1、INTERNATIONAL TELECOMMUNICATION UNIONITU-T Series QTELECOMMUNICATIONSTANDARDIZATION SECTOROF ITUSupplement 35(12/2000)SERIES Q: SWITCHING AND SIGNALLINGTechnical report TRQ.2500: Signallingrequirements for the support of the call bearercontrol interface (CS-1)ITU-T Q-series Recommendations Supplemen
2、t 35(Formerly CCITT Recommendations)ITU-T Q-SERIES RECOMMENDATIONSSWITCHING AND SIGNALLINGSIGNALLING IN THE INTERNATIONAL MANUAL SERVICE Q.1Q.3INTERNATIONAL AUTOMATIC AND SEMI-AUTOMATIC WORKING Q.4Q.59FUNCTIONS AND INFORMATION FLOWS FOR SERVICES IN THE ISDN Q.60Q.99CLAUSES APPLICABLE TO ITU-T STANDA
3、RD SYSTEMS Q.100Q.119SPECIFICATIONS OF SIGNALLING SYSTEMS No. 4 AND No. 5 Q.120Q.249SPECIFICATIONS OF SIGNALLING SYSTEM No. 6 Q.250Q.309SPECIFICATIONS OF SIGNALLING SYSTEM R1 Q.310Q.399SPECIFICATIONS OF SIGNALLING SYSTEM R2 Q.400Q.499DIGITAL EXCHANGES Q.500Q.599INTERWORKING OF SIGNALLING SYSTEMS Q.6
4、00Q.699SPECIFICATIONS OF SIGNALLING SYSTEM No. 7 Q.700Q.799Q3 INTERFACE Q.800Q.849DIGITAL SUBSCRIBER SIGNALLING SYSTEM No. 1 Q.850Q.999PUBLIC LAND MOBILE NETWORK Q.1000Q.1099INTERWORKING WITH SATELLITE MOBILE SYSTEMS Q.1100Q.1199INTELLIGENT NETWORK Q.1200Q.1699SIGNALLING REQUIREMENTS AND PROTOCOLS F
5、OR IMT-2000 Q.1700Q.1799BROADBAND ISDN Q.2000Q.2999For further details, please refer to the list of ITU-T Recommendations.Q series Supplement 35 (12/2000) iSupplement 35 to ITU-T Q-series RecommendationsTechnical report TRQ.2500: Signalling requirements for the supportof the call bearer control inte
6、rface (CS-1)SummaryThis Supplement specifies the signalling requirements for the support of the BICC Call BearerControl Interface (CS-1).SourceSupplement 35 to ITU-T Q-series Recommendations was prepared by ITU-T Study Group 11(2001-2004) and approved under the WTSA Resolution 5 procedure on 6 Decem
7、ber 2000.ii Q series Supplement 35 (12/2000)FOREWORDThe International Telecommunication Union (ITU) is the United Nations specialized agency in the field oftelecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ ofITU. ITU-T is responsible for studying techn
8、ical, operating and tariff questions and issuing Recommendationson them with a view to standardizing telecommunications on a worldwide basis.The World Telecommunication Standardization Assembly (WTSA), which meets every four years,establishes the topics for study by the ITU-T study groups which, in
9、turn, produce Recommendations on thesetopics.The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1.In some areas of information technology which fall within ITU-Ts purview, the necessary standards areprepared on a collaborative basis with ISO and IEC.NOTEIn
10、 this publication, the expression “Administration“ is used for conciseness to indicate both atelecommunication administration and a recognized operating agency.INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this publication may involve theu
11、se of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity orapplicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside ofthe publication development process.As of the date of approval of this publication, ITU ha
