | 2 References | The following documents contain provisions which, through reference in this text, constitute provisions of the present document. • References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific. • For a specific reference, subsequent revisions do not apply. • For a non-specific reference, the latest version applies. • A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same number. [1] ITU-T Recommendation X.680 (1994): "Information technology-Abstract Syntax Notation One (ASN.1): Specification of basic notation". [2] ITU-T Recommendation X.680 Amendment 1 (1994): "Information technology-Abstract Syntax Notation One (ASN.1): Specification of basic notation: Rules of extensibility". [3] ITU-T Recommendation X.681 (1994): "Information technology-Abstract Syntax Notation One (ASN.1): Information object specification". [4] ITU-T Recommendation X.681 Amendment 1 (1994): "Information technology-Abstract Syntax Notation One (ASN.1): Rules of extensibility ". [5] ITU-T Recommendation X.682 (1994): "Information technology-Abstract Syntax Notation One (ASN.1): constraint specification". [6] ITU-T Recommendation X.683 (1994): "Information technology-Abstract Syntax Notation One (ASN.1): Parameterisation of ASN.1 specifications". [7] ITU-T Recommendation Z.100 (1993): "CCITT Specification and Description Language (SDL)". [8] ITU-T Recommendation Z.105 (1994): "SDL combined with ASN.1 (SDL/ASN.1)". [9] CCITT Recommendation X.208 (1990) : "Specification of the Abstract Syntax Notation One (ASN.1) ". [10] TR 101 101 (1997) "Methods for Testing and Specification (MTS); TTCN interim version including ASN.1 1994 support [ISO/IEC 9646-3] (Second Edition Mock-up for JTC1/SC21 Review)". [11] ISO/IEC 10646-1 (1993): "Information technology, - Multiple-Octet Coded Character Set (UCS) - Part 1: Architecture and Basic Multilingual Plane". [12] ETS 300 414 (1995): "Methods for Testing and Specification (MTS); Use of SDL in European Telecommunications Standards; Rules for testability and facilitating validation". [13] ETR 60 (1995) "Signalling Protocols and Switching (SPS);Guidelines for using Abstract Syntax Notation one (ASN.1) in telecommunication application protocols". ETSI TR 101 295 V1.1.1 (1998-09) 6 |
e182c81fd1e4596e5b513a391752528a | 101 295 | 3 Definitions and abbreviations | For the purposes of the present document, the following definitions apply: ASN.1 94: ASN.1 as defined in the 1994 ITU-T Recommendations X.680 [1], X.680 Amendment 1 [2], X.681 [3], X.681 Amendment 1 [4], X.682 [5] and X.683 [6]. ASN.1 90: ASN.1 as defined in the 1990 ITU-T Recommendations X.208 [9] ASN.1 X.680: ASN.1 core language as defined in the 1994 ITU-T Recommendations X.680 [1], but omitting all features of ASN.1 94 defined in X.680 Amendment 1 [2], X.681 [3], X.681 Amendment 1 [4], X.682 [5] and X.683 [6]. |
e182c81fd1e4596e5b513a391752528a | 101 295 | 3.2 Abbreviations | For the purposes of the present document, the following abbreviations apply: ASN.1 Abstract Syntax Notation 1 BER Basic Encoding Rules PER Packed Encoding Rules SDL Specification and Description Language TTCN Tree and Tabular Combined Notation |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4 Transformation of ASN.1 94 material to ASN.1 X.680 | |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.1 Introduction | This clause defines a set of generic transformation rules to convert ASN.1 94 modules to "pure" X.680 [1] constructs. Each sub-clause addresses a particular ASN.1 94 feature which is not supported in X.680 [1]. For each feature the transformation rules together with any limitations effecting the validity of the conversions are described. Each transformation rule is illustrated with one or more examples. The examples use underlining to identify the elements that must be changed. To apply these transformation rules every instance of the specified features must be identified within the ASN.1 94 module and the corresponding transformation rules, associated with that feature, applied. |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.2 Extensibility | |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.2.1 Description | Extensibility provides a mechanism for future compatibility by defining a syntax which will accept elements not defined in that syntax. ASN.1 94 allows extensibility to be specified within a syntax definition. The extensibility can either be