1、I l INTERNATIONAL TELECOMMUNICATION UNION lTU=T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU 1.741 (0699) SERIES I: INTEGRATED SERVICES DIGITAL NETWORK B-ISDN equipment aspects - Transport functions Interworking and interconnection between ATM and switched telephone networks for the transmission
2、of speech, voiceband data and audio signals ITU-T Recommendation I .741 (Previously CCITT Recommendation) STD*ITU-T RECMN 1-74L-ENGL L999 M 48b259L 0663776 726 ITU-T I -S ER I ES REC O M M EN DATIONS INTEGRATED SERVICES DIGITAL NETWORK IENERAL STRUCTURE Terminology Description of ISDNs General model
3、ling methods Telecommunication network and service attributes General description of asynchronous transfer mode Scope General aspects of services in ISDN Common aspects of services in the ISDN Bearer services supported by an ISDN Teleservices supported by an ISDN Supplementary services in ISDN Netwo
4、rk functional principles Reference models Numbering, addressing and routing Connection types Performance objectives Protocol layer requirements General network requirements and functions Application of I-series Recommendations to ISDN user-network interfaces Layer 1 Recommendations Layer 2 Recommend
5、ations Layer 3 Recommendations Multiplexing, rate adaption and support of existing interfaces Aspects of ISDN affecting terminal requirements ;ERVICE CAPABILITIES 3VERALL NETWORK ASPECTS AND FUNCTIONS ISDN USER-NETWORK INTERFACES INTERNETWORK INTERFACES MAINTENANCE PRINCIPLES B-ISDN EQUIPMENT ASPECT
6、S ATM equipment 1.110-1.119 I. 120-1.129 I. 130-1.1 39 1.1 40-1.1 49 I. 1 50-1.1 99 1.200-1.209 I .2 1 0-1.2 1 9 1.220-1.229 1.230-1.239 1.240-1.249 1.250-1.299 1.310-1.319 1.320-1.329 1.330-1.339 I. 3404.349 1.350-1.359 I .360-1.369 I .370-1.399 1.420-1.429 I .430-1.439 I .440-1.449 1.450-1.459 1.4
7、60-1.469 i .470-1.499 1.500-1.599 1.600-1.699 1.730-1.739 Transport functions I. 740-1.749 Management of ATM equipment I .750-1.799 For further details, please refer to ITU-T List of Recommendations ITU-T RECOMMENDATION 1.741 INTERWORKING AND INTERCONNECTION BETWEEN ATM AND SWITCHED TELEPHONE NETWOR
8、KS FOR THE TRANSMISSION OF SPEECH, VOICEBAND DATA AND AUDIO SIGNALS Summary This Recommendation provides requirements for the intenvorking and interconnection functions between public ATM and other types of public switched telephone networks (including wireless networks) for the transmission of spee
9、ch, voiceband data and audio signals. The functions include: interfaces of TDM to ATM networks, TDM to ATM conversion, transport, multiplexing, switching and echo cancellation. Source ITU-T Recommendation 1.741 was prepared by ITU-T Study Group 15 (1997-2000) and was approved under the WTSC Resoluti
10、on No. 1 procedure on the 22nd of June 1999. Recommendation 1.741 (06/99) 1 FOREWORD ITU (International Telecommunication Union) is the United Nations Specialized Agency in the field of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of the ITU. The
11、ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication standardization Conference (WTSC), which meets every four years, establishes the topics fo
12、r study by the ITU-T Study Groups which, in their turn, produce Recommendations on these topics. The approval of Recommendations by the Members of the ITU-T is covered by the procedure laid down in WTSC Resolution No. 1. In some areas of information technology which fall within ITU-Ts purview, the n
