1、INTERNATIONAL TELECOMMUNICATION UN ION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Series Q Supplement 16 (1 2/1999) SERIES Q: SWITCHING AND SIGNALLING Technical Report TRQ.2140: Signalling requirements for the support of narrowband services via broadband transport technologies ITU-T Q-ser
2、ies Recommendations - supplement 16 (Formerly CCITT Recommendations) ITU-T Q-SERIES RECOMMENDATIONS SWITCHING AND SIGNALLING SIGNALLING IN THE INTERNATIONAL MANUAL SERVICE INTERNATIONAL AUTOMATIC AND SEMI-AUTOMATIC WORKING FUNCTIONS AND INFORMATION FLOWS FOR SERVICES IN THE ISDN SPECIFICATIONS OF SI
3、GNALLING SYSTEMS No. 4 AND No. 5 SPECIFICATIONS OF SIGNALLING SYSTEM No. 6 SPECIFICATIONS OF SIGNALLING SYSTEM R1 SPECIFICATIONS OF SIGNALLING SYSTEM R2 DIGITAL EXCHANGES INTERWORKING OF SIGNALLING SYSTEMS SPECIFICATIONS OF SIGNALLING SYSTEM No. 7 DIGITAL SUBSCRIBER SIGNALLING SYSTEM No. 1 PUBLIC LA
4、ND MOBILE NETWORK INTERWORKING WITH SATELLITE MOBILE SYSTEMS INTELLIGENT NETWORK CLAUSES APPLICABLE TO ITU-T STANDARD SYSTEMS SIGNALLING REQUIREMENTS AND PROTOCOLS FOR IMT-2000 BROADBAND ISDN Q. 1 -Q .3 Q .4-Q.59 Q.60-Q.99 Q. 1 OO-Q. 1 1 9 Q.120-Q.249 Q.250-Q.309 Q.310-Q.399 Q.400-Q.499 Q. 500-Q. 59
5、9 Q.600-Q.699 Q.700-Q.849 Q.850-Q.999 Q.1000-Q.1099 Q.1100-Q.1199 Q.1200-Q.1699 Q. 1 700-Q. 1 799 Q.2000-Q.2999 II - - For further details, please refer to the list of ITU-TRecomrnendations. SUPPLEMENT 16 TO ITU-T Q-SERIES RECOMMENDATIONS TECHNICAL REPORT TRQ.2140: SIGNALLING REQUIREMENTS FOR THE SU
6、PPORT OF NARROWBAND SERVICES VIA BROADBAND TRANSPORT TECHNOLOGIES Summary This Supplement to ITU-T Q-Series Recommendations is a Technical Report on the procedures, information flows and information elements needed for supporting narrowband services via broadband transport technologies. Its scope is
7、 limited to functionality of the Serving Node and the associated protocols at the call control and bearer control levels needed to provide this capability across an ATM backbone network for Capability Set 1. Source Supplement 16 to ITU-T Q-series Recommendations was prepared by ITU-T Study Group 11
8、(1 997-2000) and was approved under the WTSC Resolution 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 permanent organ of t
9、he ITU. 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, establishes t
10、he 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 1. In some areas of information technology which fall within ITU-Ts purvie
11、w, 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 ITU draws atten
12、tion 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 members or other
13、s 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, implementors are cautioned that this may not represent the l
14、atest 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 permission in writing
15、from the ITU. _ CONTENTS Page 1 1.1 1.2 1.3 1.4 2 3 3.1 3.2 4 5 5.1 5 -2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 5.10 5.1 1 5.12 5.13 5.14 5.15 5.16 5.17 Scope Service Requirements . High Level Requirements . Guidelines for protocol development . Functional Reference Model References Definitions Functional Mode
16、l Definitions . Definition of Signalling Flow Objects . Abbreviations . Requirements General . Addressing 5 2.1 Call Control . 5.2.2 BNC Control . Routing . 5.3.1 Call Control . 5.3.2 BIWF Selection Control 5.3.3 BNC Control . Symmetry of call and bearer control 5.4.1 Call Control . 5.4.2 BNC Contro
17、l . Connection configuration . Essential features of the underlying signalling transport . Independence from underlying signalling transport . Flow control Concatenation . Contention resolution . Error reporting Unrecoverable failures Forward and backward compatibility . Separation between signallin
18、g controls Performance Requirements Codec Negotiation Codec Modification 1 2 2 2 8 8 8 8 8 9 9 9 9 9 9 9 9 9 9 9 10 10 10 10 10 10 11 11 Il 11 Page 6 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 6.10 6.1 1 7 8 8.1 8.2 8.3 Signalling Procedures . 11 Successful Call Set-up. . 11 6.1.1 Call Establishment . 11 6
19、.1.2 Bearer establishment . 11 Unsuccessful Set-up . 11 Error Handling 12 Echo Control Procedure 12 Blocking and unblocking 12 Call Automatic Repeat attempts. 12 Dual Seizure . 12 Reset . 12 Support of Codec Negotiation 12 Support of Codec Modification 12 General Signalling Transport Requirements 12
20、 Release of a Successful Call . 11 Backbone Network Signalling Flows . Successful Backbone Call and Backbone Network Connection Establishment 8.1.1 Establishment of a Backbone Network Connection 8.1.2 Establishment of a Backbone Network Connection with Transit Serving Node 8.1.3 Reuse of an Idle Bac
