1、 STD-ITU-T RECMN a.2961=3-ENGL 1997 = 4862571 0646900 621 INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Q.2961.3 SERIES Q: SWITCHING AND SIGNALLING Broadband ISDN - B-ISDN application protocols for access signal I i ng (O 9/97) Digital Subscriber Signall
2、ing System No. 2 - Additional traffic parameters: Signalling capabilities to support traffic parameters for the available bit rate (ABR) ATM transfer capability ITU-T Recommendation Q.2961.3 (Previously CCITT Recommendation) ITU-T Q-SERIES RECOMMENDATIONS SWITCHING AND SIGNALLING SIGNALLING IN THE I
3、NTERNATIONAL WAL SERVICE INTERNATIONAL AUTOMATIC AND SEMI-AUTOMATIC WORKING FUNCTIONS AND INFORMATION FLOWS FOR SERVICES IN THE ISDN CLAUSES APPLICABLE TO ITU-T STANDARD SYSTEMS SPECIFICATIONS OF SIGNALLING SYSTEMS No. 4 AND No. 5 SPECIFICATIONS OF SIGNALLING SYSTEM No. 6 SPECIFICATIONS OF SIGNALLIN
4、G 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 LAND MOBILE NETWORK INTERWORKING WITH SATELLITE MOBILE SYSTEMS INTELLIGENT NETWORK BROADBAND ISDN Genera
5、l aspects Signalling ATM adaptation layer (SAAL) Signalling network protocols Q.l-Q.3 Q.4-Q.59 Q.60-Q.99 Q. 100-Q. 119 Q. 1204.249 Q.250-Q.309 Q.310-Q.399 Q.400-Q.499 Q.500-Q.599 Q.600+.699 4.7004.849 Q.85-Q.999 Q.lOOO-Q. 1099 Q. llOO-Q.1199 Q.12OO-Q.1999 Q.200O-Q.2999 Q.2000-Q.2099 4.2 1004.2199 Q.
6、2200-Q.2299 4.2600-4.2699 Common aspects of B-ISDN application protocols for access signalling anL netwoi signalling and interworking B-ISDN application protocols for the network signalling 0.2700-0.2899 _- - - - - B-ISDN application protocols for access Signalling Q.29oo-Q.2999 For further details,
7、 please refer to ITU-T List of Recommendations. ITU-T RECOMMENDATION Q.2961.3 DIGITAL SUBSCRIBER SIGNALLING SYSTEM NO. 2 - ADDITIONAL TRAFFIC PARAMETERS: SIGNALLING CAPABILITIES TO SUPPORT TRAFFIC PARAMETERS FOR THE AVAILABLE BIT RATE (ABR) ATM TRANSFER CAPABILITY Summary Available Bit Rate (ABR) re
8、fers to an ATM transfer capability where the limiting ATM layer transfer characteristics provided by the network may change subsequent to connection establishment. It is expected that a user which adapts its traffic to the changing ATM layer transfer characteristics will experience a low cell loss r
9、atio. Recommendation 4.2961 covers the support of additional traffic parameters for the B-ISDN at the TB reference point or coincident SB and TB reference point as defined in Recommendation 1.413 by means of the DSS 2. This Recommendation defines the DSS 2 protocol procedures, formats and functions
10、needed to support the ABR ATM transfer capability as defined in Recommendation 1.371. This Recommendation includes the use of the DSS 2 signalling procedures for the negotiation of Minimum Cell Rate (MCR) during call establishment. ABR precludes use of DSS 2 signalling procedures for the modificatio
11、n of traffic parameters during the active phase of the call. Source ITU-T Recommendation 4.2961.3 was prepared by ITU-T Study Group 11 (1997-2000) and was approved under the WTSC Resolution No. 1 procedure on thel2th of September 1997. Recommendation Q.2961.3 (09/97) 1 STD-ITU-T RECMN Q.29bL.3-ENGL
12、1997 4Bb2591 Ob4b903 330 FOREWORD IT (International Telecommunication Union) is the United Nations Specialized Agency in the field of telecommuni- cations. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent orgar) of the ITU. The ITU-T is responsible for studying technical, oper
13、ating 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 for study by the IT-T Study Groups which, in their
14、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 IT-Ts purview, the necessary standards are prepared on a collaborative
15、basis with IS0 and IEC. 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 implementat
16、ion of this Recommendation 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.