13、ecessary standards are prepared on a collaborative basis with IS0 and IEC. NOTE In this Recommendation the term recognized operating agency (ROA) includes any individual, company, corporation or governmental organization that operates a public correspondence service. The terms Administration, ROA an
14、d public correspondence are defined in the Constitution of the ITU (Geneva, 1992). INTELLECTUAL PROPERTY RIGHTS The ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. The ITU takes no positio
15、n concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, the ITU had not received notice of intellectual property, prot
16、ected by patents, which may be required to implement this Recommendation. However, implementors are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database. O ITU 1999 All rights reserved. No part of this publication may be rep
17、roduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the ITU. 11 Recommendation 1.741 (0699) - STD-ITU-T RECMN 1.741-ENGL 3777 N 4862591 0563779 435 2 3 4 5 6 6.1 6.2 6.3 6.4 6.5 6.6 7 7.1 CONTENTS Scope R
18、eferences Abbreviations . Terms and definitions . Generic configuration of PSTN/N-ISDN/ATM intenvorkinglinterconnection Examples of networking scenarios . Interworking and interconnection . Scenario 1 : Reference PSTN/N-ISDN . Scenario 2: Reference ATM . Scenario 3 : ATM-PSTN interconnection and int
19、erworking . 6.4.1 Physical interfaces . 6.4.2 Service-related criterias . 6.4.3 AAL requirements . 6.4.4 Lost and misinserted cells . 6.4.5 Echo control 6.4.6 6.4.7 Scenario 4: PSTNN-ISDN-ATM-PSTN/N-ISDN interconnection and Traffic parameters and tolerances . Management and fault control interworkin
20、g . 6.5.1 Physical interfaces . 6.5.2 Service-related criterias . 6.5.3 AAL requirements . 6.5.4 Lost and misinserted cells . 6.5.5 Echo control 6.5.6 Traffic parameters and tolerances . 6.5.7 Scenario 5: Mobile-ATM-Mobile interconnection and interworking 6.6.1 Physical interfaces . 6.6.2 Service-re
21、lated criterias . 6.6.3 AAL requirements . 6.6.4 Lost and misinserted cells . 6.6.5 Echo control 6.6.6 6.6.7 Voiceband signals within the ATM networks Management and fault control Traffic parameters and tolerances . Management and fault control Cell fill Recommendation 1.741 (06/99) Page 1 1 3 4 4 5
22、 5 6 6. 6 7 7 10 10 11 11 11 12 12 12 13 13 13 13 13 13 14 14 14 14 14 15 15 15 15 . 111 7.2 Cell loss and recovery mechanism . 7.3 Jitter 7.4 Transcoding and gateway functions . 8 Additional details of PSTN/ATM intenvorking . 8.1 Echo cancellation . 8.2 Congestion control and flow control 8.3 DCME/
23、ATM interface consideration . 8.4 Interface to cellular networks . 8.5 TDM/ATM compression interface . Annex A - PSTN/N-ISDN-ATM interconnection using DCME A.l Background A.2 A.3 ATM-to-DCME interface . Routing and tandeming issues Appendix I . Timing issues related to echo cancellation in ATM netwo
24、rks I . 1 Introduction 1.2 Cell delay variation . 1.3 Eliminating or reducing the effects of CDV on timing 1.3.1 Network synchronous operation 1.3.2 1.3.3 Adaptive clock recovery Synchronous residual time stamp Echo canceller phase noise requirements . 1.4 1.5 Conclusions Page 15 15 16 16 16 16 17 1
25、7 17 18 18 19 20 20 20 21 24 24 25 28 40 40 iv Recommendation 1.741 (06/99) STD-ITU-T RECMN 1-741-ENGL 1999 48b2591 Ob63781 093 Recommendation 1.741 INTERWORKING AND INTERCONNECTION BETWEEN ATM AND SWITCHED TELEPHONE NETWORKS FOR THE TRANSMISSION OF SPEECH, VOICEBAND DATA AND AUDIO SIGNALS (Geneva,
26、1999) 1 Scope The scope of this Recommendation is to provide requirements for the interworking and interconnection functions between public ATM and other types of public switched telephone networks (including wireless networks) for the transmission of speech, voice band data and audio signals. The f
