1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU v.110 SERIES V: DATA COMMUNICATION OVER THE TELEPHONE NETWORK Interworking with other networks (02/2000) Support by an ISDN of data terminal equipments with V-series type interfaces ITU-T Recommendation V. 1
2、1 O (Formerly CCITT Recommendation) ITU-T V-SERIES RECOMMENDATIONS DATA COMMUNICATION OVER THE TELEPHONE NETWORK General Interfaces and voiceband modems Wideband modems Error control Transmission quality and maintenance v.1-v.9 v. 104.34 v.35-v.39 v.40-v.49 v.50-v.59 Simultaneous transmission of dat
3、a and other sinnals V.60-V.99 - Interworking with other networks v.1oev.199 Interface layer specifications for data communication V. 2004.249 Control procedures Modems on digital circuits V. 2504.299 V.300-V.399 For further details, please rer to ITD-T List of Recommendations. ITU-T RECOMMENDATION V
4、.110 SUPPORT BY AN ISDN OF DATA TERMINAL EQUIPMENTS WITH V-SERIES TYPE INTERFACES Summary This Recommendation defines terminal adaptor (TA) functions for the connection of terminals having interfaces conforming to current V-series Recommendations to the ISDN for both circuit switched and leased circ
5、uit services. This includes the following functions: - - bit rate adaption; - - conversion of electrical and mechanical interface characteristics; end-to-end synchronization of entry to and exit fiom the data transfer phase; call establishment and disestablishment based on either manual or automatic
6、 calling andor automatic answering; local and end-to-end flow control to support DTEs of differing rates. - Source ITU-T Recommendation V. 1 10 was revised by ITU-T Study Group 16 (1997-2000) and was approved under the WTSC Resolution No. 1 procedure on 17 February 2000. Recommendation V.110 (02/200
7、0) 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 ITU-T is responsible for studying technical, operating and tariff quest
8、ions 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 for study by the ITU-T Study Groups which, in their turn, produce Recomme
9、ndations 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 necessary standards are prepared on a collaborative basis with IS0 and I
10、EC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS The ITU draws attention to the possibility that the practice or implementation of this Recommen
11、dation may involve the use of a claimed Intellectual Property Right. The ITU takes no position 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 ap
12、proval of this Recommendation, the ITU had not received notice of intellectual property, protected 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 th
13、e TSB patent database. o ITU 2000 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing fi-om the ITU. 11 Recommendation V.110 (02/2000) CONTENTS 1 2 3
14、4 4.1 4.2 5 5.1 5.2 5.3 5.4 6 6.1 6.2 6.3 6.4 6.5 6.6 Scope . References . Abbreviations Reference configurations Terminal adaptor reference model Connection types . Line signals at S and T reference points . Bit rate adaption of synchronous data signalling rates up to 38.4 kbitls . 5.1.1 General ap
15、proach . 5.1.2 Adaption of V-series data signalling rates to the intermediate rates . 5.1.3 5.1.4 Adaption of intermediate rates to 64 kbitls . Rate adaption of 48 and 56 kbitls synchronous user rates to 64 kbitls . Adaption for asynchronous rates of up to 38 400 bitls . 5.3.2 Frame synchronization
16、and additional signalling capacity 5.2.1 Frame synchronization . 5.3.1 General approach . Supported asynchronous user rates 5.3.3 Asynchronous-to-synchronous conversion (RAO) . 5.3.4 Overspeedhnderspeed . 5.3.5 Break signal . 5.3.6 Parity bits . Flow control for use with TAS supporting asynchronous
17、DTEs . Local flow control: between TA and DTE End-to-end (TA-to-TA) flow control . Use of channel capacity . Requirements of a TA supporting flow control . 5.4.1 5.4.2 5.4.3 5.4.4 Interchange circuits . Essential and optional interchange circuits . Timing arrangement Circuit 106 Circuit 1 O9 Electri
18、cal/mechanical characteristics of interchange circuits . Basic ISDN userhetwork interface . 6.5.2 TEYTA (DTE/DCE) interface Fault condition on interchange circuits . 6.5.1 Recommendation V.110 (02/2000) 1 2 3 4 4 4 4 4 4 5 11 13 13 14 15 15 15 16 16 16 17 17 17 18 18 19 19 19 20 20 20 20 20 21 21 .
