1、STD-ITU-T RECMN SERIES SUPP 11-ENGL 1999 = 48b2591 Ob83891 7JT O INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Series Q Supplement I1 (1 2/1999) SERIES Q: SWITCHING AND SIGNALLING Technical Report TRQ.201 O: B4SDN signalling interworking requirements ITU
2、-T Q-series Recommendations - Supplement 1 I (Formerly CCIlT Recommendations) _ . STDmITU-T RECMN SERIES Q SUPP Irli-ENGL 3999 48b2593 Ob83892 b5b = ITU-T Q-SERIES RECOMMENDATIONS SWITCHING AND SIGNALLING SIGNALLING IN THE INTERNATIONAL MANUAL SERVICE INTERNATIONAL AUTOMATIC AND SEMt-AUTOMATIC WORKI
3、NG FUNCTIONS AND INFORMATION FLOWS FOR SERVICES IN THE ISDN CLAUSES APPLtCABLE TO ITU-T STANDARD SYSTEMS I SPECIFICATIONS OF SIGNALLING SYSTEMS NO. 4 AND NO. 5 SPECIFICATIONS OF SIGNALLING SYSTEM No. 6 SPECIFICATIONS OF SIGNALLING SYSTEM R1 SPECIFICATIONS OF SIGNALLING SYSTEM R2 DIGITAL EXCHANGES IN
4、TERWORKING OF SIGNALLING SYSTEMS SPECIFICATIONS OF SIGNALLING SYSTEM No. 7 DIGITAL SUBSCRIBER SIGNALLING SYSTEM No. 1 PUBLIC LAND MOBILE NETWORK INTERWORKING WITH SATELLITE MOBILE SYSTEMS INTELLIGENT NETWORK SIGNALLING REQUIREMENTS AND PROTOCOLS FOR IMT-2000 BROADBAND ISDN Q.1-Q.3 Q.4-Q.59 Q.60-Q.99
5、 Q.100-Q.119 Q.120-Q.249 Q.250-Q.309 Q.31O-Q.399 Q .40O-Q .499 Q. 500-Q.599 Q.600-Q.699 Q.700-Q.849 Q.850-Q.999 Q.1 O0 0-Q. 1 O99 Q.1100-Q.1199 Q.1200-Q.1699 Q.17004.1799 Q.20004.2999 For further details, please refer to ITU-T List of Recommendations. - STD-ITU-T RECMN SERIES Q SUPP IL-ENGL 1999 486
6、259L Ob83893 592 SUPPLEMENT 11 TO ITU-T Q-SERIES RECOMMENDATIONS TECHNICAL REPORT TRQ.2010: B-ISDN SIGNALLING INTERWORKING REQUIREMENTS Summary This Supplement specifies the B-ISDN signalling interworking requirements. Source Supplement 11 to ITU-T Q-Series Recommendations, was prepared by ITU-T Stu
7、dy Group 11 (1997-2000) and was approved under the WTSC Resolution No. 5 procedure on 3 December 1999. 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 perma
8、nent organ of the . The 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, e
9、stablishes the topics for 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 with
10、in ITU-Ts purview, the necessary standards are prepared on a collaborative basis with IS0 and IEC. NOTE In this publication, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS The
11、 ITU draws attention to the possibility that the practice or implementation of this publication 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
12、members or others outside of the publication development process. As of the date of approval of this publication, the ITU had not received notice of intellectual property, protected by patents, which may be required to implement this publication. However, impiementors are cautioned that this may not
13、 represent the latest information and are therefore strongly urged to consult the TSB patent database. o ITU 2001 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 permis
14、SIon in writing from the lTU- STD-ITU-T RECMN SERIES Q SUPP LI-ENGL 1999 4862571 Ob83895 365 m CONTENTS Page 1 Scope 1 2 References 1 3 Definitions 1 4 Abbreviations . 1 5 Introduction 2 5.1 Possible solutions . 2 5.2 Communication scenarios 3 6 N-ISDN (64 kbit/s based) interface requirements 3 6.1
15、Scenario A 4 6.1.1 Introduction . 4 6.1.2 Emulation of the B and D channels . 6 6.1.3 Emulation of the basic and primary rate access 6 6.2 Scenario B 7 6.3 Interworking requirements for access signalling. . 8 6.4 Interworking requirements for network signalling . 8 7 Interworking of release 1 and re
16、lease 2 9 7.1 Requirements for B-ISDN signalling protocol evolution. 9 7.2 Scenarios for interworking . 9 7.2.1 7.2.2 7.2.3 7.2.4 Scenario A - Communication between a release 1 exchangehenninal and Scenario B - Communication between two release 2 exchangehenninal in Scenario C - Communication betwee
17、n two release 2 exchangehenninal in Scenario D - Communication via a version 1 transit node for release 2/3 a release 2/3 exchangehenninal case of a release 1 service request . case of a release 2/3 service request 9 10 10 10 11 services. . 7.3 Support of release 2 services by using release 1 equipm