27、unctions include: interfaces of TDM to ATM networks, TDM to ATM conversion, transport, multiplexing, switching and echo cancellation. 2 References The following Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation
28、. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision: all users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references
29、listed below. A list of the currently valid ITU-T Recommendations is regularly published. - - - - - ITU-T Recommendation G.114 (1996), One-way transmission time. ITU-T Recommendation G. 13 1 (1 996), Control of talker echo. ITU-T Recommendation G. 165 (1 993), Echo cancellers. ITU-T Recommendation G
30、. 168 (1997), Digital network echo cancellers. ITU-T Recommendation G. 176 (1 997), Planning guidelines for the integration of A TA4 technology into networks supporting voiceband services. ITU-T Recommendation G.703 (1 998), Physicalelectrical characteristics of hierarchical digital interfaces. ITU-
31、T Recommendation G.704 (1998), Synchronous fame structures used at 1544, 6312, 2048, 8448 and 44 736 kbit/s hierarchical levels. CCITT Recommendation G.706 (i 991), Frame alignment and cyclic redundancy check (CRC) procedures relating to basic frame structures defined in Recommendation G. 704. ITU-T
32、 Recommendation G.707 (1996), Network node interface for the synchronous digital hierarchy (SOH). CCITT Recommendation G.7 1 1 (1 988), Pulse code modulation (PCM) of voice frequencies. CCITT Recommendation G.726 (1990), 40, 32, 24, l kbit/s adaptive differential pulse code modulation (ADPCM). CCITT
33、 Recommendation G.727 (1 990), 5-, 4-, 3-, and 2-bitdsample embedded adaptive differential pulse code modulation (ADPCM). CCITT Recommendation G.728 (1992), Coding of speech at 16 kbit/s using lowdelay code excited linear prediction. - - - - - - - - Recommendation 1.741 (06/99) 1 - ITU-T Recommendat
34、ion G.729 (1996), Coding of speech at 8 kbit/s using Conjugate- Structure Algebraic-Code-Excited Linear-Prediction (CS-ACELP). - CCITT Recommendation G.732 (1 988), Characteristics of primary PCM multiplex equipment operating at 2048 kbit/s. CCITT Recommendation G.75 1 (1 988), Digital multiplex equ
35、ipments operating at the third order bit rate of 34368 kbit/s and the fourth order bit rate of 139 264 kbit/s and using - positive justification. - ITU-T Recommendation G.763 (1 998) Digital circuit multiplication equipmeni ADPCM (Recornmendation G. 726) and digital speech interpolation. ITU-T Recom
36、mendation G.766 (1 996) Facsimile demodulatiodremodulation for circuit multiplication equipment. ITU-T Recommendation G.804 (1 998), ATM cell mapping into plesiochronous hierarchy (PDH). ITU-T Recommendation G.823 (1993), The control of jitter and wander within networks which are based on the 2048 k
37、bit/s hierarchy. ITU-T Recommendation G.824 (1993), The control of jitter and wander within networks which are based on the 1544 kbit/s hierarchy. - - - - using digital digital digital digital - ITU-T Recommendation G.832 (1998), Transport of SDH elements on PDH networks: Frame and multiplexing stru
38、ctures. ITU-T Recommendation G.957 (1 999, Optical interfaces for equipments and systems relating to the synchronous digital hierarchy. ITU-T Recommendation 1.356 (1 996), B-ISDN ATM layer cell transfer performance. ITU-T Recommendation 1.361 (1 999), B-ISDN ATM layer speciJication. ITU-T Recommenda