19、111 Page 7 7.1 Operating sequence . TA duplex operation . 7.1.1 Idle (or ready) state 7.1.2 Connect TA to line state 7.1.3 Data transfer state 7.1.4 Disconnect mode . 7.1.5 Loss of fiame synchronization . 7.2 TA half-duplex operation 7.3 Automatic calling 8 Network-independent clocks 8.2 Positiveheg
20、ative compensation 8.1 Measurement of phase differences 8.3 Encoding . 9 In-band parameter exchange state . 1 O Testing facilities Annex A . Reference configurations . V . 1 1 O terminal adaptor reference model . A.3 Terminal adaption type . A . 1 Introduction . A.2 A.3.1 Terminal adaptor - Type A (
21、TA-A) A.3.2 Terminal adaptor - Type B (TA-B) . Types of end-to-end connection A.4 Appendix I . In-band parameter exchange Introduction . I . 1 1.2 Definitions 1.3 Overview . 1.4 Reference configuration 1.5 Procedwes . 1.5.1 General . 1.5.2 Initiating the exchange . Re-synchronization to a new interm
22、ediate rate Interworking with a TA not supporting IPE Re-entering IPE fiom the data transfer state 1.5.3 Parameter exchange . 1.5.4 1.5.5 Data transfer . 1.5.6 I . 5.7 Maintenance . 1.5.8 iv Recommendation V.110 (02/2000) 21 21 22 22 23 23 24 24 25 25 25 27 27 27 27 27 27 27 28 28 29 29 30 30 31 31
23、32 32 32 33 34 36 37 37 37 38 1.5.9 Error protection and handling 1.6 Coding . 1.6.1 General . 1.6.2 Rate adaption version identification 1.6.3 Control . 1.6.4 Parameters . 1.6.5 Status . 1.6.6 Maintenance . 1.7 Timer values . Timer values for parameter exchange Timer values for maintenance . 1.8 St
24、ate transition diagrams . 1.8.1 General . 1.7.1 1.7.2 Appendix II . V.25 bis to 4.93 1 protocol mapping . II . 1 General 11.2 Call origination . II.2.1 Call Set-up II.2.2 Call received rom remote DTE/TA Call clearing (Figues II.2 and 11.3). II.3.1 DISCONNECT (Irom TA) II.3.2 DISCONNECT (Irom exchang
25、e) . II.3.3 DISCONNECT (In-band between TAS) II.3.4 RELEASE COMPLETE II.3.5 Negative response to an incoming call 11.4 Direct call II.4.1 Direct call DTE call Set-up and clearing II.4.2 Direct call DCE call Set-up and clearing . Mapping of 4.93 1 causes to V.25 bis call failure indications and respo
26、nses . Additional information for handling of exception situations II.6.1 Call collision II.6.2 No channel available II.6.3 Premature call clearing 11.3 11.5 II . 6 Page 38 38 38 40 41 41 44 44 45 45 45 46 46 51 51 52 52 52 53 53 53 55 55 55 56 56 56 57 59 59 59 59 Recommendation V.110 (02/2000) V R
27、ecommendation V.110 SUPPORT BY AN ISDN OF DATA TERMINAL EQUIPMENTS (Malaga-Torremolinos, 1984; amended at Melbourne, 1988; revised at Geneva in 1992, 1996 and 2000) WITH V-SERIES TYPE INTERFACES 1 Scope The ITU-T, considering a) that the ISDN will offer the universal interfaces to connect subscriber
28、 terminals according to the reference configuration described in Recommendation 1.4 1 1 ; b) that during the evolution of ISDN, however, there will exist for a considerable period data terminal equipments (DTEs) with V-series type interfaces which have to be connected to the ISDN; c) that bearer ser
29、vices supported by an ISDN are described in Recommendation 1.2 1 1 ; d) that the D-channel signalling protocol is described in Recommendations 1.430, 4.921 and 4.93 1, unanimously declares the view 1 that the scope of this Recommendation shall cover the connection of terminals with interfaces for mo
30、dems conforming to current V-series Recommendations on the ISDN operating in accordance with circuit switched or leased circuit services; 2 that the following circuit switched service capabilities shall be supported: - data transmission; (and optionally) - automatic calling andor automatic answering
31、; 3 that the reference configurations of clause 4 shall apply; 4 that the support of intenvorking of terminal equipments (TES) on an ISDN with DTEs on other types of networks, e.g. public switched telephone network (PSTN), is described in the 1.500-series Recommendations; 5 that the terminal adaptor
32、 (TA) functions necessary to support the connection of DTEs with V-series type interfaces on an ISDN shall include the following: - conversion of electrical and mechanical interface characteristics; - bit rate adaption; - end-to-end synchronization of entry to and exit fiom the data transfer phase;
33、- call establishment and disestablishment based on either manual or automatic calling andor automatic answering; that optionally, the following may be included: local and end-to-end flow control to support DTEs of differing bit rates. 6 - Recommendation V.110 (02/2000) 1 2 References The following I
34、TU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; all users of this Recomme