18、ent . Supplement 11 to ITU-T Q-Series Recommendations TECHNICAL REPORT TRQ.201 O: B-ISDN SIGNALLING INTERWORKING REQUIREMENTS 1 Scope This Supplement specifies the general aspects for the development of B-ISDN signalling requirements. The general aspects are defined in terms of signalling interworki
19、ng requirements. 2 Refer en ces The following Technical Reports and other references contain provisions which, through reference in this text, constitute provisions of this Supplement. At the time of publication, the editions indicated were valid. All supplements and other references are subject to
20、revision; all users of this Supplement are therefore encouraged to investigate the possibility of applying the most recent edition of the supplements and other references listed below. A list of the currently valid ITU-T Recommendations and supplements is regularly published. ITU-T Q-series Recommen
21、dations - Supplement 7 (1 999), Technical Report TRQ.2001: General aspects for the development of uned signalling requirements. ITU-T Q-series Recommendations - Supplement 10 (1999): Technical Report TRQ.2002: Information Flow Elements. ITU-T Recommendation F.811 (1 996), Broadband connection-orient
22、ed bearer service. ITU-T Recommendation 4.921 (1 997), ISDN user-network interface - Data link layer specijcation. ITU-T Recommendation 4.93 1 (1 998), ISDN user-network interface layer 3 speczjcation for basic call control. ITU-T Recommendation 1.43 1 (1993), Primary rate user-network interface - L
23、ayer 1 specijcation . ITU-T Recommendation 1.430 (1 999, Basic user-network interface - Layer I specijkation. CCITT Recommendation Q.767 (1991), Application of the ISDN user part of CCITT Signalling System No. 7 for international ISDN interconnections. Definitions This Supplement defines the followi
24、ng term: 3.1 between one call party end point and its serving node. call: An end-to-end communications service between two or more call party end points, or 4 Abbreviations This Supplement uses the following abbreviations: AAL ATM Adaptation Layer ATM Asynchronous Transfer Mode BC Bearer Control STD
25、eITU-T RECMN SERIES Q SUPP ll-ENGL le199 9 4852593 Ob83897 138 9 B-ISDN B-NT2 B-TE Broadband Terminal Equipment cc Call Control ET Exchange Termination ISDN Integrated Services Digital Network ISUP Integrated Services User Part IWU Interworking Unit MTP Message Transfer Part NA Network Adaptor “I Ne
26、twork node interface NT2 Network Termination Type 2 N-TE Narrowband Terminal Equipment PSTN Public Switched Telephone Network QOS Quality Of Service TE Terminal Equipment TE1 Terminal Equipment Identifier TEX Transit Exchange UNI User-Network Interface Broadband Integrated Services Digital Network B
27、roadband Network Termination type 2 5 Introduction When a new or enhanced signalling protocol is introduced into a network, it is important that existing operations are not impaired. It is important that any signalling requirements for B-ISDN should take into account the need to maintain the stabili
28、ty of existing standards. 5.1 Possible solutions Since the target solution is longer term, the probability is that a completely stand-alone network will support B-ISDN. However, two possible options can be applied (the selection will depend on the needs of a network operator), as follows: i) ii) a s
29、tand-alone overlay network. With the second option, contact with the existing network) will be through clearly identified interworking nodes and there will be a requirement to clearly SpeciQ the interworking mechanism to be employed. Impact on existing operations will be minimal and policing at thos
30、e nodes common to both networks to ensure no “overflowing“ of signalling should suffice. The solution itself being new should not impact on the existing standard. The first option, however, will present greater problems in minimising the impact of an enhanced protocol. To avoid abortive processing a
31、nd signalling, “signalling route“ policing will be required, i.e. B-ISDN signalling will only be allowed on to the appropriate routes. In addition, the enhancements to the existing protocol and procedures should be in accordance with the rules for compatibility contained in current Recommendations.