12、d not received notice of intellectual property, protectedby patents, which may be required to implement this publication. However, implementors are cautioned thatthis may not represent the latest information and are therefore strongly urged to consult the TSB patentdatabase. ITU 2001All rights reser
13、ved. 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 ITU.Q series Supplement 35 (12/2000) iiiCONTENTSPage1 Scope . 12 References 13 Bibliography. 24 Abbreviations
14、. 25 Guidelines for protocol development 36 Object Reference Model. 37 Definitions 47.1 Object and Call Model Definitions . 47.2 Call Model . 57.3 Requests and Responses . 77.3.1 Definition of Requests and Responses 87.4 Definition of Signalling Flow Objects. 107.4.1 Nomenclature 107.4.2 Signalling
15、Request and Response Primitives 107.4.3 Signalling Objects 128 Signalling Procedures between the CSF and the BIWF (CBC interface) . 168.1 Successful Establishment 178.1.1 Prepare_BNC_Notify. 178.1.2 Establish_BNC_Notify 208.1.3 Reserve_BNC 238.1.4 Cut_Through . 248.1.5 Modification of Bearer Charact
16、eristics. 288.1.6 Tunnel . 348.2 Reuse of idle Bearers 368.2.1 Establish BNC . 368.2.2 Reuse_IDLE 378.3 Bearer Topology. 388.3.1 Isolate 388.3.2 Join 398.3.3 Change Connection Topology 408.4 Echo Canceller Control. 428.4.1 Echo Canceller 428.5 Unsuccessful BNC Establishment. 438.5.1 Unsuccessful BNC
17、 Establishment with notification on BNC establishment 438.6 Bearer Initiated Release 45iv Q series Supplement 35 (12/2000)Page8.7 Media Content Insertion . 478.7.1 Insert Tone 478.7.2 Insert Digit 498.7.3 Insert Announcement. 518.8 Media Content Detection 548.8.1 Detect Digit . 548.9 Cut BNC 558.9.1
18、 Release 568.10 General Procedures. 578.10.1 BIWF Service Changes 578.10.2 CCU Service Change . 668.10.3 BIWF/Termination Unavailable. 708.10.4 Audit of BIWF Service Capabilities. 719 Outage and Recovery 759.1 CCU Initiated . 759.1.1 CCU outage. 759.1.2 CCU Recovery 759.2 BIWF Initiated . 759.2.1 BI
19、WF outage . 759.2.2 BIWF RECOVERY. 75Q series Supplement 35 (12/2000) 1Supplement 35 to ITU-T Q-series RecommendationsTechnical report TRQ.2500: Signalling requirements for the supportof the call bearer control interface (CS-1)1ScopeThis Supplement provides requirements for the support of the Call B
20、earer Control Interface. Itsscope is limited to the interface between the CSF and the BIWF and the requirements to ensure thatthe associated protocols at the call control and bearer control levels can provide functionality acrossan ATM or IP networks for BICC Capability Set 2 (CS-2).T11112980-01CSFB
21、CFBIWFCCUAccess Half/Network HalfScope of SupplementLocalSignallingTerminationLocalBearerTerminationLocalSignallingTerminationLocalBearerTerminationBICCNetwork HalfFigure 1 Scope of SupplementThe main body of the recommendation details the requirements for the BICC Network Half of theCBC interface.
