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da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 4 Introduction | Digital Audio Broadcasting DAB [1] provides the text feature Dynamic Label (DL) which allows the service provider to send text messages with information such as track playing, now/next, news headlines, weather, sport results, etc. To serve all the different interests of listeners, the service provider has to send DL me... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 5 DL Plus objects | |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 5.0 Introduction | DL Plus objects are created in receivers from DL messages and associated DL Plus tags. Therefore the DL Plus objects inherit some basic properties from the DL messages they are based on: • The text of DL Plus objects shall be contained within a single DL message, and so has a maximum text length determined by the limit... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 5.1 Content types | Each DL Plus object is assigned a content type chosen by the service provider from those available. 64 content types are currently defined, see table A.1. These content types correspond exactly to those defined for the FM-RDS RT+ feature. A further 64 content types are reserved for future addition. The user can select ... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 5.2 Linking of DL Plus objects | |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 5.2.0 Introduction | In general, DL Plus objects carry information that is meaningful in itself, without knowledge of information provided by other DL Plus objects (except for DL Plus objects in category Descriptor). DL Plus provides mechanisms to combine the information of two or more DL Plus objects. There are three structuring methods: ... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 5.2.1 Aggregating DL Plus objects (category Item) | Whilst a programme item is in progress, several DL messages may be sent and some of them will signal the creation of various DL Plus objects with content types in the Item category (with information about title, artist, composer, etc.) and all referring to the same programme item. These may be aggregated to give a full... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 5.2.2 Compiling DL Plus objects into tables | DL Plus objects can be compiled to a table, provided: • they all have the same content type from categories Info, Programme or Interactivity; and • the text of the objects contains redundant spaces. The term "redundant spaces" is defined as two or more space/blank characters together within the text of the DL message. ... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 5.2.3 Linking a Descriptor object to another DL Plus object | A Descriptor object is meaningful only in combination with another DL Plus object and it provides further detail of the other object. A DL Plus object (parent object) and its Descriptor objects shall be transmitted in the same DL message; therefore a DL message may carry one parent object with three linked Descriptor o... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 5.3 Life time, updating and deletion | |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 5.3.0 Introduction | DL Plus allows a receiver to store at least as many up-to-date DL Plus objects as there are content types defined. If the receiver supports the compilation of objects into tables, it will store multiple objects with the same content type. The receiver shall respect the life time of the multiple objects. The object star... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 5.3.1 Updating objects | Objects are updated by transmitting a new object with the same content type as an existing object. When a new DL Plus object is received, it replaces the object stored under the same content type. In the case of tables, the keyword qualifies which object is to be replaced. |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 5.3.2 Deleting objects | Objects are deleted by transmitting a "delete" object (see clause 6.2) with the same content type as an existing object. When a "delete" object is received, it removes the object stored under the same content type. In the case of tables, the complete table is removed. It is not possible to delete individual table entri... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 6 DL Plus tags | |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 6.0 Introduction | The receiver constructs the DL Plus objects from the received DL message and DL Plus tags (see figure 1). The first character of the DL message is character 0. DL messages may contain up to 128 characters, depending on the indicated character set (see ETSI EN 300 401 [1], clause 7.4.5.2). The coding of a DL Plus tag is... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 6.1 Creating a dummy object | DL Plus tags may be used to create dummy objects, either to improve the timing accuracy of the item toggle bit and item running bit (see clause 5.2.1), to inform receivers that DL Plus is still active when there are no DL Plus objects associated with the current DL message, or for compatibility with RT+. To create a du... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 6.2 Creating a delete object | To create a delete object, the content type is set to the required value, the start marker specifies a blank character and the length marker is set to 0. Any blank character may be specified. EXAMPLE: Hotline: 0123456677 0----0----1----1----2----2----3----3----4----4----5----5----6--- 0----5----0----5----0----5----0---... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 7 Command structure | |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 7.1 Transport of DL Plus commands | DL commands are transported using the same mechanism as that for DL messages, see ETSI EN 300 401 [1], clause 7.4.5.2. When the Command field = 0 0 1 0 (DL Plus command), Field 2, Field 3 and the DL Command field shall be used as follows: Figure 6: Structure of Field 2 for DL Plus The following definitions apply: • Fie... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 7.2 DL Plus commands: general structure | The presence of DL Plus is signalled implicitly by the occurrence of DL Plus commands in the same X-PAD data stream as the DL messages (application types 2 and 3) i.e. the presence of DL commands where the Command field contains the value "0 0 1 0". Figure 7 shows the general structure of the DL Plus command. Figure 7:... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 7.3 The DL Plus tags command | DL tags are conveyed in the DL Plus tags command. It may be segmented in several DL Plus command fields. A DL Plus tags command can transport up to 4 DL Plus tags that refer to the same DL message. Figure 8 shows the structure of the DL Plus tags command. Figure 8: Structure of the DL Plus tags command The following de... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 7.4 Transmission sequence | The complete DL message shall be transmitted before the related DL Plus command(s) are transmitted. The L (Link) bit of the DL Plus tags command shall be set to the same value as the T (Toggle) bit of the related DL message. The DL message and DL Plus command(s) may be repeated to guard against transmission errors, but... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 8 Receiver behaviour | |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 8.0 Introduction | DL Plus provides an enhanced way to view DL messages. This allows a great variety of receiver terminals with different concepts, depending on the user expectations and requirements, the terminal hardware and software resources. Some DL Plus use cases are given in annex B. |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 8.1 Basic requirements | Receivers shall be capable of processing both the DL messages and the DL Plus tags that are carried in the DL Plus commands. When a receiver is tuned to a service, it shall start by processing the DL messages only. As soon as a DL Plus command is received it shall start processing DL messages and DL Plus commands to cr... |
da23acec8b7cb8465231a9f5f80bec0a | 102 980 | 8.2 History | A simple receiver will only handle the current DL Plus objects, e.g. it displays the current news headline. A more advanced receiver may provide a history function, so that it can offer the information carried in objects previously received, so a user could recall the last headlines received. A receiver with such a his... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 1 Scope | De-jitter buffers and echo cancellers have a major effect on voice and data transmission quality in telecommunication networks. They affect the three service categories of PSTN/ISDN voice, voiceband data (due to PSTN modem and fax calls), and ISDN circuit mode data. Since the requirements for the settings of de-jitter ... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 2 References | |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 2.1 Normative references | References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the referenced document (including any amendments) applies. Referenced documents which a... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 2.2 Informative references | References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the reference document (including any amendments) applies. NOTE: While any hyperlinks in... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 3 Definitions and abbreviations | |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 3.1 Definitions | For the purposes of the present document, the following terms and definitions apply: acoustic echo: acoustic echoes consist of reflected signals caused by acoustic environments NOTE: In these acoustic environments, an echo path is introduced by the acoustic path from the loudspeaker or earpiece to the microphone, e.g. ... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 3.2 Abbreviations | For the purposes of the present document, the following abbreviations apply: ANM Answer Message ANS Answer Tone ATA Analog Terminal Adapter CED Called station identification tone CM Call Menu signal CM/JM Call Menu signal/Joint Menu signal CMD Circuit-Mode Data CNG Calling Tone CSS Composite Source Signal CT Calling To... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 4 Characteristics of de-jitter buffers | |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 4.1 De-Jitter buffers | The present document describes the activation procedures of a de-jitter buffer, including the requirement for in-band tone activating and other control mechanisms. The de-jitter buffers are assumed to be dynamic de-jitter buffers and fixed de-jitter buffers. Fixed de-jitter buffers shall be provided for fax and voiceba... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 4.2 Purpose, operation and environment | For proper operation for VBD-services, De-jitter buffers have the following fundamental requirements: 1) fast and correct switching between dynamic and fix de-jitter buffer mode; 2) proper operation during facsimile and data transmissions. For proper operation of speech services in good quality, false detection of tone... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 4.3 External enabling of fixed de-jitter buffers | The fixed de-jitter buffer for 64 kbit/s bit sequence (UDI) and V.152 VBD shall be activated directly by signalization. 5 Characteristics of VBD-mode switching of de-jitter buffers |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 5.1 General | The de-jitter buffer covered by the present document should be equipped with a tone detector that conforms to this clause. • The change of the de-jitter buffer to VBD-mode should be based on the following signals (mostly taken out of Recommendation ITU-T V.152 [9]) For Facsimile applications: - CED as per Recommendatio... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 5.2 Detector characteristics | |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 5.2.1 Detector characteristics for frequency range of 2 100 Hz ± 21 Hz | The tone detector shall detect a tone in the frequency range of 2 100 Hz ± 21 Hz (see Recommendation ITU-T V.21 [4]). The detection channel bandwidth should be chosen wide enough to encompass this tone (and possibly other tones used within national networks). At the same time, the detection channel bandwidth should be ... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 5.2.5 Detector characteristics for V.22 | To activate the De-jitter buffer at calling end respectively called end for procedures according to Recommendation ITU-T V.22 [5], the detector shall detect unscrambled binary 1 for 155 ± 50 ms from the calling terminal and Recommendation ITU-T V.25 [6] answer sequence from the called terminal. ETSI ETSI TS 102 929 V2.... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 5.2.6 Detector characteristics for 2 100 Hz with phase reversals (V.25) | Recommendation ITU-T V.25 [6] specifies the exchange of two tone signals: CT and ANS. To activate the De-jitter buffer at calling end respectively called end for procedures according to Recommendation ITU-T V.25 [6], the tone detector shall detect frequencies described in table 5. Table 5: Events for V.25 Signals Signa... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 5.2.7 Detector characteristics for Recommendation ITU-T V.32/V.32bis | Operating over the public telephone network, the start-up follows the V.25 answering procedure (see clause 5.2.4). Recommendation ITU-T V.32 [7] is a modem using phase-shift keying with quadrature amplitude modulation. It operates on a carrier at 1 800 Hz, modulated at 2 400 symbols/s. The basic data rates for Recommen... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 5.2.8 Detector characteristics for Recommendation ITU-T T.30 | To activate the De-jitter buffer at calling end respectively called end for procedures according to Recommendation ITU-T T.30 [i.10], the tone detector shall detect frequencies described in table 6. Table 6: Events for T.30 Signals Signal Frequency CED (Called tone which is physically identical to V.25 ANS) 2 100 Hz /C... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 5.2.9 Noise tolerance | The detector should operate correctly with white noise less than or equal to 11 dB below the level of the signal which should be detected. No definitive guidelines can be given for the range between 5 dB and 11 dB because of the variations in the test equipment used. In particular, performance may vary with the peak-to... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 5.2.10 Operate time | The operate time should be sufficiently long to provide immunity from false operation due to voice signals, but not so long as to needlessly extend the time to disable. The de-jitter buffer activator is required to operate within one second of the receipt of the activating signal. |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 5.2.11 False operation due to speech signals | It is desirable that the de-jitter buffer activator should rarely operate falsely on speech signals. To this end, a reasonable objective is that, for an de-jitter buffer installed on a working circuit, usual speech signals should not on the average cause more than 10 false operations during 100 hours of speech. In addi... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 5.2.12 Release time | For further study. |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 5.2.13 Other considerations | Both the echo of the activating tone and the echo of the calling tone may disturb the detection of the de-jitter buffer enabling tone. As such, it is not recommended to add the receive and transmit signal inputs together to form an input to a single detector. |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 6 Activation of de-jitter buffer for VBD | During telephony mode, the initiating station sends the calling tone (for fax called CNG, 1 100 Hz, a series of interrupted bursts of binary 1 signal or the 1 300 Hz signal (V.25) and while this takes place the user of the receiving station may be continuing to speak or send audio. The station on the left (figure 9) is... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 8 Requirements for values of de-jitter buffers | |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 8.1 Fixed de-jitter buffers | In case VBD it is the goal to keep the audio end-to-end delay constant during the entire call. The de-jitter buffer has to be implemented in such a way that any jitter occurring during the entire call will not change the end to end delay. The de-jitter buffer may adapt if there is an overflow or under run. |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 8.2 Adaptive de-jitter buffers | In case of voice the strategy of de-jitter buffer implementation is to keep the end to end audio delay as low as possible under all jitter conditions. Any de-jitter buffer implementation should mostly not impair the listening speech quality as perceived by the user. For voice calls between MSAN, IAD, MGW adaptive de-ji... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 8.3 Activation procedure into the fixed mode | The detection of the initiating calling tones should be maximal 200 ms, after that the De-jitter buffer shall adapt the de- jitter buffer state from the adaptive to the fixed de-jitter buffer state. "When the JB adapts to the fixed state, there will be some time (JB adaption time) without audio information due to the i... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 8.5 Handling of De-jitter buffer in case of lost or late packets | As the receiving decoder expects to be fed with voice packets at the same fixed rate, the de-jitter buffer shall insert dummy packets if the packets are lost, or they arrived too late. Depending of the De-jitter buffer algorithm, the lost packets will often be replaced with supposed audio information by a PLC-algorithm... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9 Echo canceller | |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9.1 Introduction | As a general rule, echo cancellers are required in VoIP systems due to the high transmission delay. In accordance with Recommendations ITU-T G.131 [i.5] and Q.115.1 [i.6] echo canceller (EC) according to Recommendation ITU-T G.168 [3] shall be used if the mean one way delay of the "talker echo transmission path" exceed... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9.2.1 General | The echo cancellers implemented according Recommendation ITU-T G.168 [3] should be equipped with a tone detector that conforms to this clause. This tone detector should disable the echo canceller only upon detection of a signal which consists of a 2 100 Hz tone with periodic phase reversals inserted in that tone, and n... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9.2.2 Detector characteristics | The tone detector shall detect a tone in the frequency range of 2 100 Hz ± 21 Hz (see Recommendation ITU-T V.21 [4]). The detection channel bandwidth should be chosen wide enough to encompass this tone (and possibly other disabling tones used within national networks). At the same time, the detection channel bandwidth ... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9.2.3 Phase reversal detection | The echo canceller tone disabler requires the detection of a 2 100 Hz tone with periodic phase reversals which occur every 450 ± 25 ms. The characteristics of the transmitted signal are defined in Recommendations ITU-T V.25 [6] and V.8 [1]. Phase variations in the range of 180° ± 25° should be detected while those in t... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9.2.4 Guard band characteristics | Energy in the voiceband, excluding the disable band, shall be used to oppose disabling so that speech will not falsely operate the tone disabler. The guard band should be wide enough and with a sensitivity such that the speech energy outside the disabling band is utilized. The sensitivity and shape of the guard band sh... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9.2.5 Noise tolerance | The detector should operate correctly with white noise less than or equal to 11 dB below the level of the 2 100 Hz signal. No definitive guidelines can be given for the range between 5 dB and 11 dB because of the variations in the test equipment used. In particular, performance may vary with the peak-to-average ratio o... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9.2.6 Holding-band characteristics | The tone detector, after disabling either the NLP or the echo canceller, should hold the NLP or echo canceller in the disabled state for tones in a range of frequencies specified below. The release sensitivity should be sufficient to maintain disabling for the lowest level data signals expected, but should be such that... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9.2.7 Operate time | The operate time should be sufficiently long to provide immunity from false operation due to voice signals, but not so long as to needlessly extend the time to disable. The tone disabler is required to operate within one second of the receipt of the disabling signal. The one second operate time permits the detection of... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9.2.8 False operation due to speech currents | It is desirable that the tone disabler should rarely operate falsely on speech. To this end, a reasonable objective is that, for an echo canceller installed on a working circuit, usual speech currents should not on the average cause more than 10 false operations during 100 hours of speech. In addition to the talk-off p... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9.2.9 False operation due to data signals | It is desirable that the tone disabler should rarely operate falsely on data signals from data sets that would be adversely affected by disabling the echo canceller. To this end, a reasonable objective is that, for an echo canceller installed on a working circuit, usual data signals from such data sets should not, on t... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9.2.10 Release time | The disabler should not release for signal drop-outs less than the ITU-T recommended value of 100 ms. To cause a minimum of impairment upon accidental speech disabling, it should release within 250 ms ± 150 ms after a signal in the holding band falls at least 3 dB below the maximum holding sensitivity in both direction... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 9.2.11 Other considerations | Both the echo of the disabling tone and the echo of the calling tone may disturb the detection of the echo canceller disabling tone. As such, it is not recommended to add the receive and transmit signal inputs together to form an input to a single detector. Careful attention should be given to the number of phase rever... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 10.2.0 Introduction | If voiceband data services should work on a similar level as they did on TDM, delay requirements as explained below are needed. Low delay requirements have the drawback, that only small amounts of IP delay variation and clock drift can be compensated. If the delay variation in a network is higher, this will give errors... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 10.2.1 Roundtrip delay | In the following clause the calculation of the requirements for send and receive delay are explained. For a telecommunication connection, only the roundtrip delay can be experienced. For this reason, also the requirement for MGWs is given also only for the roundtrip delay. Requirement Table 8 Codec T(ps) in ms T(rt) = ... |
60d313f651c6571cdda851ff4c0834a3 | 102 929 | 10.3.1 Roundtrip delay and IP packet loss ratio | The IP-based network should also be capable to carry the 64 kbit/s transparent data service described in Recommendation ITU-T I.231.1 [i.19], also known as "64 k clear-mode". The considerations of the IP packet loss ratio objective here are based on the Recommendation ITU-T G.826 [i.29]. The IP packet loss ratio object... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 1 Scope | The present document provides requirements on the quality parameters that need to be considered at the Segment-connection of Voice over IP (VoIP) services, voice band data (VBD) and conversational video service services in an IP Multimedia Core Network Subsystem. The present document provides requirements on objectives... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 2 References | References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the reference document (including any amendments) applies. Referenced documents which ar... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 2.1 Normative references | The following referenced documents are necessary for the application of the present document. Not applicable. |
22d75f47293672abaf64be8fbe527927 | 102 928 | 2.2 Informative references | The following referenced documents are not necessary for the application of the present document but they assist the user with regard to a particular subject area. [i.1] Recommendation ITU-T Y.1540 (2002): "Internet protocol data communication service - IP packet transfer and availability performance parameters". [i.2]... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 3 Definitions and abbreviations | |
22d75f47293672abaf64be8fbe527927 | 102 928 | 3.1 Definitions | For the purposes of the present document, the following terms and definitions apply: access segment: network segment from the customer interface (UNI) to the interface on the customer side of the first Gateway Router real time service: class of telecommunications service requiring information to be transmitted and deli... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 3.2 Abbreviations | For the purposes of the present document, the following abbreviations apply: AGW Access GateWay AS Application Server CPE Customer Premises Equipment DSL Digital Subscriber Line DSLAM Digital Subscriber Line Access Multiplexer ESR Errored Second Ratio ETH ETHernet GSM Global System for Mobile communications GSMA Global... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4 Reference Configuration | Compared to networks and systems that are circuit-based, those based on IP pose distinctly different challenges for planning and achieving the end-to-end performance levels necessary to adequately support the wide array of user applications (voice, data, fax, video, etc.). The fundamental quality objectives for these a... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.1 Generic Segment-connection Points | Due to real-world constraints the simplified static divisor approach according to Recommendation ITU-T Y.1542 [i.3] has been chosen for the impairment apportionment between access and transit networks. This approach "divides" the UNI-to-UNI path into three segments and budgets the impairments such that the total object... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.2 Transport Reference Parameters and Configurations | At the Segment-connection Points (figure 1) different access networks can be connected. The following access networks can be considered: • PSTN/ISDN classic access Configuration. • NGN PSTN/ISDN access Configuration. • Access DSL Configuration. • GSM. • UMTS. • LTE. In the following clauses are defined the end-to-end d... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.2.1 Reference Configurations | The following clauses describe the Backbone and access reference configuration. In the calculation is at the Segment-connection point taken into account only one SBC. |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.2.1.1 Backbone Configuration | Figure 3 shows the backbone configuration. ETSI ETSI TS 102 928 V1.1.3 (2014-09) 11 IP Transit SBC ADM DL CL SBC SBC SBC ADM DL CL Figure 3: Backbone |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.2.1.2 PSTN/ISDN classic access Configuration | Figure 4 shows the PSTN/ISDN classic access configuration. TE EC MGW SBC VoNGN PSTN Local exchange Transit exchange Figure 4: Reference configuration for PSTN/ISDN with classical access |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.2.1.3 NGN PSTN/ISDN access Configuration | Figure 5 shows the NGN PSTN/ISDN classic access configuration. TE SBC VoNGN PSTN EC Subscriber line digital junction MSAN (MGW) Figure 5: Reference configuration for NGN with PSTN/ISDN access |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.2.1.4 Access DSL/Ethernet Configuration | Figure 6 shows the xDSL access configuration. Figure 7 shows the Ethernet access configuration. Figure 6: Reference configuration for DSL access Figure 7: Reference configuration for Ethernet access |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.2.1.5 GSM Access configuration | Figure 8 shows the GSM access configuration. ETSI ETSI TS 102 928 V1.1.3 (2014-09) 12 Figure 8: Reference configuration for GSM Access |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.2.1.6 Access configuration from UMTS Release 4 | Figure 9 shows the UMTS Release 4 access configuration. Figure 9: Reference configuration from UMTS Release 4 |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.2.1.7 Access configuration from LTE | Figure 10 shows the LTE access configuration. Figure 11 shows the IMS signalling and media plane entities. Figure 10: Reference configuration from LTE Figure 11: IMS, VoLTE, GSM and UMTS signalling and media plane entities ETSI ETSI TS 102 928 V1.1.3 (2014-09) 13 |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.2.1.8 CPE reference configuration | The Jitter and Delay calculation is based on the fact that different terminals are connected at same time on the CPE. Figure 12: Terminal reference configuration for DSL access |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.3 Delay Values | The following clause 4.4 is based on the mathematical model described in TR 102 775 [i.20]. |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.3.1 Backbone Delay | Table 1 shows the long distance delay values for typical reference distances. Table 1: Long Distance Delay Distance Delay (propagation and equipment delay) 1 400 km 7 ms 5 000 km (Intra Regional) 25 ms 10 000 km (Inter Regional) 50 ms 20 000 km (Inter Regional) 100 ms 27 500 km (Inter Regional) 137 ms Table 2 shows del... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.4.1 Delay with regional propagation delay (1 400 km / 7 ms) | The regional reference configuration is based on a distance of 1 400 km which is the average value for intra - European regional calls. For the calculation of the Voice Quality parameters the used network parameters are contained in TR 102 775 [i.20], clause A.4. For the calculation were used the Packet sizes 10 ms and... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 4.4.2 Categories of User Satisfaction | The following information is an excerpt from Recommendation ITU-T G.109 [i.5]. While the single parameters describe the individual factors affecting speech transmission quality, it is the combined effect of all parameters together which leads to the overall level of speech transmission quality as perceived by the user.... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 5 Guidance on Segment-connection Objectives | QoS objectives in Y.1541 [i.2] are deemed to be applicable when access link speeds are at the T1 or E1 rate and higher. Today many network providers use technologies where they offer access link speeds much smaller then T1or E1. De-jitter buffers in international MGW are often limited to a size of 100 ms, and it is rec... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 5.1 Guidance on Access Segment Objectives | The following IPDV limits can be applied for access networks (between TE to included SBC). Table 5: Maximal IPDV values for xDSL and ETH Access Segment Nature of Network Application Jitter Value Access Network (sending side) Voice < 35 ms Conversational video < 5 ms Access Network (receiving side) Voice 10 ms (see note... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 5.2 Guidance on Total Transit Segment Objectives | The following objectives can be applied between: • Segment-connection point A Segment-connection point C. See figure 1 for details. The objectives are based on the application of Class 0 of Recommendation ITU-T Y.1541 [i.2]. The determination of cases where Class 1 of Recommendation ITU-T Y.1541 [i.2] should be appl... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 5.2.1 Availability | Values for availability are the following: • Availability of the IP Backbone Service Provider Core: 99,995 %. • Service Providers connection to IP Backbone Service Provider core with single connection: 99,7 %. • Service Providers connection to IP Backbone Service Provider core with dual connection: 99,9 %. |
22d75f47293672abaf64be8fbe527927 | 102 928 | 5.3 Voice Terminals | In order to be able to achieve the goal of users being satisfied or even very satisfied with the overall voice communication quality it is assumed that the VoIP terminals used in this context comply with one or more of the following ETSI standards: • ES 202 737 [i.6]. • ES 202 738 [i.7]. • ES 202 739 [i.8]. • ES 202 74... |
22d75f47293672abaf64be8fbe527927 | 102 928 | 6 End-to-End Aspects | Figure 14 presents the delay distribution between the calling and the called user. The delay of the calling user contains the packetization delay, the compression delay, the serialization time and the play out buffer size. The delay of the called user contains the decompression, the serialization time, the dejitterbuff... |
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