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a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.1.1 SCN (Switched Communication Networks) | One of the main advantages of the world-wide telephony network is the existence of a universal numbering scheme for subscribers that is agreed upon internationally under the auspices of the ITU [27]. This universal numbering plan allows the provision of the universal communication service: any subscriber of a sub-netwo... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.1.2 IP-based networks | When IP was first standardized in September 1981, the specification required that each system attached to an IP-based Internet be assigned a unique, 32-bit Internet address value. Systems that have interfaces to more than one network require a unique IP address for each network interface. The first part of an Internet ... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.1.3 SCN-IP networks | One of the technical challenges raised by the integration between circuit-switched and IP networks is how to address calls that pass from one network service to another. Generally, it is assumed to be desirable to define an integrated global subscriber access plan. For example, the same ITU-T Recommendation E.164 [27] ... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.2 Media coding | This clause identifies the existing media coding technologies. |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.2.1 Voice coding | The purpose of voice coding is to transform a voice signal, generally analogue, into a digital signal of a given speed and quality. |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.2.1.1 Voice coding techniques in the context of the telephone network | Today's circuit switched telephone networks use, for the most part, coding systems based on the time technique, which is characterized by preservation of the waveform of the signal to be coded. According to the quantification method used, two types of coding can be identified: simple PCM (Pulse Coded Modulation) and di... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.2.1.2 Voice coding techniques in the context of an IP network | The speech encoders currently used for voice coding in IP networks may be grouped according to three major coding techniques: • Time techniques (bit rates between 16 and 64 kbit/s). • Parametric techniques (bit rates between 2,4 and 4,8 kbit/s). • Analysis-synthesis techniques (bit rates between 5 and 16 kbit/s). The f... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.2.1.3 Wideband speech coding techniques | Although most effort on speech coding focused on narrowband speech, the quality difference available by allowing the input speech to cover a larger bandwidth was recognized. The ITU-T established the first wideband speech coding standard, ITU-T Recommendation G.722, in 1998 [44]. ITU-T Recommendation G.722 [44] is simp... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.2.1.4 Still-image coding | Classic facsimile (G3, G4) - ITU-T Recommendations T.4 [48], T.6 [49] The ITU-T Recommendation T.4 [48] defines the characteristics of Group 3 facsimile terminals which enable black and white documents and also optionally colour documents to be transmitted on the general switched telephone network, international leased... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.2.1.5 Moving image coding | ITU-T Recommendation H.120 [60] ITU-T Recommendation H.120 [60] specifies codecs for videoconferencing using primary digital group transmission. It specifies how 625-line and 525-line television camera signals can be converted to a digital format suitable for transmission over broadband telephone services. ITU-T Recomm... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.2.1.6 ITU-R activities in broadcasting | ITU-R BS. 1115 (Low bit-rate audio coding) [67] ITU-R Recommendation BS. 1115 [67] addresses two-channel low bit-rate audio coding to be used for digital sound broadcasting applications. This recommendation specifies the audio coding systems and operational bit rate for four broadcasting applications: contribution, dis... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.3 QoS and performance | |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.3.1 Definitions and framework | There are several candidate definitions of quality and QoS (Quality of Service). While ISO 8402 [71] provides a general definition of quality itself, ITU-T Recommendation E.800 [72] provides a definition of QoS. A definition of general quality is provided in ISO 8402 [71] as "the totality of characteristics of an entit... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.3.2 End-to-end QoS for multimedia services and applications | It has to be taken into account that multimedia services and applications will have to support different kinds of audio, video and data (e.g. text, still images, graphics) combinations. However, each medium will have its own QoS requirements that are expressed to satisfy the needs of the user. These requirements are ex... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.3.3 End-user multimedia QoS categories | A typical user is not concerned with how a particular service is implemented. However, the user is interested in comparing the same service offered by different providers in terms of universal, user-oriented performance parameters. This implies that performance should be expressed by parameters that: • Take into accoun... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.3.4 QoS activities in standardization bodies | |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.3.4.1 ETSI EP TIPHON | ETSI EP TIPHON is working on end-to-end QoS issues (ETSI TR-STQ 037 - see bibliography) in a view of two aspects: • call quality (related to a quality of media transmission); • call set-up quality (characterized by the call-set up time as a principal parameter of signalling quality). As far as concerns the call quality... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.3.4.2 ITU-T | There are several Study Groups within ITU-T that are involved in QoS issues. ITU-T Recommendation SG 12 (End-to-end transmission performance of networks and terminals) ITU-T Recommendation SG 12 is responsible for guidance on the end-to-end transmission performance of networks, terminals and their interactions, in rela... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.3.4.3 3GPP IP Multimedia | The QoS issues are studied also in 3GPP. Work on the specifications for 3GPP is divided into Releases. The first release that addresses the use of a packet (IP) network infrastructure for voice and multi-media services is Release 5 which contains the IP Multimedia development, whose specifications are currently being c... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.3.4.4 ETSI IP Cablecom | ETSI's AT (Access and Terminals) Technical Committee is undertaking a programme of work adapting and developing further a set of specifications for IP-based cable networks. Initially the aim of IPCablecom is to support public telephony services with a quality that is at least as good as on the circuit switched networks... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.4 Security | |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.4.1 Security aspects | In the telecommunication sector, security has become an increasingly important requirement for the various players, i.e. users, who require that their communications be kept confidential; network operators and service providers, who need to protect their activities and financial interests; and finally, regulatory bodie... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.4.2 Security in PSTN/ISDN | One of the main differences between the PSTN/ISDN and IP networks lies in the concentration of intelligence and in processing within the network at the level of switching nodes. In the case of the PSTN/ISDN, protection is fully the responsibility of the network. The fact that the intelligence is located within the swit... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.4.3 Security in IP networks | In IP networks, most of the processing needed to establish calls is delegated to the user terminal equipment. The intelligence is hence deployed to the ends rather than to the nodes of the network, as in the case of traditional telecommunication networks. Thus, the security functions as well will to a large extent be e... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.4.4 Security for multimedia | In terms of multimedia services, security aspects become more complex, especially for two reasons: • specific nature of multimedia communication (diverse media, multiple streams within one communication); • the use of multimedia communications in the course of services and applications in new key areas such e-business,... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.4.5 Activities on security issues in standardization bodies | |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.4.5.1 ITU-T | ITU-T Recommendation SG 16 (Multimedia services, systems and terminals) ITU-T Recommendation SG 16 is aimed at security aspects and mechanisms for H.323-based multimedia systems. Recommendations relevant to security aspects include the following recommendations: • H.233 (Confidentiality system for audiovisual services)... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.4.5.2 ETSI | There is actually no TB (Technical Body) within ETSI directly related to security aspects of multimedia services. However, several TBs are working on security issues. ETSI SG SAGE (Special Committee Security Algorithms Group of Experts) The Security Experts Group is responsible for creating ETSI reports (containing con... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.4.5.3 IETF | There is the Security Area within the IETF that is responsible for development of security oriented protocols, security review of RFCs, development of candidate policies, and review of operational security on the Internet. Within the Security Area, several Working Groups have been active in defining security protocols ... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.4.5.4 ISO | There is the JTC1/SC27 "IT Security Techniques" Special Committee that is responsible for IT security aspects within ISO. Three Working Groups are currently active under the JTC1/SC27: • JTC1/SC27/WG1: "Requirements, security services and guidelines". • JTC1/SC27/WG2: "Security techniques and mechanisms". • JTC1/SC27/W... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.5 Network management | Network management can be presented as a set of tools, applications and devices to assist network managers in monitoring and maintaining networks. The main goals of the network management are to provide higher network availability, reducing network operational cost, reducing network bottlenecks, increase flexibility of... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.5.1 ISO network management model | The ISO network management model [140] is the primary means for understanding the major functions of network management systems. The model consists of five conceptual areas: • Fault management. • Configuration management. • Accounting management. • Performance management. ETSI ETSI TR 102 199 V1.1.1 (2003-10) 81 • Secu... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.5.2 Network Management protocols | SNMP (Simple Network Management Protocol) Network Management protocols started with SNMP in 1988. The protocol was meant to handle IP based networks. All versions (SNMPv1, SNMPv2, and SNMPv3) of the Internet-Standard Management Framework share the same basic structure and components. Furthermore, all versions of the sp... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.7 Multimedia mobility | |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.7.1 Nomadism, mobile communication and ad-hoc networking | Basically, there exist three scenarios for supporting mobility in the user's access to the communication service (Adam Wolisz: "Mobility in Multimedia Communication" - see bibliography). In the first one, frequently referred to as "nomadic", the travelling customer is interested in mobile access to communication servic... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.7.2 GMM (Global Multimedia Mobility) | The Global Multimedia Concept was defined was defined by ETSI in the Global Multimedia Report [146],[147]. It denotes the mobility aspects resulting from the convergence of telecommunications, information technology and entertainment services as envisaged by EII/GII. A basic assumption of the GMM concept is that, in th... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.7.3 ETSI EP TIPHON mobility service | Mobility in TIPHON compliant systems is based on the assumption that the five TIPHON scenarios [148] include end- to-end voice services when the user is mobile. Different aspects of mobility are distinguished as follows [149]: • User mobility - is the ability of a user to connect to, or use, different terminals or term... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.7.4 H.323 mobility | ITU-T Recommendation SG 16 is currently working on the Draft Recommendation H.510 - "Mobility for multimedia systems and services" (Draft Recommendation H.510 - Mobility for H.323 multimedia systems and terminals - see bibliography). The Draft Recommendation introduces new functionality to H.323 that enables mobility i... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.7.5 3GPP | 3GPP has specified mobility for UMTS OSA APIs [150]. The document specifies the Mobility SCF (Service Capability Feature) aspects of the interface. ETSI ETSI TR 102 199 V1.1.1 (2003-10) 87 |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 5.6.7.6 IETF | The Mobile IP Working Group has developed routing support to permit IP nodes (hosts and routers) using either IPv4 or IPv6 to seamlessly "roam" among IP subnetworks and media types. The Mobile IP method supports transparency above the IP layer, including the maintenance of active TCP connections and UDP port bindings. ... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6 Current situation in the standardization bodies | In this clause, an overview of the known key standardization bodies in the domain of technologies for broadband multimedia services and NGN is provided. The clause includes also related bodies, i.e. those that apply generic standards for technologies for broadband multimedia services and NGN to particular applications ... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.1 ETSI (European Telecommunications Standards Institute) | |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.1.1 Key ETSI TCs and Projects | ETSI TC SPAN (Services and Protocol for Advanced Networks) ETSI TC SPAN is ETSI's core competence centre for fixed networks standardization including IP based networks, especially for the development of signalling protocols. It is responsible for all aspects of standardization for present and future converged networks ... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.1.2 Related ETSI TCs and Projects | ETSI Project BRAN (Broadband Radio Access Networks) The project prepares standards for equipment providing broadband (25 Mbit/s or more) wireless access to wire-based networks in both private and public environments, operating in either licensed or license exempt spectrum. These systems address both business and reside... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.2 ITU-T | |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.2.1 Key ITU-T SGs and ITU-T Special Projects | ITU-T Recommendation SG 16 SG 16 is responsible for studies relating to multimedia service definition and multimedia systems, including the associated terminals, modems, protocols and signal processing. It is the lead Study Group on multimedia services, systems and terminals as well as the lead Study Group on e-busines... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.2.2 Related ITU-T SGs and ITU-T Special Projects | ITU-T Recommendation SG 9 SG 9 prepares and maintains Recommendations on the use of cable and hybrid networks, primarily designed for television and sound programme delivery to the home, as integrated broadband networks to also carry voice or other time critical services, video on demand, interactive services, etc., as... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.3 ISO (International Organization for Standardization) | Within the ISO, the JTC1 (Joint Technical Committee) is responsible for developing standards for information technology. The NGN-related issues are covering mainly by JTC/SC 6 (Telecommunications and information exchange between systems), JTC1/SC 27 (IT security techniques), and JTC1/29 (Coding of audio, picture, multi... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.4 ANSI (American National Standards Institute) | Within ANSI, it is Standards Committee T1 who develops American National Standards, technical reports and technical requirements for telecommunications services, network interconnection, interoperability, and performance. Committee T1 provides technical input to the United States Department of State supporting U.S. par... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.5 IETF | The actual technical work of the IETF is done in its working groups, which are organized by topic into several areas (e.g. routing, transport, security, etc.). Much of the work is handled via mailing lists. The IETF holds meetings three times per year. |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.5.1 Key IETF Technical Areas and Working Groups | Key technical areas and working groups involved in multimedia and NGN matters are: • Transport Area (e.g. avt - Audio/Video Transport, enum - Telephone Number Mapping, megaco - Media Gateway Control, midcom - Middlebox Communication, mmusic - Multiparty Multimedia Session Control, nsis - Next Steps in Signalling, sigtr... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.5.2 Related IETF Technical Areas and Working Groups | Related technical areas and working groups involved in multimedia NGN matters are: • Applications Area (calsch - Calendaring and Scheduling, cdi - Content Distribution Internetworking, ediint - Electronic Data Interchange-Internet Integration, geopriv - Geographic Location/Privacy, impp - Instant Messaging and Presence... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6 Other bodies | In this clause, some other bodies involved in the standardization process in the domain of technologies for broadband multimedia services and NGN will be overviewed. 6.6.1 ECMA (Europe-based Association for Standardizing Information and Communication Systems) TC32 is a Technical Committee of the Europe-based Associatio... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.2 DSL Forum | DSL Forum is a consortium of more than 400 leading industry players covering telecommunications, equipment, computing, networking and service provider companies. Established in 1994, the Forum continues its drive for a mass market for DSL, to deliver the benefits of this technology to end users around the world over ex... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.3 DVB (Digital Video Broadcasting) | The Digital Video Broadcasting Project is an industry-led consortium of over 300 broadcasters, manufacturers, network operators, software developers, regulatory bodies and others in over 35 countries committed to designing global standards for the global delivery of digital television and data services. The scope of th... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.4 IMTC (International Multimedia Telecommunications Consortium) | IMTC is an international community of companies working together to facilitate the availability of real-time, rich-media communications between people in multiple locations around the world. Rich Media refers to converged communications sessions that incorporate voice and one-way (or two-way) data and one-way (or two-w... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.5 IPCC (International Packet Communications Consortium) | The International Packet Communications Consortium evolved from the ISC (International Softswitch Consortium, the industry's most longstanding advocate advancing the maturation of packet-based network technologies and markets. The IPCC embodies the industry's primary mission: To develop the market for all products, ser... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.6 JAIN | The JAIN APIs are a set of Java technology based APIs which enable the rapid development of Next Generation telecom products and services on the Java platform. The JAIN APIs bring service portability, convergence, and secure network access to telephony and data networks. By providing a new level of abstraction and asso... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.7 MPLS and Frame Relay Alliance | Founded in March 2000, the MPLS and Frame Relay Alliance is an industry-wide organization of networking and telecommunication companies focused on driving the deployment of multi-vendor MPLS networks and associated applications. Through the efforts of our three working committees, the Forum encourages: (a) input to the... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.8 MSF (Multiservice Switching Forum) | The Multiservice Switching Forum is a global association of service providers and system suppliers committed to developing and promoting open-architecture, multiservice switching systems. The MSF's activities include developing implementation agreements, promoting worldwide compatibility and interoperability, and encou... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.9 PacketCable | PacketCable is a CableLabs-led initiative aimed at developing interoperable interface specifications for delivering advanced, real-time multimedia services over two-way cable plant. Built on top of the industry's highly successful cable modem infrastructure, PacketCable networks uses Internet protocol technology to ena... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.10 Parlay Group | The Parlay Group is a multi-vendor consortium formed to develop open, technology-independent APIs that enable the development of applications that operate across multiple, networking-platform environments. Parlay integrates IN services with IT applications via a secure, measured, and billable interface. By releasing de... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.11 TIA (Telecommunications Industry Association) | The Telecommunications Industry Association is the leading U.S. non-profit trade association serving the communications and information technology industry, with proven strengths in market development, trade shows, domestic and international advocacy, standards development and enabling e-business. Through its worldwide... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.12 W3C (World Wide Web Consortium) | The World Wide Web Consortium develops interoperable technologies (specifications, guidelines, software, and tools) to lead the Web to its full potential. W3C is a forum for information, commerce, communication, and collective understanding. W3C organizes the work necessary for the development or evolution of a Web tec... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.13 3GPP (3rd Generation Partnership Project) | The original scope of 3GPP was to produce globally applicable Technical Specifications and Technical Reports for a 3rd Generation Mobile System based on evolved GSM core networks and the radio access technologies that they support (i.e. UTRA (Universal Terrestrial Radio Access) both FDD (Frequency Division Duplex) and ... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 6.6.14 3GPP2 (Third Generation Partnership Project 2) | 3GPP2 is a collaborative third generation (3G) telecommunications specifications-setting project comprising North American and Asian interests developing global specifications for ANSI/TIA/EIA-41 Cellular radiotelecommunication Intersystem Operations network evolution to 3G and global specifications for the radio trans... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 7.1 Multimedia services | There is a need to standardize a minimum set of multimedia applications, services and interfaces which will fully meet evolving user needs. So far, there exists the ITU-T Recommendation F.700 [1] (applied to F.700-series of Recommendations) that provides a general methodology for description of services based on a modu... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 7.2 Accessibility | Possible areas of further investigation in the domain of xDSL technologies include the issues of interoperability among component manufactures and carriers, technical solutions for elimination of cross-talk interference from nearby wires and unification of power system requirements. However, there are especially human ... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 7.3 Control layer | The ETSI EP TIPHON is developing a generalized communications protocol to support voice services over IP with the emphasis initially on public telephony. This "meta-protocol" protocol is being mapped into actual protocols such as SIP and H.323 with the production of standards that are in effect a combination of profile... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 7.4 Service layer | Up to now, there is no criteria for selecting the most proper model, or technique for service development. ETSI should provide guidelines for selecting the most appropriate one based on several criteria: • Network characteristics, e.g. the abstraction of underlying network infrastructure that can be used by application... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 7.5 Issues affecting all layers | |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 7.5.1 Addressing, numbering and naming | Some of the issues which have been identified within the ITU IP Project (ITU-T IP Project Description - Version 7 - see bibliography) include: • accommodation of E.164 Number Portability; • allocation of E.164 resources to IP-based user; • E.164 - DNS interworking (definition of interworking concepts and principles, ad... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 7.5.2 Media coding | Based on the identification of emerging multimedia services and applications, the corresponding media that need to be encoded/decoded, or otherwise represented, should be identified. Other areas include security aspects (watermark, privacy) related to media coding, requirements on media coding to provide the same end-t... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 7.5.3 QoS | Since a multimedia service is a combination or set of combinations of two or more media components (e.g. audio, video, graphics, etc.), it is not appropriate to talk simply about "multimedia QoS". The approach needed is to define for each media component the appropriate QoS classes. Each media component and its QoS cla... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 7.5.4 Security | There are a lot of open issues in security for multimedia services. They can be grouped into several domains: • Security requirements and security services - Identification of multimedia applications and services that require security. - Identification of security services and mechanisms for the specified multimedia ap... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 7.5.5 Network management | The NGN is based on various forms of combined fixed, mobile, IP, etc. access networks. This fact creates increasing complexities and challenges related to the management of such networks. This also applies to the management of existing and new services, including multimedia ones across different network types. Integrat... |
a90e8f53dc74ce8384544d0f30284f3d | 102 199 | 7.5.7 Mobility | The principal objective should be to introduce mobility to a federation of converged networks, i.e. the possibility to offer roaming (user service delivery) and handover (maintaining a continuous service) via different access technologies and networks in such a way the AAA, security and QoS issues will be considered du... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 1 Scope | The present document provides background to the subject of measurement uncertainty and proposes extensions and improvements relevant to radiated measurements. It also details the methods of radiated measurements (test methods for mobile radio equipment parameters and verification procedures for test sites) and addition... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 2 References | For the purposes of this Technical Report (TR), the following references apply: [1] ITU-T Recommendation O.41: "Psophometer for use on telephone-type circuits". [2] ITU-T Recommendation O.153: "Basic parameters for the measurement of error performance at bit rates below the primary rate". [3] ETSI TR 100 027: "Electrom... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 3 Definitions, symbols and abbreviations | |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 3.1 Definitions | For the purposes of the present document, the following terms and definitions apply: accuracy: this term is defined, in relation to the measured value, in clause 4.1.1; it has also been used in the remainder of the document in relation to instruments Audio Frequency (AF) load: normally a resistor of sufficient power ra... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 3.2 Symbols | For the purposes of the present document, the following symbols apply: β 2π/λ (radians/m); γ incidence angle with ground plane (°) λ wavelength (m) φH phase angle of reflection coefficient (°) η 120π Ohms - the intrinsic impedance of free space (Ω) µ permeability (H/m) AFR Antenna Factor of the receive antenna (dB/m) A... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 3.3 Abbreviations | For the purposes of the present document, the following abbreviations apply: AF Audio Frequency A-M1 is a test modulation consisting of a 1 000 Hz tone at a level which produces a deviation of 12 % of the channel separation A-M2 is a test modulation consisting of a 1 250 Hz tone at a level which produces a deviation of... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 4 Introduction | A Test Fixture is usually constructed for testing a specific EUT. It consists of a 50 Ω RF connector and a device for electromagnetically coupling to the EUT. It should also incorporate a means for repeatable positioning of the EUT. Figure 1 illustrates a typical Test Fixture. ETSI ETSI TR 102 273-6 V1.2.1 (2001-12) 14... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 4.1 Performance limitations | The coupling mechanism between the EUT and the test fixture is extremely complex since the two are placed physically and electrically very close together. This complexity makes any attempt at theoretically modelling a test fixture's performance not only very difficult but also time consuming and costly. In practice, th... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 4.2 Summary | Test Fixtures are tools that allow the measurement of certain radio parameters of an EUT whilst it is subjected to extremes of either voltage or temperature or both. They only allow relative measurements to be carried out since its coupling mechanism to the EUT is extremely complex, making it virtually impossible to ca... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 5 Uncertainty contributions specific to test fixtures | There are essentially two main sources of error that contribute to tests involving a test fixture. Firstly, the effect that the close physical presence of the test fixture has on the EUT and secondly the overall effect produced by the climatic facility. Both these sources are quite complex and are discussed below. ETSI... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 5.1 Test Fixture effect | This effect is a result of the close proximity of the test fixture to the EUT. It is a combination of a detuning effect on the EUT produced by the dielectric constant of the materials from which the test fixture is constructed and various mutual coupling and reflection effects arising from the interaction between the E... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 5.2 Climatic facility effect | This effect can be broken down into several constituent parts. These parts include resonances due to the dimensions of the climatic facility itself, internal reflections from the metallic walls, mutual coupling effects and the possible propagation of waveguide type modes. All of these effects cause disruption to the fi... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 5.2.1 Resonances within a climatic facility | To fully contain and control the extreme conditions in which the EUT is tested, the test fixture is usually placed within a climatic test facility. For those cases in which the sides of the climatic facility are metal, the enclosed chamber will, by acting as a waveguide cavity, exhibit resonances. (Non metallic walls w... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 5.2.2 Internal reflections using a climatic facility | Multiple reflections, from the internal walls of a climatic facility, may seriously affect the uniformity of the field distribution. The magnitude of this effect becomes, in general, greater with increasing frequency. Where the wavelength of the test frequency is significantly shorter than the dimensions of the chamber... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 5.2.3 Mutual coupling effects using a climatic facility | Mutual coupling effects resulting from multiple imaging (again in the walls of the climatic facility) of the antenna/coupling device will change its input impedance, radiation pattern and gain. These effects tend to reduce with increasing frequency. In this case too, ferrite tiles (or grids) could reduce the uncertaint... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 5.2.4 Waveguide-type modes within a climatic facility | In addition to resonance effects, a further problem that results from using metallic climatic facilities, is the possible propagation of transverse electric and transverse magnetic (waveguide-type) modes. These can be generated by a number of mechanisms, amongst which are the size and shape of the EUT and the materials... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 5.2.5 Summary | To an extent, the overall effect on the performance of the EUT, produced by the climatic facility effect, is determined during the verification procedure. Its magnitude is used to determine whether the test fixture/climatic facility combination is acceptable. uj61 is used for the uncertainty contribution associated wit... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 6 Verification procedure for a test fixture | |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 6.1 Definition | Field normalization Field normalization is the process in which an EUTs performance on a free field test site is compared to its performance in a test fixture, both tests being carried out at the same verified free field test site under normal conditions of temperature and voltage. |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 6.2 Overview of the verification procedure | The verification procedure determines whether or not the test fixture has an unacceptably adverse effect on the EUT. An "adverse effect" could be the carrier frequency or receiver tuning being "pulled" to a higher or lower frequency, the output power level changing, etc. The end result of an adverse effect is a change ... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 6.2.1 Apparatus required | The verification of a test fixture is carried out at an accredited free field test site using the test equipment listed in the relevant test method described in TR 102 273-2 [5], TR 102 273-3 [6] or TR 102 273-4 [7]. Additional apparatus required: - 50 Ω load (type and sex of connector compatible with the test fixture ... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 6.2.2 Site preparation | The site preparation is the same as required in the relevant part of TR 102 273 for the free field test site. Additionally, for the test fixture, the cables supplying power to the EUT should be as short as possible, twisted together and loaded with ferrite beads spaced 0,15 m apart. The RF cables should be routed by th... |
389075c18860e0351ee27a1af78d6a3c | 102 273-6 | 6.2.3 Measurement configuration | Testing on the free field test site involves measuring the same EUT parameter both with and without the test fixture. To reduce unnecessary measurement uncertainties, it is important that the EUT should be positioned in precisely the same place for both of these tests. |
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