32、integration with the existing networks; or STDmITU-T RECMN SERIES Q SUPP LL-ENGL 1999 4862593 0683898 074 II In the last case, not only should existing operations be protected but the standards will also need to be secured form any possible destabilisation, as a result of enhancement. This can be ac
33、hieved by using a similar approach to producing the enhancement as that employed for the existing standard. As stated above, any enhancement produced should align with the specified compatibility requirements for procedures, messages, etc. for the standard being enhanced. Protection of existing stan
34、dards, compatibility and ease of interworking are important requirements of any signalling solution produced for B-ISDN. 5.2 Communication scenarios Considering the interworking configuration of ISDN having both 64 kbit/s based ISDN capabilities and broadband capabilities, the communication scenario
35、s are identified as shown in Figure 5-1. These scenarios also apply to any two networks with different signalling protocols, and are as follows: scenario I is an inter-exchange scenario between B-ISDN and 64 kbit/s based ISDN; scenario II is a network concatenation interworking scenario, but the int
36、erfaces and services in scenario III, the service capabilities provided between broadband user access points are in scenario IV, end-to-end access has broadband capabilities and can provide the services are the same as those which are currently provided by 64 kbit/s based ISDN; restricted to 64 kbit
37、/s based ISDN capabilities; and currently provided by 64 kbit/s based ISDN. The 64 kbit/s based ISDN services provided by this scenario are similar to those provided by scenario I and III. Figure 5-1 - Communication scenarios between B-ISDN and 64 kbis based ISDN 6 From the view of the B-ISDN user,
38、64 kbits based ISDN services are accessible to them without any restriction. In order to fulfil this requirement, two possible interface scenarios may be considered: Scenario A: To provide access to 64 kbits based ISDN through a B-ISDN (Figure 6-1); or Scenario B: To integrate all 64 kbit/s based IS
39、DN services in B-ISDN with a broadband signalling protocol (see Figure 6-4). N-ISDN (64 kbis based) interface requirements STD-ITU-T RECMN SERIES d SUPP LI-ENGL 1999 48b259L 0683897 TOO W 6.1 Scenario A 6.1.1 Introduction In this scenario a transparent ATM connection, either permanent, semi-pemanent
40、 or on-demand is used. The corresponding bearer service is broadband connection-oriented bearer service-A as described in Recommendation F.811 3. The introduction of ATM in B-ISDN should allow the functionalities operated in the existing ISDN to be re-used. It should be possible to allow the N-TES v
41、ia B-ISDN premises to get access to ISDN services. One possible arrangement may require the B-ISDN to provide transparent connections to connect these This scenario may have two possible cases: Case 1 : Emulation of the B and D channels of basic and primary rate access. Case 2: Emulation of the basi
42、c and primary rate access. N-TES to an IWU. N-TE 64 kbiVs based N-TE B-NT2 NA Ti110926-00 S Figure 6-1 - Scenario A This scenario, as depicted in Figures 6-2 and 6-3, may have two possible cases. TE B-NT2 NA case 1.a): 4.9311 k 4.93 1 TE ISUPI 0.9311 b AAL C.O. data AAL AAL 4 ATM ATM ATM II III I TB
43、 Signalling (Note) S II I T 4 b AAL AAL - ATM ATM ATM Type1 User information AAL 4 + AAL ATM ATM ATM Ill III 1 1 I II S case 1.b): III I TB T User information transfer (interworking in the U-plane) 4.93 I I ISUPI 4.93 1 I Q.9311Q.921 Q.921 -Q.921 - AAL 4 b AAL Type 1 ATM ATM ATM II III I II Il I T T
44、B Signalling (Note) S NOTE - In this scenario C-Plane is not used for signalling for call establishment within BISDN. The signalling protocol will be transferred through ATM connection as user information. Figure 6-2 - Example of internorking Scenario A 6.1.2 a) b) TE B-NT2 - STD.ITU-T RECMN SERIES
45、Q SUPP U-ENGL wi? m BZVL OWIOL 479 rn Emulation of the B and D channels B-channels supported by AAL type 1 ; D-channel supported by ”connection-oriented data AAL”. B-channels supported by AAL type 1; D-channel supported by AAL type I. NA TE A B-NT2 is used to connect the TES (64 kbits TES) to the B-
46、ISDN. At the physical layer activation of the TES, one permanent connection (semi-permanent or on-demand ATM connection) will link the TES to the NA. The B-NT2 will packetizerdepacketize information fiodto D channel in an ATM cell flow. The data link connection will be established between the TES an
47、d the NA and the Recommendation 4.921 4 TE1 procedures may then take place under the control of the NA. The NA may then play the role of the NT2 or ET. Following that step the circuit connection control protocol of Recommendation Q.93 1 5 may take place. During the circuit connection establishment p
48、hase, the allocation of the B channels will result in dynamic establishment and allocation of ATM connections between the B-NT2 and the NA. 4 1.431 1.430 b b AAL AAL 4 ATM ATM ATM Type1 6.1.3 In this scheme the B-NT2 will have a very generic function which is reduced to the circuit emulation functio
49、n foreseen in AAL class A. The 64 kbit/s S interface will be prolonged fiom the B-NT2 to the NA. In this scenario the B-ISDN is transparent to the 64 kbit/s ISDN circuit-switched call control. The NA is seen from the B-ISDN as a specialized service provider (server for 64 kbit/s ISDN services access). It is viewed as the NT2 or the ET fiom the 64 kbit/s based ISDN network. Two subcases may be distinguished: a) b) Emulation of the basic and primary rate access ITU-T Recommendation 1.431 6 emulation: in this case the whol