specified explicitly using the extension marker "..." or globally across an ASN.1 module by addition of an optional field in the module header. The extension marker can be placed in the definition of ENUMERATED TYPE, SEQUENCE, SET and CHOICE. The effect of the extension marker is to disable error generation when the received element does not match the specified syntax of the associated type. If extensibility is activated by use of the optional module header field all definition involving the relevant types will be extensible within that module. No transformation rules can preserve the full semantics of extensibility. The specified transformation rules can only generate a syntax that will provide backwards compatibility for the extension series up to and including the ASN.1 94 version being converted. All forwards compatibility is lost apart from that explicitly added in rule 3. ETSI TR 101 295 V1.1.1 (1998-09) 7 |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.2.2 Transformation rules | Rule 1: If present, remove extensibility field from ASN.1 module header. Example: 1 Example-Module DEFINITIONS AUTOMATIC TAGS EXTENSIBILITY IMPLIED ::= BEGIN ModuleBody END Transforms to: Example-Module DEFINITIONS AUTOMATIC TAGS ::= BEGIN ModuleBody END Rule 2: Remove all extension markers. Any types defined after the extension marker in SET or SEQUENCE definitions should be made OPTIONAL Example:2 MyType ::= SEQUENCE { a INTEGER, ..., b BOOLEAN } transforms to: MyType ::= SEQUENCE { a INTEGER, b BOOLEAN OPTIONAL } Rule 3: Add known future components as optional (in SEQUENCE, SET and CHOICE). ETSI TR 101 295 V1.1.1 (1998-09) 8 Add known future enumeration items (in ENUMERATED) Example 3: If it is already known that the next version of the protocol will add an OCTET STRING field to MyType, defined in Example 2, update it as follows: MyType ::= SEQUENCE { a INTEGER, b BOOLEAN OPTIONAL, c OCTETSTRING OPTIONAL } |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.2.3 Transformation limitations | The transformation rules do not retain any forward compatibility provided by the extension marker in the original ASN.1 94 module. These transformations also require consideration of any associated transfer syntax. For some encoding rules, most notably PER, the extension marker is visible in the transmitted bytes. In such a case these transformation rules cannot be validly applied. The resultant ASN.1 X.680 [1] definitions would be incompatible with the original ASN.1 94 module. It should be noted that this limitation is only applicable when firstly we are dealing with transmitted bytes (conformance testing, code generation) and secondly when we are using an encoding rule where the extension marker is visible in the transfer syntax. NOTE: It follows that for any tool which cannot support extension markers the transfer syntax of certain ASN.1 94 systems might be impossible to reproduce. The transformation rules provide no solution for extensibility markers used within information object set definitions. |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.3 Parameterization | |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.3.1 Description | ASN.1 94 supports value parameterization for value notation and value parameterization in type notation for definition of constraints. ASN.1 94 also includes the concept of generic type parameterization. For example, consider the following definition: MESSAGE { PDUType } ::= SEQUENCE { asp ASPType, pdu PDUType } This defines the parameterized type MESSAGE{}. Within the body of the protocol this parameterized type can be used to define further types. For example: SetupMessage ::= MESSAGE { SetupPDU } ETSI TR 101 295 V1.1.1 (1998-09) 9 |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.3.2 Transformation rules | Rule 2: Expand out the parameterized types and values. Example 4: -- Parameterized value in value notation genericGreeting{ IA5String : name} IA5String ::= {"Hello", name} firstString IA5String ::= genericGreeting{ "World"} -- Parameterized value in type notation Message1{ INTEGER:maxSize, INTEGER:minSize} ::= SEQUENCE { asp INTEGER, pdu OCTET STRING (SIZE (minSize..maxSize)) } ExampleMsg ::= Message1{10, 40} -- Parameterized type definition Message2{ PDUType } ::= SEQUENCE { asp ASPType, pdu PDUType } SetupMessage ::= Message2{ SetupPDU } transforms to: -- Transformed Parameterized value in value