1、INTERNATIONAL TELECOMMUNICATION UNION CCITT THE INTERNATIONAL TELEGRAPH AND TELEPHONE CONSULTATIVE COMMITTEE TELEPHONE NETWORK AND ISDN QUALITY OF SERVICE, NETWORK MANAGEMENT AND TRAFFIC ENGINEERING E.701 (1 0/92) REFERENCE CONNECTIONS FOR TRAFFIC ENGINEERING Recommendation E.701 CCITT RECMN*E=70L 9
2、2 4862593 0576497 429 The CCITT (the Iiiteriiational Telegraph and Telephone Consultative Coininittee) is a perinaueut organ of the Iiiteriiatioual TelecoiriInuiiicatioti Union (ITU). CCITT is responsible for studying technical, operating aiid tariff questions and issuing Recotnrneudatioiis oti thei
3、n with a view to staudardizirig telecorninuuicatioris o11 a worldwide basis. The Plenary Assembly of CCITT which meets every four years, establishes the topics for study atid approves Recoinrneridatioris prepared by its Study Groups. The approval of Recommendations by the tnetnhers of CCITT betweeii
4、 Plenary Assemblies is covered by the procedure laid down in CCITT Resolutioii No. 2 (Melbouriie, 19x8). Recotntneudatioii E.701 was revised by Study Group II arid was approved under the Resolutioii No. 2 procedure oti the 30th October 1992. CCIT NOTES 1) telecoininuuicatiou admiiiistratiori aiid a
5、recognized private operating agency. Iii this Recotnineiidatioii, the expression “Admiiiistratioii” is used for conciseness to indicate both a 2) A list of abbreviations used iti this Recotnrnetidatiou cati be foutid iti Atitiex A. O IT 1993 All rights reserved. No part of this publication may be re
6、produced or utilized iii my fonn or by any inems, electronic or inech:uiic:il, iiicludiiig photocopying aid microfilm, without pennissioii in writing froin the ITU. Recommendation E.701 REFERENCE CONNECTIONS FOR TRAFFIC ENGINEERING (revised 1992) 1 General The goal of this Recommendation is to give
7、the E.700-Series Recommendations a hase to define ISDN Grade of Service GoS) and traffic parameters. In $2, two reference connections are defined. Definition of other reference connections is for further study. 2 Reference connections 2.1 Refirenre cnnnection for point-to-point circiiit switched ser
8、vices See Figure 1E.701. User B User A I TE Transit network S.S. No. 7 signalling network Rec. Q.931 User A Originating user User B Terminating user TE Terminal equipment LE Local exchange Note 1 - The transit network may contain zero, one, or more transit exchanges, which may or may not be dedicate
9、d ISDN exchanges. Nore 2 - The signalling network may contain zero, one, or more signalling transfer points. Nore 3 - The topology of the signalling network may differ significantly from that of the transit network. FIGURE 1/E.701 Reference connection for point-to-point circuit switched services Rec
10、ommendation E.701 (10/92) 1 CCITT RECMN*E.701 92 48b259L 057b499 2Tl 2.2 Reference connection for point-to-point packet switched services See Figure 2E.701. For more details, see Recommendation E.7 12. User A 07+ DTE - - User B Transit network Rec. X.75 - TA - TA - DTE - - User B T0203590-93 Rec. Q.
11、931 Ret. Q.931 User A Originating user User B Terminating user DTE Data terminal equipment TA Terminal adaptor LE Local exchange PH Packet handler Note 1 - The transit network may contain zero, one, or more transit exchanges. Nofe 2 - Current CCITT Recommendations support X.25 DTEs using X.31 TAS. N
12、ote 3 - The packet handler may be located outside the local exchange. FIGURE 2/E.701 Reference connection for point-to-point packet switched services ANNEX A (to Recommendation E.701) Alphabetical list of abbreviations used in this Recommendation DTE Data terminal equipment GOS Grade of service LE Local exchange PH Packet fiatidler TA Terminal adaptor TE Terminal equipment 2 Kecotninendation E.701 (10/92)