22、Requirements for the Access Half and Non-BICC Network Half of the interface arecontained in associated annexes.2 References1 ITU-T H.248 (2000), Gateway control protocol.2 Q series Supplement 35 (12/2000)3 Bibliography2 ITU-T Q-series Supplement 32 (2000), Technical report TRQ.2141.1: Signallingrequ
23、irements for the support of narrowband services via Broadband TransportTechnologies, CS-2 Signalling Flows.3 ITU-T Q-series Supplement 7 (1999), Technical report TRQ.2001: General aspects for thedevelopment of unified signalling requirements.4 AbbreviationsThis Supplement uses the following abbrevia
24、tions:AAL ATM Adaptation LayerATM Asynchronous Transfer ModeBCF Bearer Control FunctionBCS Bearer Control SegmentBIT Bearer Information TransportBIWF Bearer Interworking FunctionBNC Backbone Network ConnectionBNCL Backbone Network Connection LinkCBC Call and Bearer ControlCCA-ID Call Control Associa
25、tion IdentifierCCU Call Control UnitCMN Call Mediation NodeCS Capability SetCSF Call Service FunctionCSM Call State Machine (O Originating / T Terminating)DTMF Dual Tone Multi FrequencyGSN Gateway Serving NodeIP Internet ProtocolISN Interface Serving NodeLP Logical PortMOD ModifyMOV MoveNOT NotifyQo
26、S Quality of ServiceSN Serving NodeSUB SubtractTDM Time Division MultiplexTMR Transmission Medium RequirementTSN Transit Serving NodeQ series Supplement 35 (12/2000) 3USI User Service Information5 Guidelines for protocol developmentEven though this Supplements scope is signalling requirements, this
27、clause is provided as guidanceas to how these Requirements may be realised in protocol development.The H.248 core protocol has been chosen as the basis for the Call Bearer Control Protocol.A Message can contain several H.248 Transactions that may contain several Commands.Several instructions/descrip
28、tors in the one command should relate to one termination.NotificationRequested should relate to an eventDescriptor/eventBufferDescriptor in ITU-TH.248.NotificationRequested could be provisioned on terminations so that any bearer event isnotified: i.e. An event called “BNC“ with parameters “establish
29、ed, rejected, modified,released“.The interaction between an event and a tone/announcement should be considered. Thisdetectionofaneventmayresultintheimmediatestoppingofasignal.6 Object Reference ModelFigure 2 shows the composition of the object reference model. Refer to 7.1 for the definition of each
30、of the functional entities.T11112990-01CBCCCACCACCA(3)(3)(2) (2)(1)(1)(4)(4)(5)(5)(5)T-CSMBT-CSMCO-CSMACSF(1)(3)(2)InternalBIWFLocal Call InstanceLogical Port-A Logical Port-CLogical Port-BContextConnectionBIWF Control PortCCU Control PortEndPoint BEndPoint CBearerSignalling(optional)BNCExternalBNCE
31、xternalTerminationC1TerminationB1TerminationA1Termination States-Null- Loop Back External Signal (loopback)- Loop Back Internal SignalStream Mode- Cut-Through Towards Context (Receive)- Cut-Through From Context (Send)- Cut-Through Both (Send / Receive)BNCExternalBearerSignalling(optional)EndPoint AI
32、nternalInternalFigure 2 CBC Object Reference Model4 Q series Supplement 35 (12/2000)7 Definitions7.1 Object and Call Model Definitions7.1.1 Call Bearer Control (CBC): Is the interface between the Call Serving Function and theBearer Control Function.7.1.2 connection: The connection is a logical entit
33、y representing the connection topology within asingle context in the BIWF. The topology of a connection can be implied by assigning streamsbetween terminations and/or through manipulation of the context topology.7.1.3 context: The context is the association between one or more terminations. The BIWF
34、 createsa context and assigns a unique context identity (contextID) to it. A context cannot exist without atleast one termination. When a context contains a single termination, this context may or may notcontain a connection. Contexts containing a connection always will be associated with a local ca
35、llinstance, while a context containing no connection will not be associated with a Local Call Instance.See 6.1/H.248 1.7.1.4 end point: An end point defines the remote call or call & bearer signalling entitycommunicating with the CSF. This entity may be requesting actions associated with a line, tru