notation firstString IA5String ::= "HelloWorld" -- Transformed Parameterized value in type notation ExampleMsg ::= SEQUENCE { ETSI TR 101 295 V1.1.1 (1998-09) 10 asp INTEGER, pdu OCTET STRING (SIZE (10..40)) } -- Transformed Parameterized type definition SetupMessage ::= SEQUENCE { asp ASPType, pdu SetupPDU } |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.3.3 Transformation limitations | When information objects classes, objects and object sets are used in parameterization, the transformation rules for information objects must be applied to these definitions before the parameterization is expanded out. |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.4 Information objects | |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.4.1 Description | Information Objects are the macro replacement mechanism defined in ASN.1 94. In principle information objects are a form of generic table which allows the association of specific sets of field values or types. The greatest single advantage of Information objects is they are machine processable. In ASN.1 94 some of the defined types within the language are defined in terms of information objects (these types and classes are INSTANCE-OF, TYPE-IDENTIFIER and ABSTRACT-SYNTAX). In principle the transformation rules must replace information extracted from information objects or class, i.e. corresponding to notation ObjectClassFieldType, TypeFromObject, ValueSetFromObjects, ObjectClassFieldValue, ValueFromObject by the information itself in the abstract syntax definitions. |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.4.2 Transformation rules | Rule 5: Replace use of "InstanceOfType" notation by the associated sequence. Example 5: ACCESS-CONTROL-CLASS ::= TYPE-IDENTIFIER AccessControl ::= INSTANCE OF ACCESS-CONTROL-CLASS ({PossibleTypes}) transforms to: AccessControl ::= [UNIVERSAL 8] IMPLICIT SEQUENCE ETSI TR 101 295 V1.1.1 (1998-09) 11 { type-id ACCESS-COTROL-CLASS.&id ({PossibleTypes}), value [0] ACCESS-CONTROL-CLASS ({PossibleTypes}{@.type-id}) } Rule 6: Remove any Component relation constraints in type declarations Example 6: Given the following Information object definition MESSAGE ::= CLASS { &msgCode INTEGER UNIQUE, &msgLength INTEGER, &MsgDataType OPTIONAL } WITH SYNTAX { CODE &msgCode, LENGTH &msgLength, [DATA TYPE &MsgDataType] } used to define the object set ConnectPhaseMsgs: ConnectPhaseMsgs MESSAGE ::= { setup | setupAck | release | relAck } setup MESSAGE ::= { CODE 1 LENGTH 12 ETSI TR 101 295 V1.1.1 (1998-09) 12 DATA TYPE OCTET STRING } setupAck MESSAGE ::= { CODE 2 LENGTH 5 DATA TYPE INTEGER } release MESSAGE ::= { CODE 3 LENGTH 1 } relAck MESSAGE ::= { CODE 4 LENGTH 1 } The associated type definition: ConnectPhasePDU ::= SEQUENCE { id MESSAGE.&msgCode ({ConnectPhaseMsgs}), size MESSAGE.&msgLength ({ConnectPhaseMsgs } {@id}), data MESSAGE.&MsgDataType ({ConnectPhaseMsgs } {@id}) OPTIONAL } transforms to: ConnectPhasePDU ::= SEQUENCE ETSI TR 101 295 V1.1.1 (1998-09) 13 { id MESSAGE.&msgCode ({ConnectPhaseMsgs}), size MESSAGE.&msgLength ({ConnectPhaseMsgs }), data MESSAGE.&MsgDataType ({ConnectPhaseMsgs }) OPTIONAL } Rule 7: Replace references to object set value fields in type definitions by using generic type plus subtyping or by defining a new type to represent the possible value set. The required generic type and possible value set must be extracted from the information object set. Example 7: Given the information object set and associated ConnectPDU type definition from Example 6. ConnectPhasePDU ::= SEQUENCE { id MESSAGE.&msgCode ({ConnectPhaseMsgs}), size MESSAGE.&msgLength ({ConnectPhaseMsgs }), data MESSAGE.&MsgDataType ({ConnectPhaseMsgs }) OPTIONAL } transforms to: ConnectPhasePDU ::= SEQUENCE { id INTEGER (1..4), size INTEGER (1 | 5 | 12), data MESSAGE.&MsgDataType ({ConnectPhaseMsgs }) OPTIONAL } Or the cleaner solution declaring new types, transforms to: ETSI TR 101 295 V1.1.1 (1998-09) 14 MsgCodes ::= INTEGER(1..4) MsgSizes ::= INTEGER(1 | 5 | 12) ConnectPhasePDU ::= SEQUENCE { id MsgCodes, size MsgSizes, data MESSAGE.&MsgDataType ({ConnectPhaseMsgs }) OPTIONAL } Rule 8: Replace references to information object type fields in type definitions by transforming into CHOICE construct. Example 8: Given the ConnectPDU type definition from the end of EXAMPLE 7. ConnectPhasePDU ::= SEQUENCE { id MsgCodes, size MsgSizes, data MESSAGE.