1、INTERNATIONAL TELECOMMUNICATION UNION CCITT THE INTERNATIONAL TELEGRAPH AND TELEPHONE CONSULTATIVE COMMITTEE TELEPHONE NETWORK AND ISDN OPERATION, NUMBERING, ROUTING AND MOBILE SERVICE E.202 (1 0/92) NETWORK OPERATIONAL PRINCIPLES FOR FUTURE PUBLIC MOBILE SYSTEMS AND SERVICES Recommendation E.202 CC
2、ITT RECMN*E-202 92 = 4862591 0576446 Tb7 = FOREWORD The CCITT (the International Telegraph and Telephone Consultative Committee) is a permanent organ of the International Telecommunication Union (ITU). CCITT is responsible for studying technical, operating and tariff questions and issuing Recommenda
3、tions on them with a view to standardizing telecommunications on a worldwide basis. The Plenary Assembly of CCITT which meets every four years, establishes the topics for study and approves Recomrnendatious prepared by its Study Groups. The approval of Recommendations by the members of CCITT between
4、 Plencary Assemblies is covered by the procedure laid down in CCITT Resolution No. 2 (Melbourne, 1988). Recoininendation E.202 was prepared by Study Group II and was approved under the Resolution No. 2 procedure on the 30th of October 1992. CCIT NOTES 1) telecomunication administration (and a recogn
5、ized private operating agency. 2) In this Recommendation, the expression ?Administration? is used for conciseness to indicate both a A list of abbreviations used in this Recomeneneral principles 4.1 Iii general, the interconnection of future public mobile systems to the PSTNASDN, should not impose a
6、ny requirement for additional functionality in the current fixed network, nor any restriction in the iionnal operation of the fixed network (Recoinmendation E.220). Operational principles for grade of service should conform to the E.750- Series Recotnmeiirlatioris. In general, Quality of Service ati
7、d end-to-end iietwvork performance should conform to appropriate CCITT Recoinrnendatioiis. 3.2 the Quolity of Service provided on calls routed across the interconnection or within the integrated network. The iiitercoiiiiectioti and integration of future public mobile systems should not result in any
8、 impainnent to Recommendation E.202 (10/92) 1 - _. CCITT RECHN*E=202 92 m 4862593 O576448 83T m 5 Network operation 5.1 Generd 5.1.1 In principle networks used to support future mobile systems should be digital aid compatible with the ISDN. 5.1.2 with the IN principles and struidards produced by CCI
9、TT Where appropriate, Intelligent Network (IN) technology should be employed, and this should be compatible 5.2 Koumiiig 5.2.1 Mobile units in a future public mobile system may either travel within the home public network, across or within other public networks, or private customer premises networks
10、. Roaming requires the updating of a location data base for a inobile unit to provide service to the mobile unit when it is in the coverage area of a location data bise beyond its home network. This location inxiagemerit inay be handled by a distributed data base function. 5.2.2 mobile systems: Froi
11、n the location data base point of view, at least three roaming scenarios are possible for future public - inter-operator roaming (roaming between public networks); - intra-environment roaming (roaming within one public network); - inter-environment roauiiiig (ro,uning from a public network to a priv
12、ate customer premises network). 5.2.3 In principle, all inobile units should be able to initiate access to public networks operated by different operators as well as private customer premises networks. However, users should be able to m,i call hecause of inter-environment handover. Echo control devi
13、ces should be able to converge on new echo paths without injecting subjective impairments on calls. 5.3.7 In principle, priority should be given to the haidover of calls-in-progress over new cdl attempts. S.4 Grtide of serrice Grade of service should conform to the appropriate E.750-Series Recommend
14、ations. 5.5.1 conform to CCITT Recomineiiditions. In principle, data security mid voice privacy should be maintained in roaming and huidover and should 6 Signalling h. 1 Iii principle, the signalling systems used or deveqed for future mobile systems should be compatible with those utilized in the fi
15、xed network. The objective should be to in,wimize service ,and feature transparency, therehy reducing the need for complex interworking relationships between, and easing the integration of, fixed ,and inchile networks. 7. Transmission 7.1 General 7.1.1 In principle, the design of future mobile syste
16、ms should Le into account, the overall end-to-end traiismissicin perfonnaiice on all realistic connections. In particular, the cumulative effects of speech processing devices, hoth in the mobile network atid the fixed network should be considered. Recommendations G. 173, G.721, G.763 aiid P.94 refer
17、. 7.2 Triinsrnission delq 7.3.1 approximately 3.5 qdu between analogue interfaces. Speech quality should be as good as or better than Recornmeiidation G.721 (32 kbit/s ADPCM staridxd) with 7.3.2 Due consideration should be given to acoustic echoes in hands-free operating environment. Echo protection
18、 should conform with CCITT Recommendations in particular with Recoininendation E.220. 8 Reference configuratins 8.1 the fixed network. In the figure, the following network elements are defined: Figure la)/E.202 shows the case of a future mobile system operating as a stand-alone network connected to
19、Mobile unit, i.e. the user terminal. This is connected to the public network or a customer premises network through a radio path. The base station sub-system is composed of more than one physical network element. It may contain a base sttion controller and a number of base transceiver stations. The
20、inobile control node is responsible for all mobile specific control functions such as mobile call establishment, handover, and security. The local exchange has the capability associated with a mobile switching centre. The information storage node stores the information on location, terminal, subscri
21、ber, and services. MS: BSS: MCN: LE ISN: 8.2 this case, the local exchange has the capability of connecting base station sub-systems with MCNs. Figure lb)/E.202 shows the case of future mobile systems operating as sub-networks of the fixed network. In 9 History 4 Recommendation E.202 (10/92) First p
22、ublished in 1993. - CCITT RECMN*E-202 92 = 4862573 057b453 324 = MS & o BSS LE Uational fixed network MS fi u T BSS LE LE I ISC .c Other LES, TES MCN International fixed network 1 International network T0202960-92 ! a) A stand-alone mobile network T0202970-92 b) An htegrated mobile network FIGURE 1/
23、E.202 Recommendation E.202 (10/92) 5 ADPCM B-ISDN BSS IN ISC ISDN ISN LE MCN MS PSTN TE 6 ANNEX A (to Recoinineidatioii E.202) Alphabetical list of ablireviations used in this Kecommendation Adaptive differential pulse code inodulatioti Broadband integrated services digital network Base statiou sub-systein Iiitelligeti t network Iiiteriiatiotial switching centre Integrated services digital network Information storage node Local exchange Mobile control node Mobile unit Public switched telephone network Transit exchange Kecommendation E.202 (10192)