36、nk, orspecial resource function. In the object model it defines the point terminating the Call Signalling.7.1.5 stream: A Stream specifies the parameters of a single bi-directional media stream/user dataflow and is represented by a CSM assigned StreamID. See 7.1.6/H.248 1.7.1.6 stream mode: In the o
37、bject model it describes the mode of the termination ie. Send, receive,send and receive. See 7.1.7/H.248 1.7.1.7 termination: A Termination is a logical entity in a BIWF that sources and/or sinks mediaand/or control streams. In BICC a termination sources and/or sinks a single media and/or controlstr
38、eams. A Termination is described by a number of characterizing Properties. Terminations haveunique identities (TerminationIDs). These objects can be created “On Demand“ or may beprovisioned.7.1.8 termination state: Defines the Service state of the termination, e.g. In-service, Out-of-service. In the
39、 object model it describes the mode of the termination, i.e. Null, Loop Back ExternalSignal, Loop Back Internal Signal. See Termination State 7.1.5/H.248 1 for the service state. Forthe mode of a stream, i.e. loopback, see 7.1.7/H.248 1.7.1.9 logical port: Defines a logical grouping of one or more m
40、edia terminations and one or moresignalling termination. A Logical Port may be associated with a bearer control signalling end point(indicated by reference 3).7.1.10 Call State Machine (CSM): Defines a CSF control entity that terminates call or call &bearer peer to peer signalling. The prefix “O“ or
41、 “T“ represents the interrelationship of CSMs withinthe Local Call Instance. The “O“ represents the control entity receiving an external service request,while the “T“ is the control entity forwarding the request to another CSF.7.1.11 local call instance: Defines the call control scope within a Servi
42、ng Node. A Local CallInstance may have ZERO or more Contexts within its scope. The CSF creates and deletes local callinstances. When a Local Call Instance is destroyed, each BIWF will place the termination within theLocal Call Instance scope, into a NULL context or delete the termination.7.1.12 CCU
43、control port: Defines the signalling port associated with the CSF which is used tointeract with the BIWF over the CBC Interface. This object has a unique address within the networkservice supplier domain.7.1.13 BIWF control port: Defines the signalling port associated with the BIWF which is used toi
44、nteract with the CCU over the CBC interface. This object has a unique address within the networkservice supplier domain.Q series Supplement 35 (12/2000) 57.1.14 Call Control Association (CCA): Defines the peer to peer signalling association betweenCall, and Call & Bearer state machines located in di
45、fferent physical entities.7.1.15 Backbone Network Connection (BNC): Represents the edge to edge transport connectionwithin 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 BearerCon
46、nection (NBC).7.2 Call ModelThe Call model for use in describing the signalling requirements describes the logical entities, orobjects, within the BIWF that can be controlled by the CSF. The main abstractions used in the callmodel are local call instances, contexts, terminations and streams. Figure
47、3 shows the MultipleBIWF Call Model. A Local Call instance can span several BIWFs. Each BIWF may have multiplecontexts associated with the same Local Call Instance.T11113000-01O-CSMAT-CSMBT-CSMCLocal Call InstanceEndPoint AEndPoint BEndPoint CBIWF (X)Contexts 1, 2, 3, & 4Figure 3 Multiple BIWF Call
48、ModelFigure 4 illustrates the call model from the perspective of a single BIWF in order to further definethe interrelationships of the Local Call Reference and the Contexts within its scope.6 Q series Supplement 35 (12/2000)T11113010-01BIWF (X)BNCBNCBNCBNCBNCBNCBNCBNCBIWF-Addr=(Y):BNC-ID=(1)BIWF-Add
49、r=(Y):BNC-ID=(4)BIWF-Addr=(Z):BNC-ID=(4)BIWF-Addr=(X):BNC-ID=(4)BIWF-Addr=(Y):BNC-ID=(2)BIWF-Addr=(Y):BNC-ID=(3)BIWF-Addr=(W):BNC-ID=(4)BIWF-Addr=(X):BNC-ID=(5)Termination(f)Termination(h)Context(3)Termination(g)Context(4)Configuration 3Termination(c)Termination(d)Termination(e)Context(2)Configuration 2Termination(a)Termination(b)Context(1)Configuration 1Local Call InstanceLocal Call InstanceLocal Call InstanceConnection(2 party)Connection(Hold)Connection(3party)Connection(2 party)Figure 4 Call ModelFigure 4 represent