&MsgDataType ({ConnectPhaseMsgs }) OPTIONAL } transforms to: ConnectPhasePDU ::= SEQUENCE { id INTEGER (1..4), size INTEGER (1 | 5 | 12), data CHOICE { setupBody OCTET STRING, setupAckBody INTEGER} OPTIONAL } Or the cleaner solution declaring a new type: MsgBody ::= CHOICE { ETSI TR 101 295 V1.1.1 (1998-09) 15 setupBody OCTET STRING, setupAckBody INTEGER } ConnectPhasePDU ::= SEQUENCE { id MsgCodes, size MsgSizes, data MsgBody OPTIONAL } Rule 9: Remove or change to ASN.1 comments all definition of classes, information objects and object sets. Example 9: Considering Example 6 all the following definitions should be deleted or converted into comments: MESSAGE ::= CLASS { &msgCode INTEGER UNIQUE, &msgLength INTEGER, &MsgDataType OPTIONAL } WITH SYNTAX { CODE &msgCode, LENGTH &msgLength, [DATA TYPE &MsgDataType] } setup MESSAGE ::= { CODE 1 LENGTH 12 DATA TYPE OCTET STRING } ETSI TR 101 295 V1.1.1 (1998-09) 16 setupAck MESSAGE ::= { CODE 2 LENGTH 5 DATA TYPE INTEGER } release MESSAGE ::= { CODE 3 LENGTH 1 } relAck MESSAGE ::= { CODE 4 LENGTH 1 } ConnectPhaseMsgs MESSAGE ::= { setup | setupAck | release | relAck } |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.4.3 Transformation limitations | The validity of transformation rule 7 which involves converting a reference to an information object set into a type containing a CHOICE is dependant on the transfer syntax. If the required encoding rules make the CHOICE visible in the transfer syntax (PER for example) this transformation is invalid (changes the bits transmitted on the line). For SDL applications where the transfer syntax is not an issue and for all application areas using a transfer syntax where the CHOICE is not visible (BER for example) transformation rule 7 is still valid. The second limitation is these transformation rules provide no mechanism for handling situations where it is impossible to construct an associated CHOICE type. For example if we have the type definition: ConnectPhasePDU ::= SEQUENCE { id MESSAGE.&msgCode ETSI TR 101 295 V1.1.1 (1998-09) 17 ({ConnectPhaseMsgs}), size MESSAGE.&msgLength ({ConnectPhaseMsgs } {@id}), data MESSAGE.&MsgDataType OPTIONAL } The data field is unconstrained, it can be of any type. In this situation it is impossible to implement transformation rule 7 and convert this field to an associated CHOICE type. The transformation rules presented in this clause cannot reproduce the full semantics of the information objects they replace. The transformation rules cannot preserve component relation constraints. These constraints provide the ability to constrain a type or value with reference to a different field within an information object set. For example if we consider EXAMPLE 6 in the ConnectPhasePDU type the size field has the component relational constraint {@id}. This means the size field is constrained to the possible values defined in the object set ConnectPhaseMsgs which have the correct id field value. |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.5 User defined constraints | |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.5.1 Description | This feature is used to express constraints which are too complex to represent using the normal ASN.1 constraints mechanisms. The ASN.1 94 language does not fully specify how to process these constraints and in effect this feature just provides a special form of ASN.1 comment in which the required constraint mechanism is described in text. User defined constraints need to be removed or converted into an ASN.1 comment. |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.5.2 Transformation rules | Rule 10: Remove user defined constraints or convert to ASN.1 comment. Example 10: ENCRYPTED {ToBeEnciphered} ::= BIT STRING (CONSTRAINED BY {-- must be the result of the encipher of some BER-encoded value of -- ToBeEnciphered} ! Error : securityViolation) transforms to: ENCRYPTED ::= BIT STRING or ENCRYPTED {ToBeEnciphered} ::= BIT STRING -- (CONSTRAINED BY -- -- { must be the result of the encipher of some BER-encoded value of ToBeEnciphered} -- -- ! Error : securityViolation) -- ETSI TR 101 295 V1.1.1 (1998-09) 18 |