17、As of the date of approval 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
18、 urged to consult the TSB patent database. O ITU 1998 Ali 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 from the ITU. 11 Recommendation 4.2961.3 (09
19、/9) . . . STD-ITU-T RECMN Q.2961.3-ENGL 3997 4862593 O646904 277 CONTENTS 1 2 3 4 5 6 7 8 9 11 12 13 14 Scope References Definitions . I Abbreviations . Description . Operational requirements . 6.1 Provision and withdrawal . 6.2 Requirements at the originating network side 6.3 Requirements at the te
20、rminating network side Primitive and state definitions 7.1 Primitive definitions . 7.2 Call states Coding requirements 8.1 Messages . 8.2 Information elements Signalling procedures at the coincident SB and TB reference point . 9.1 CalVconnection establishment at the originating interface . 9.2 CalYc
21、onnection establishment at the destination interface . 9.3 Handling of specific error conditions . 10 Signalling procedures at the TB reference point for interworking with private B-ISDNs Interaction with entities which do not support the ABR ATM transfer capability . Interactions with supplementary
22、 services . Parameters and timers Interworking with other networks 11.2 Interworking with N-ISDN . 11.1 Dynamic description (SDLs) Annex A . Valid combinations of traffic-related parameters for the support of ABR transfer capability . Annex B - Handling of the cumulative RM fixed round-trip time par
23、ameter . B.l General B.2 Handling of the cumulative RM fixed round-trip time parameter Page 1 1 2 2 2 3 3 3 3 3 3 3 3 3 4 7 7 10 10 10 11 11 11 11 11 11 11 12 12 12 Appendix I . Instruction indicators . 13 . Recommendation 4.2961.3 (09197) 111 - Recommendation 4.2961.3 DIGITAL SUBSCRIBER SIGNALLING
24、SYSTEM NO. 2 - ADDITIONAL TRAFFIC PARAMETERS: SIGNALLING CAPABILITIES TO SUPPORT TRAFFIC PARAMETERS FOR THE AVAILABLE BIT RATE (ABR) ATM TRANSFER CAPABILITY (Geneva, 1997) 1 Scope Recommendation 4.296 1 covers the support of additional traffic parameters for the Broadband Integrated Services Digital
25、 Network (B-ISDN) at the TB reference point or coincident SB and TB reference point as defined in Recommendation 1.413 i by means of the Digital Subscriber Signalling System No. 2 (DSS 2). This Recommendation defines the DSS 2 protocol procedures, formats and functions needed to support the identifi
26、ed ATM traffic-related additional capabilities. This Recommendation is part of the DSS 2 family of Recommendations; it specifies extensions to Recommen- dation 4.293 1, and does not repeat states, information elements, messages and procedures contained therein, but only specifies extensions related
27、to additional traffic parameter indications. This Recommendation defines the additional traffic parameters required for the support of the Available Bit Rate (ABR) ATM transfer capability as defined in Recommendation 1.371 3. This Recommendation includes the use of the DSS 2 signalling procedures fo
28、r the negotiation of traffic parameter Minimum Cell Rate (MCR) during call establishment. ABR precludes use of DSS 2 signalling procedures for the modification of traffic parameters during the active phase of the call. 2 References The following ITU-T Recommendations and other references contain pro
29、visions 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 Recommendation are therefore encouraged to investigate the p
30、ossibility 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 13 ( 1993), B-ISDN user-network interface. ITU-T Recommendation 4.293 1 (1995), Digital subscr
31、iber Signalling System No. 2 - User-Network Interface (UNI) layer 3 specijcation for basic caWconnection control. ITU-T Recommendation 1.37 1 (1996), Traffic conpol and congestion control in B-ISDN. IT-T Recommendation I. 150 (1993), B-ISDN asynchronous transfer modefunctional characteristics. IT-T
32、Recommendation 4.295 1.1 (1 995) Stage 3 description for number identiJication supplementary services using B-ISDN Digital Subscriber Signalling System No. 2 (DSS 2) - Basic call: Direct-Dialling-In (DDI). ITU-T Recommendation 4.2957.1 (1995), Stage 3 description for additional information transfer
33、supplementary services using B-ISDN Digial Subscriber Signalling System No. 2 (DSS 2) - Basic call: User-lo-User Signalling (VUS). Recommendation 4.2961.3 (09/97) 1 ITU-T Recommendation Q.2961.2 (1997), Digital subscriber Signalling System No. 2 - Additional trafic parameters: Support of ATM transfe
34、r capability in the broadband bearer capability information elements. ITU-T Recommendation Q.2962 (1996), Digital subscriber Signalling System No. 2 - Connection characteristics negotiation during caWconnection establishment phase. ITU-T Recommendation Q.2963.1 (1996), Digital subscriber Signalling