39、tion 1.363.1 (1 996), B-ISDN ATM Adaptation Layer specification: Type 1 AAL. ITU-T Recommendation 1.363.2 (1 997), B-ISDN ATM Adaptation layer specification: Type 2 AAL. ITU-T Recommendation 1.363.3 (i 996), B-ISDN ATM Adaptation Layer specification: Type 3/4 AA L. ITU-T Recommendation 1.363.5 (1 99
40、6), B-ISDN ATM Adaptation Layer specification: Type 5 AAL. ITU-T Recommendation 1.371 (1996), Traffic control and congestion control in B-ISDN. ITU-T Recommendation 1.580 (1 999, General arrangements for intenuorking between B-ISDN and 64 kbit/s based ISDN. ITU-T Recommendation 1.6 1 O (1 999), B-IS
41、DN operation and maintenance principles and functions. ITU-T Recommendation 1.75 1 (1 996), Asynchronous transfer mode management of the network element view. ITU-T Recommendation Q.50 (1997), Signalling between circuit multiplication equipments (CME) and international switching centres (ISC). ITU-T
42、 Recommendation Q. 1 15 (1 997), Logic for the control of echo control devices. ITU-T Recommendation 4.2660 (1 99.9, Intenuorking between Signalling System No. 7 - Broadband ISDN User Part (B-ISUP) and Narrow-band ISDN User Part (SJ-ISUP). - - - - - - - - - - - - - - 2 Recommendation 1.741 (0699) 3
43、Abbreviations This Recommendation uses the following abbreviations: AAL AAL cs ACR ADPCM ATM B-ISDN B-ISUP CDV CLP CLR CRC CS-ACELP DBR DCME I FDM I GFC HEC ISDN ISUP IWF LD-CELP MTE N-ISDN N-ISUP OAM PCM PRC PSTN PTI QOS SN SRTS TDM TE VCI ATM Adaptation Layer . AAL Convergence Sublayer Adaptive Cl
44、ock Recovery Adaptive Differential Pulse Code Modulation Asynchronous Transfer Mode Broadband-ISDN Broadband-ISUP Cell Delay Variation Cell Loss Priority Cell Loss Rate Cyclic Redundancy Check Conjugate-Structure Algebraic-Code Excited Linear Prediction Deterministic Bit Rate Digital Circuit Multipl
45、ication Equipment Frequency Division Multiplex Generic Flow Control Header Error Control Integrated Services Digital Network ISDN User Part Interworking Function Low-Delay Code Excited Linear Prediction Mobile Terminal Equipment Nmowband-ISDN Narrowband-ISUP Operation and Maintenance Pulse Code Modu
46、lation Primary Reference Clock Public Switched Telecommunication Network Payload Type Information Quality of Service Sequence Number Synchronous Residual Time Stamp Time Division Multiplex Teminal Equipment Virtual Channel Identifier Recommendation 1.741 (06/99) 3 I- STD.ITU-T RECMN 1.74L-ENGL 1999
47、E 4862593 Obb3784 8T2 m VCLAD VPI Virtual Path Identifier Voice Cell Assembly and Disassembly 4 Terms and definitions This Recommendation defines the following terms: 4.1 ATM island: An ATM island is a self-contained telecommunication infrastructure segment where access is provided exclusively by AT
48、M interfaces. Traffic outside an ATM island is typically transported by the PSTN. 4.2 Interconnection: This is the configuration when two like-network (e.g. ATM) islands are linked through a different network (e.g. PSTN) using a permanent circuit between them. Interconnection also covers the connect
49、ion of two non-ATM networks (e.g. PSTN/N-ISDN or mobile) through an ATM backbone. Examples of various ATM-PSTN/N-ISDN and ATMMobile Network scenarios are shown in clause 6. 4.3 Interworking: This is the configuration when an ATM network and another type of network (e.g. PSTN or mobile) are linked through the necessary functions to convert from one network format to the other and vice versa. These functions may include the mapping and demapping of voiceband signals and signalling conversion. 5 Figure 5-1 shows the generic interworking and interconnection of the cir