e182c81fd1e4596e5b513a391752528a | 101 295 | 4.5.3 Transformation limitations | Since user defined constraints can be regarded as a special form of ASN.1 comment this transformation is completely transparent. ETSI TR 101 295 V1.1.1 (1998-09) 19 Annex A (informative): Additional rules relative to the use of ASN.1 94 in conjunction with SDL A.1 Identifiers Case sensitivity is not supported by Z.100 [7] and Z.105 [8]. This restriction implies that introducing two types with the same name (apart from case sensitivity) is an error. However, it is allowed to have the same name if they are of different entity classes. Entity classes are for example, type names, value names and identifiers. Rule A11: Rename the ASN.1 entities so that two entities of the same class shall not be identical when put in lower case. Example A1: TypeA ::= OCTET STRING (3) Typea ::= SEQUENCE {a INTEGER, b BOOLEAN } can be replaced by: AType ::= OCTET STRING (3) Typea ::= SEQUENCE {a INTEGER, b BOOLEAN } The use of the same identifier for multiple named numbers or multiple named bits of different types in the same scope shall be avoided. The motivation is that named numbers and named bits are mapped onto SDL literals and SDL integer synonyms respectively. Using the same identifier twice would result in illegal SDL (redefinition of the same synonym or same literal). Double use of the same identifier in different enumerated types, or in an enumerated type and in a named integer or named bit is allowed, because the identifiers in enumerated types are not mapped on integer synonyms. Rule A12: Rename the numbers of bits so that the identifiers for named numbers or named bits of different types in the same scope shall not be identical. Example A2: Int1 ::= INTEGER { a (0) } Int2 ::= INTEGER { a (1) } transforms to: Int1 ::= INTEGER { a1 (0) } Int2 ::= INTEGER { a2 (1) } The OBJECT IDENTIFIER component values that are assigned by ITU-T, ISO, or both, are not defined in the package called Predefined. ETSI TR 101 295 V1.1.1 (1998-09) 20 Rule A13: Define and import an SDL package containing the definitions of components of the OBJECT IDENTIFIERS used in the ASN.1 Example A3: In order to use : {ccitt recommendation q 1228 } the component values CCITT, recommendation, and q have to be defined in a user defined package. ETSI TR 101 295 V1.1.1 (1998-09) 21 Annex B (informative): Additional rules relative to the use of ASN.1 94 in conjunction with TTCN B.1 Automatic tagging B.1.1 Description ASN.1 94 introduces the feature of AUTOMATIC tagging. This provides a new tagging mode in addition to the existing IMPLICIT and EXPLICIT. When AUTOMATIC tagging is selected the system will automatically insert any necessary tags within the associated module without the need for user intervention (N.B. the user still has the choice to override the AUTOMATIC mechanism for specific constructs by explicitly defining tags). AUTOMATIC tags is selected from the ASN.1 module header. Since TTCN only allows ASN.1 type definitions not module definitions there is no current mechanism for selecting the tagging regime within TTCN (it is by default EXPLICIT). B.1.2 Transformation rules These transformation rules need only be applied if the source ASN.1 94 module has the tagging type set to AUTOMATIC in the module header. Rule B11: Expand out COMPONENTS OF for all SEQUENCE constructs which contain no tagged type. Example B1: TypeA ::= SEQUENCE { alpha INTEGER, beta BOOLEAN } -- SEQUENCE construct with tagged type TypeB ::= SEQUENCE { cappa INTEGER, delta [1]BOOLEAN, COMPONENTS OF TypeA } -- SEQUENCE construct without tagged type TypeC ::= SEQUENCE { ETSI TR 101 295 V1.1.1 (1998-09) 22 cappa INTEGER, delta BOOLEAN, COMPONENTS OF TypeA } transforms to : -- SEQUENCE construct with tagged type (no change) TypeB ::= SEQUENCE { cappa INTEGER, delta [1]BOOLEAN, COMPONENTS OF TypeA } -- SEQUENCE construct without tagged type COMPONENTS OF expanded out TypeC ::= SEQUENCE { cappa INTEGER, delta BOOLEAN, alpha INTEGER, beta BOOLEAN } Rule B12: Manually add tag type for all SEQUENCE constructs which contain no tagged type (or contain tagged type due to transformation rule B11). Example B2: -- SEQUENCE construct without tagged type TypeC ::= SEQUENCE { cappa INTEGER, delta BOOLEAN, ETSI TR 101 295 V1.1.1 (1998-09) 23 alpha INTEGER, beta BOOLEAN } transforms to : TypeC ::= SEQUENCE { cappa [0] IMPLICIT INTEGER, delta [1] IMPLICIT BOOLEAN, alpha [2] IMPLICIT INTEGER, beta [3] IMPLICIT BOOLEAN } Rule B13: Manually add tag type for all SET constructs which contain no existing tagged type. Example B3: -- SET construct without tagged type TypeD ::= SET { cappa INTEGER, delta BOOLEAN, alpha INTEGER, beta BOOLEAN } transforms to : TypeD ::= SET { cappa [0] IMPLICIT INTEGER, delta [1] IMPLICIT BOOLEAN, ETSI TR 101 295 V1.1.1 (1998-09) 24 alpha [2] IMPLICIT INTEGER, beta [3] IMPLICIT BOOLEAN } Rule B14: Manually add tag types for all CHOICE constructs which contain no existing tagged type. EXAMPLE B4: -- CHOICE construct without tagged type TypeE ::= CHOICE { cappa INTEGER, delta BOOLEAN } transforms to : TypeE ::= CHOICE { cappa [0] IMPLICIT INTEGER, delta [1] IMPLICIT BOOLEAN } B.1.3 Transformation limitations If the type within the respective construct is a CHOICE type, open type or a DummyReference, AUTOMATIC tagging inserts an EXPLICIT tag type for this element. Annex C (informative): Additional feature support required to extend tools from ASN.1 90 to ASN.1 X.680 This annex lists the differences between ASN.1 90 and ASN.1 X.680. This list can be used as a check list for upgrading ASN.1 based tools. This appendix is composed of two subclauses: a first one list the features which have been removed or changed. A second one gives the features which have been incorporated in addition. ETSI TR 101 295 V1.1.1 (1998-09) 25 C.1 Alterations C.1.1 Removal of Macros In ASN.1 90 the macro capability allowed the user to extend the notation by providing macros. This capability had the disadvantage that it was not machine processable (redefinition of grammar on the fly) and thus was not fully supported by tools. This capability has been removed in X.680 [1] and replaced by the information objects and the parameterization capability defined respectively in X.681[3] and X.683 [6]. C.1.2 Removal of ANY and ANY DEFINED BY The normal use of the any type defined in ASN.1 90 was to leave a "hole" in a specification which would be filled in by some other specification. In X.680 [1] the any type has been superseded by the ability to specify information object classes and then to refer to the fields of information object classes from within type definitions (X.681 [3]). Though described in X.680 [1], the notations AnyType and AnyValue should not be supported by tools. C.1.3 Local identifiers Contrary to ASN.1 90, in X.680 [1] identifiers are mandatory in NamedTypes and NamedValues. The NamedType notation which was defined in ASN.1 90 as NamedType ::= identifier Type | Type | SelectionType has been changed to NamedType ::= identifier Type | SelectionType In a same way the Named value notation has been changed from NamedValue ::= identifier Value | Value to NamedValue ::= identifier Value C.1.4 Choice Value syntax In order to remove some ambiguities, the ChoiceValue now contains a colon. The ChoiceValue notation which was defined in ASN.1 90 as ChoiceValue ::= NamedValue has been changed to ChoiceValue ::= identifier ":" Value C.1.5 External The associated type for the EXTERNAL type has been changed from: EXTERNAL = [UNIVERSAL 8] IMPLICIT SEQUENCE { direct-reference OBJECT IDENTIFIER OPTIONAL, indirect-reference INTEGER OPTIONAL, data-value-descriptor ObjectDescriptor OPTIONAL, encoding CHOICE ETSI TR 101 295 V1.1.1 (1998-09) 26 {single-ASN1-type [0] ANY, octet-aligned [1] IMPLICIT OCTET STRING, arbitrary [2] IMPLICIT BIT STRING } } to: SEQUENCE { identification CHOICE { syntaxes SEQUENCE { abstract OBJECT IDENTIFIER, transfer OBJECT IDENTIFIER } -- Abstract and transfer syntax object identifiers --, syntax OBJECT IDENTIFIER -- A single object identifier for identification of the class and encoding --, presentation-context-id INTEGER -- (Applicable only to OSI environments) -- The negotiated presentation context identifies the class of the value and its encoding --, context-negotiation SEQUENCE { presentation-context-id INTEGER transfer-syntax OBJECT IDENTIFIER } -- (Applicable only to OSI environments) -- Context-negotiation in progress for a context to identify the class of the value -- and its encoding --, transfer-syntax OBJECT IDENTIFIER -- The class of the value (for example, specification that it is the value of an ASN.1 type) -- is fixed by the application designer (and hence known to both sender and receiver). This -- case is provided primarily to support selective-field-encryption (or other encoding -- transformations) of an ASN.1 type --, fixed NULL -- The data value is the value of a fixed ASN.1 type (and hence known to both sender -- and receiver) -- }, data-value-descriptor ObjectDescriptor OPTIONAL -- This provides human-readable identification of the class of the value --, data-value CHOICE { notation ABSTRACT-SYNTAX.