21、kbone Network Connection . 8.1.4 Establishment of a Backbone Network Connection with Codec Negotiation 8.1.5 Establishment of a Backbone Network Connection with Codec Negotiation and Transit Serving Node 8.1.6 Forward Connection Set-up with Call Mediation Node 8.1.7 Codec Modification Signalling Req
22、uirement Flows . 13 15 15 27 44 53 65 80 88 Call Release .: 90 8.2.1 Call Release . 90 8.2.2 Call Release with Mediation Node 92 8.2.3 Call Release with Transit Serving Node . 95 Backbone Network Connection Release 97 Annex A - Capability Set 1 Services and Functions . 1 O0 Supplement 16 to Q-series
23、 Recommendations TECHNICAL REPORT TRQ.2140: SIGNALLING REQUIREMENTS FOR THE SUPPORT OF NARROWBAND SERVICES VIA BROADBAND TRANSPORT TECHNOLOGIES 1 Scope This Supplement provides requirements for the support of narrowband services via broadband transport technologies. Its scope is limited to functiona
24、lity of the Serving Node (SN) and the associated protocols at the call control and bearer control levels needed to provide this capability across an ATM backbone network for Capability Set 1 (CS 1). 1.1 Service Requirements In principle, it is required that all signalling related features, functions
25、, and services currently supported in the TDM-based trunlung network using Narrowband-ISUP (N-ISUP), continue to be supported when replaced by an ATM-based trunking network. ISDN User Part Capabilities, both national and international, as listed in Tables 1 and 2 in clause 3lQ.761, “Signalling Syste
26、m No. 7 - ISDN User Part functional description“ are to be supported in capability set 1. Annex A contains a detailed list of the required narrowband services to be included into capability set 1. High Level Requirements Provide a means of supporting narrowband ISDN services across a broadband backb
27、one network without impacting the interfaces to the existing N-ISDN network and end-to-end services. Provide functional separation of call and bearer signalling protocols with binding information carried by both protocols allowing separate independent establishment of calls and bearers within the br
28、oadband backbone network. Binding information allows the coordination of these independent protocol streams to be correlated at the end points of this ATM backbone network. In CS 1, the call control signalling protocol is based on N-ISUP signalling and the different bearer technology based control s
29、ignalling protocols are supported (e.g. DSS2 for AAL type 1 and AAL type 2 signalling protocol). IP bearer transport will be considered in later capability sets. The call control signalling protocol should not be aware of the actual bearer transport being employed. The binding information is used to
30、 reference the bearer. Functions associated with bearers, such as blocking and echo control, should be handled by the bearer control. Signalling of echo control shall be performed by the call control signalling protocol. The signalling between the ISDN networks and the broadband backbone network is
31、intenvorked within an Intermediate Service Node (ISN) that will: terminate incoming/outgoing signalling; generate and terminate backbone call and bearer signalling; and map the incoming/outgoing bearer transport technology used between the ISDN networks and the broadband backbone network to the bear
32、er transport technology used within the broadband backbone network. 1.3 Guidelines for protocol development Even though this Supplements scope is signalling requirements, this subclause is provided as an understanding of the scope of signalling capabilities requirements that should be developed. 1)
33、The CS 1 services are the ITU-T defined narrowband ISDN services as supported by the 2000 version of ISUP (see Annex A). 2) Only point-to-point bidirectional bearer services will be considered in call control signalling capability set 1 (CS 1). 3) The modifications to the existing N-ISUP procedures
34、should be limited to those necessary to allow for the separation of call control and bearer. Services and functions not related to the bearer transport should not be impacted. The call control protocol at a minimum should be able to be transport on MTP layer 3, 1992 version (or later). In addition,
35、the call control protocol may be transported on MTP layer 3b, 1996 version (or later). 5) Maximum end-to-end Set-up delay should not be exceeded as defined for current narrowband networks. 6) The call control and bearer control protocols should be designed to operated over multiple carrier network d