35、ndation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. - - ITU-T Recommendation 1.4 1 1 (1 993), ISDN user-network intefl
36、aces - Reference ITU-T Recommendation 1.2 1 1 (1 993), B-ISDN service aspects. configurations. ITU-T Recommendation 1.430 (1995), Basic user-network interface - Layer 1 specijkation. ITU-T Recommendation 1.431 (1993), Primary rate user-network interface - Layer 1 specijkation. ITU-T Recommendation 1
37、.460 (1 999), Multiplexing, rate adaption and support of existing inteflaces. ITU-T Recommendation 1.463 (1996), Support by an ISDN of data terminal equipments with V-series type interfaces. ITU-T Recommendation 1.5 15 (1993), Parameter exchange for ISDN interworking. ITU-T Recommendation 1.530 (199
38、3), Network interworking between an ISDN and a public switched telephone network (PSnV). ITU-T Recommendation 4.921 (1.441) (1997), ISDN user-network inteflace - Data link layer specijkation. - - - - 2 ITU-T Recommendation 4.93 1 (1.45 1) (1998), ISDN user-network inteflace layer 3 specijkation for
39、basic call control. ITU-T Recommendation V. 1 O (X.26) (1 993), Electrical characteristics for unbalanced double-current interchange circuits operating at data signalling rates nominally up to 1 O0 kbith. ITU-T Recommendation V. 1 1 (X.27) (1996), Electrical characteristics for balanced double- curr
40、ent interchange circuits operating at data signalling rates up to 1 O Mbith. ITU-T Recommendation V. 14 (1993), Transmission of start-stop characters over synchronous bearer channels. ITU-T Recommendation V.24 (1996), List of definitions for interchange circuits between data terminal equipment TE) a
41、nd data circuit-terminating equipment CE). ITU-T Recommendation V.25 bis (1 996), Synchronous and asynchronous automatic dialling procedures on switched networks. ITU-T Recommendation V.28 (1 993), Electrical characteristics for unbalanced double- current interchange circuits. ITU-T Recommendation V
42、.43 (1998), Dataflow control. ITU-T Recommendation V.54 (1988), Loop test devices for modems. ITU-T Recommendation X. 1 (1996), International user classes of service in, and categories of access to, public data networks and Integrated Services Digital Networks (ISDNs). ITU-T Recommendation X.21 (199
43、2), Interface between Data Terminal Equipment and Data Circuit-terminating Equipment for synchronous operation on public data networks. Recommendation V.110 (02/2000) ITU-T Recommendation X.30 (1.461) (1993), Support ofX21, X21 bis andX20 bis based Data Terminal Equipments PTES) by an Integrated Ser
44、vices Digital Network (ISON). ITU-T Recommendation X. 150 (1988), Principles of maintenance testing for public data networks using Data Terminal Equipment PTE) and Data Circuit-Terminating Equipment CE) test loops. ISO/IEC 2 1 10: 1989, Data communication - 25-pole DTE/DCE interface connector and co
45、ntact number assignments. ISO/IEC 2593 : 1993, Information technology - Telecommunications and information exchange between systems - 34-pole DTE/DCE interface connector mateability dimensions and contact number assignments. IS0 4902: 1989, Information technology - Data communication - 37-pole DTE/D
46、CE inteflace connector and contact number assignments. ISO/IEC 1 1569: 1993, Information technology - Telecommunications and information exchange between systems - 26-pole inte flace connector mateability dimensions and contact num ber assignments. Abbreviations This Recommendation uses the followin
47、g abbreviations: CFI Call Failure Indication CRI Call Request with Identification CRN Call Request with Number DC Device Control DC 1 Device Control one DC3 Device Control three DCE Data Circuit-Terminating Equipment DTE Data Terminal Equipment DTR Data Terminal Ready IA5 International Alphabet No.
48、5 ISDN Integrated Services Digital Network IS0 International Organization for Standardization IWF Intenvorking Function NT Network Termination PARAM-X Parameter X (X = O, 1,2, 3,4) PPm parts per million PSTN Public Switched Telephone Network RA Rate Adaption RD Received Data TA Terminal Adaptor TA-A
49、 TA-B Terminal Adaptor - Type A Terminal Adaptor - Type B Recommendation V.110 (02/2000) 3 TD TE TE 1 TE2 TH Tn 4 4.1 Transmitted Data Terminal Equipment Terminal Equipment type 1 Terminal Equipment type 2 Threshold Timer n (n = 1,2, 3) Reference configurations Terminal adaptor reference model The terminal adaptor functions have been defined in the context of a simple reference model. Annex A describes the reference model in Mer detail, and defines a basic terminal adaptor TA-A, and an auto-calling/auto-answering terminal adaptor TA-B. 4.2 Connection types The terminal adaptor functio