&Type ETSI TR 101 295 V1.1.1 (1998-09) 27 -- This type notation is defined in X.681[3] and has a value -- notation which is any ASN.1 type definition, followed by a colon and the value notation -- for that type. This choice alternative is provided to enable the specification using -- human-friendly notation of the data values that are values of an ASN.1 type. --, encoded BIT STRING -- This choice alternative is provided to enable the specification of data values that are not -- values of a single ASN.1 type. -- } } ( WITH COMPONENTS { ... , identification (WITH COMPONENTS { ... , syntaxes ABSENT, transfer-syntax ABSENT, fixed ABSENT } ) } ) C.2 Additions C.2.1 Automatic tagging The AUTOMATIC TAGS keyword has been added to the TagDefault notation. It allows the definition of a module without insertion of tags in the module body. TagDefault ::= EXPLICIT TAGS | IMPLICIT TAGS | empty has been replaced by: TagDefault ::= EXPLICIT TAGS | IMPLICIT TAGS | AUTOMATIC TAGS | empty ETSI TR 101 295 V1.1.1 (1998-09) 28 C.2.2 Embedded PDV The EmbeddedPDVType, a superset of EXTERNAL with more efficient encoding, has been added to the BuiltinType notation. Similarly the EmbeddePDVValue has been added to the BuiltinValue notation. The BuiltinType notation is now: BuiltinType ::= ... EmbeddedPDVType | ... EmbeddedPDVType ::= EMBEDDED PDV The BuiltinValue notation is now: BuiltinValue ::= ... EmbeddedPDVValue | ... EmbeddedPDVValue ::= SequenceValue C.2.3 String types Three new string types has been added: UniversalString, BMPString and CHARACTER STRING. The first two type are intended to carry characters defined in ISO 10646-1 [11]. CHARACTER STRING is an unrestricted string type intended to model any string which cannot be represented with any of the other existing ASN.1 string types. C.2.4 Exception specification The exception specification indicates special handling in the event of an exceptional condition. Subtype has been replaced by Constrainedtype itself defined as: ConstrainedType ::= Type Constraint | TypeWithConsraint Constraint ::= "(" ConstraintSpec ExceptionSpec ")" ExceptionSpec ::= "!" ExceptionIdentification | empty ExceptionIdentification ::= SignedNumber | DefinedValue | Type ":" Value C.2.5 New subtype operators The ASN.1 90 SubType notation has been replaced by the ConstrainedType notation enhancing the possibilities of subtyping with new operators: UNION, INTERSECTION, EXCLUSION. ETSI TR 101 295 V1.1.1 (1998-09) 29 History Document history V1.1.1 September 1998 Publication ISBN 2-7437-2379-3 Dépôt légal : Septembre 1998 |
890633305f5cc56e514b089b1797c1f3 | 101 233 | 1 Scope | The present document is intended as a companion document to ETS 300 706 [1] and ETS 300 708 [2], covering the data format and transmission via Teletext. It is primarily aimed broadcasters and telecommunications network operators with the intention that there is a consistent approach to the positioning of services within the Vertical Blanking Interval (VBI) of 625/50 Phase Alternation Line (PAL) derived services in Europe. The main area of interest is in the VBI as received at home, and thus the effects of all the telecommunication systems that are used to convey the signal are taken into account. Thus as there are many options available to all the parties involved in creating the total system, some common understanding of the concepts involved is required as well as formal agreements between parties for the use of the VBI. |
890633305f5cc56e514b089b1797c1f3 | 101 233 | 2 References | References may be made to: a) specific versions of publications (identified by date of publication, edition number, version number, etc.), in which case, subsequent revisions to the referenced document do not apply; or b) all versions up to and including the identified version (identified by "up to and including" before the version identity); or c) all versions subsequent to and including the identified version (identified by "onwards" following the version identity); or d) publications without mention of a specific version, in which case the latest version applies. A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same number. [1] ETS 300 706: "Enhanced Teletext specification". [2] ETS 300 708: "Television systems; Data transmission within Teletext". [3] ETS 300 231: "Television systems; Specification of the