35、System No. 2 - Connection mod$- cation: Peak cell rate modification by the connection owner. ITU-T Recommendation Q.2955.1 (1997), Stage 3 description for community of intepest supplementary services using B-ISDN Digital Subscriber Signalling System No. 2 (DSS 2): Closed User Group (CUG). Definition
36、s The definitions of Annex J/Q.2931 2 apply. In addition, this Recommendation defines the following terms: 3.1 Cell Loss Prioriy (CLP): A one-bit indication in the header of each ATM cell. This bit indication may be used by the user to generate traffic flows with two different cell loss ratio object
37、ives, as defined in Recommendation 1.150 4. 3.2 connection at the B-ISDN UNI (see Recommendation 1.371 3). traffic contract: A traffic contract specifies the negotiated traffic and QOS characteristics of an ATM layer 3.3 congested conditions. A list of traffic control functions is given in Recommend
38、ation 1.371. 3 traffic control: Traffic control at the ATM layer refers to the set of actions taken by the network to avoid 3.4 or qualitative. Traffic parameters may for example describe peak cell rate, minimum cell rate, etc. traffic parameters: A traffic parameter is a specification of a particul
39、ar traffic aspect. It may be quantitative 4 Abbreviations The abbreviations of Annex J/Q.293 1 2 apply. This Recommendation also uses the following abbreviations: ABR CLR FRT ICR MCR PCR RDF RIF RM TBE 5 Available Bit Rate Cell Loss Ratio Cumulative RM Fixed Round-trip Time Initial Cell Rate Minimum
40、 Cell Rate Peak Cell Rate Rate Decrease Factor Rate Increase Factor ATM Resource Management Cell ABR Transient Buffer Exposure Description This Recommendation specifies the signalling of additional traffic parameters beyond the ones already specified by Recommendation Q.2931 Z. In particular, the su
41、pport of traffic parameters for ABR is specified. 2 Recommendation 4.2961.3 (09/97) ABR is an ATM transfer capability where the limiting ATM layer transfer characteristics provided by the network may change subsequent to connection establishment. It is expected that a user that adapts its traffic to
42、 the changing ATM layer transfer characteristics will experience a low Cell Loss Ratio (CLR). The calling user shall specify a maximum required bandwidth Peak Cell Rate (PCR) to the network on establishment of connection for which it requests the use of the ABR ATM transfer capability. The maximum r
43、equired bandwidth is negotiated between user and network and between user and user at connection establishment. A minimum available bandwidth also referred to as the Minimum Cell Rate (MCR) shall be specified on a per-connection basis. The value of the PCR and of the MCR can be different for each di
44、rection of a bidirectional connection. Traffic parameter modification using procedures of Recommendation Q.2963.1 9 are precluded during the active phase of the call. 6 Operational requirements 6.1 Provision and withdrawal The additional traffic indications may be included in signalling messages by
45、the user as specified in this Recommenda- tion provided that a prior arrangement is made with the service provider. 6.2 Requirements at the originating network side The procedures according to clause 9 shall apply. 6.3 The procedures according to clause 9 shall apply. Requirements at the terminating
46、 network side 7 Primitive and state definitions 7.1 Primitive definitions Clause 8/Q.293 1 shall apply. 7.2 Call states See clause 2/Q.293 1. No additional call states are defined. 8 Coding requirements 8.1 Messages No additional messages are specified beyond the ones of 3. UQ.293 1. The existing Q.
47、293 1 messages that have had their contents modified to support the additional traffic parameters are described below. 8.1.1 Connect This message is sent by the called user to the network and by the network to the calling user to indicate call acceptance by the called user. See Table 1 for additions
48、 to the structure of this message shown in Table 3-2/Q.293 1. Recommendation 4.2961.3 (09/97) 3 STD=ITU-T RECHN Q.2963.3-ENGL 1997 4862593 064b908 912 Information element ABR setup parameters ATM traffic descriptor Reference Direction Type Length 8.2.2 Both O (Note i) 4-32 8.2.1 Both O (Note 2) 12-2
49、0 8.1.2 SETUP Information element ABR setup parameters ATM traffic descriptor Minimum acceptable ATM traffic descriptor This message is sent by the calling user to the network and by the network to the called user to indicate call establishment. See Table 2 for additions to the structure of this message shown in Table 3-19/Q.2931. Reference Direction Type Length 8.2.2 Both O (Note 1) 4-32 8.2.1 Both M (Note 2) 12-20 8.2.4 Both O (Note 3) 4-12 Table 2/Q.2961.3 - SETUP message additional content NOTE 1 - Mandatory when the