36、omains. 7) The protocols used for the support of this capability should not impact the interfaces to the existing ISDN network. 4) 1.4 Functional Reference Model Figure 1-1 shows the composition of the functional reference model. Refer to clause 3 for the definition of each of the functional entitie
37、s. The signalling network will be used for the transport of the call control signalling. The interface from the existing network will be N-ISUP. 2 References The following Technical Reports and other references contain provisions which, through reference in this text, constitute provisions of this S
38、upplement. At the time of publication, the editions indicated were valid. All supplements and other references are subject to 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 lis
39、ted below. A list of the currently valid ITU-T Recommendations and supplements is regularly published. - - ITU-T Recommendation 4,115 (1997), Logic for the control of echo control devices. ITU-T Recommendation 4.701 (1993), Functional description of the Message Transfer Part (MTP) of Signalling Syst
40、em No. 7. - CCITT Recommendation Q.702 (1 988), Signalling data link. - ITU-T Recommendation 4.703 (1 996), Signalling link. - ITU-T Recommendation 4.704 (1 996), Signalling network functions and messages. - ITU-T Recommendation 4.706 (1 993), Message transfer part signalling performance. - ITU-T Re
41、commendation Q.761 (1999), Signalling System No. 7 - ISDN user part functional description. TTU-T Recommendation 4.762 (1997), General function of messages and signals of the ISDN user part of Signalling System No. 7. - - ITU-T Recommendation 4.763 (1997), Signalling System No. 7 - ISDN user part fo
42、rmats and codes. ITU-T Recommendation 4.764 (1 999), Signalling System No. 7 - ISDN user part signalling procedures. ITU-T Recommendation 4.765 (1998), Signalling System No. 7 - Application transport mechanism. ITU-T Recommendation 4.766 (1 993), Performance objectives in the integrated services dig
43、ital network application. ITU-T Recommendation 4.2 140 (1 995), B-ISDN ATM adaptation layer - Service specific coordination function for signalling at the network node interface (SSCF AT NNO. ITU-T Recommendation 4.22 1 O (1 996), Message transfer part level 3 functions and messages using the servic
44、es of ITU-T Recommendation Q.2140. - - - - - -._ I -._ ._ I -. I . . . . .-/- I I I I I I _- I I I I I I I I I I I v)I . c, 21 .o I I u1 r,I m I l I I I I I I I I I I / / 3 Definitions 3.1 Functional Model Definitions Definitions of the items contained in the composite functional model are as follow
45、s: 3.1.1 Backbone Network Connection (BNC): Represents the edge-to-edge transport connection within the backbone network, consisting of one or more Backbone Network Connection Links (BNCL). The Backbone Network Connection represents a segment of the end-to-end Network Bearer Connection (NBC). 3.1.2
46、Backbone Network Connection Link (BNCL): Represents the transport facility between two adjacent backbone network entities containing a bearer control function. 3.1.3 Bearer Control Function (BCF): Note that four types of BCFs are illustrated in the above functional model; BCF-G, BCF-N, BCF-R and BCF
47、-T. - The Bearer Control Nodal Function (BCF-G) provides the control of the bearer switching function, the communication capability with its associated Call Service Function (CSF-G), and the signalling capability necessary to establish and release of the backbone network connection. The Bearer Contr
48、ol Nodal Function (BCF-N) provides the control of the bearer switching function, the communication capability with its associated call service function (CSF), and the signalling capability necessary to establish and release of the backbone network connection to its peer (BCF-N). The Bearer Control R
49、elay Function (BCF-R) provides the control of the bearer switching function and relays the bearer control signalling requests to next BCF in order to complete the edge-to-edge backbone network connection. The Bearer Control Nodal Function (BCF-T) provides the control of the bearer switching function, the communication capability with its associated Call Service Function (CSF-T), and the signalling capability necessary to establish and release of the backbone network connection. 3.1.4 Bearer Control Segment (BCS): Represents the signalling relationship between two a