domestic video Programme Delivery Control system (PDC)". [4] ETR 287: "Television systems; Code of practice for enhanced Teletext". [5] ETR 288: "Television systems; Code of practice for an Electronic Programme Guide (EPG)". [6] ETS 300 294: "Television systems; 625-line television Wide Screen Signalling (WSS)". [7] ETS 300 732: "Television systems; Enhanced 625-line PAL/SECAM television; Ghost Cancellation Reference (GCR) signals". [8] ITU-R Recommendation 473: "Insertion test signals in the field blanking interval of monochrome and colour television signals". [9] ITU-R Recommendation 567: "Test signals for Television Systems". [10] EBU Recommendation R26-1981: "The use of Insertion -reference signals(IRS) in television production installations". TR 101 233 V1.1.1 (1998-02) 6 |
890633305f5cc56e514b089b1797c1f3 | 101 233 | 3 Definitions and abbreviations | |
890633305f5cc56e514b089b1797c1f3 | 101 233 | 3.1 Definitions | For the purposes of the present document, the following definitions apply: Data stream: A continuous sequence of related data. Decoder: A Teletext decoder collects and decodes the transmitted Teletext data. It processes and stores the data and under user control selects the information for display. Decoders can differ in their storage capacity and display capability. Filler packets: Dummy packets inserted onto otherwise unused VBI lines which exists as a result of obeying the 20 ms page clearing rule. Level 1, 1.5, 2.5, 3.5: Teletext presentation levels. 20 ms page clearing rule: This rule defines the minimum interval between the transmission of the page header (row 0) of a Teletext page and the transmission of the remaining packets. It is essential for some existing Teletext decoders to give them time to erase the old page from memory. Level 2.5 (and above) decoders can operate without such a delay being necessary. This is referred to as the 20 ms rule in ETS 300 707 [1]. |
890633305f5cc56e514b089b1797c1f3 | 101 233 | 3.2 Abbreviations | For the purposes of the present document, the following abbreviations apply: CNI Country and Network Identification code CVBS Composite Video, Blanking and Synchs EACEM European Association of Consumer Electronic Manufacturers EPG Electronic Programme Guide FBI Field Blanking Interval GCR Ghost Cancel Reference ITS Insertion Test Signal(s) LCI Label Channel Indentifier NTSC National Television Standards Committee (TV standard) PAL Phase Alternation Line (colour TV system) PDC Programme Delivery Control SECAM SequentiellE Couleur Avec Mémoire (French colour TV system) TV TeleVision UTC Universal Time Co-ordinated VBI Vertical Blanking Interval VCR Video Cassette Recorder VITC Vertical Interval Time-Code VPS Video Programming System WSS Wide Screen Signalling TR 101 233 V1.1.1 (1998-02) 7 |
890633305f5cc56e514b089b1797c1f3 | 101 233 | 4 Generalities | The television Vertical Blanking Interval (VBI), also known as the Field Blanking Interval (FBI) consists of the TV lines 623 to 22 in field one and 311 to 335 in field two. By convention, there is an association between a line in field one and the line in field two 313 lines later. So the complement of line 6 is 319 and the line pair of line 6 and 319 is referred to as 6/319. 6 7 8 9 1 0 1 1 1 2 13 1 4 1 5 16 1 7 1 8 19 2 0 21 23 2 4 6 22 3 10 p o ssible T elete xt D ata-L in e s Multip lexed M o de fie ld -blan kin g Int e rval (25 lines) 318 3 19 320 32 1 32 2 32 3 32 4 3 2 5 32 6 3 2 7 328 32 9 33 0 33 1 3 3 2 3 33 3 34 3 3 5 2 2 ( VBI ) Figure 1: Usable TV lines, when multiplexed with a CVBS signal ETS 300 706 [1] permits the operation of Teletext signals on lines 6/319 to 22/335 plus line 318. Broadcasters, regulatory authorities and the common carriers of information such as public telecommunications operators, cable and satellite operators may use lines in this range for a variety of purposes such as: a) test signals; b) quiet lines; c) encryption systems; d) Teletext based signals; e) non-Teletext based data broadcasting; f) closed caption text services. The present document indicates where these signals may be located and points out the basis on which services are allocated to VBI lines. This may vary from country to country. |
890633305f5cc56e514b089b1797c1f3 | 101 233 | 5 Signals | |
890633305f5cc56e514b089b1797c1f3 | 101 233 | 5.1 Signals whose line number is specified |
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