1、Standard ECMA-298December 1999Standardizing Information and Communication SystemsPhone: +41 22 849.60.00 - Fax: +41 22 849.60.01 - URL: http:/www.ecma.ch - Internet: helpdeskecma.chBroadband Private IntegratedServices Network (B-PISN) -Inter-Exchange Signalling Protocol Separated Bearer Control (SBC
2、)Standard ECMA-298December 1999Standardizing Information and Communication SystemsPhone: +41 22 849.60.00 - Fax: +41 22 849.60.01 - URL: http:/www.ecma.ch - Internet: helpdeskecma.chIW ECMA-298.DOC 03-01-00 10,40Broadband Private IntegratedServices Network (B-PISN) -Inter-Exchange Signalling Protoco
3、l Separated Bearer Control (SBC)(B-QSIG-SBC)Brief HistoryThis Standard is one of a series of ECMA Standards defining services and signalling protocols applicable toBroadband Private Integrated Services Networks (B-PISNs). The series uses B-ISDN concepts as developed by ITU-Tand conforms to the frame
4、work of International Standards for Open Systems Interconnection as defined by ISO/IEC.It has been produced under ETSI work item DEN/ECMA-00160.This particular Standard specifies the signalling protocol for use at the Q reference point for separated bearer control(B-QSIG-SBC).This Standard is based
5、upon the practical experience of ECMA member companies and the results of their active andcontinuous participation in the work of ISO/IEC JTC1, ITU-T, ETSI and other international and nationalstandardization bodies. It represents a pragmatic and widely based consensus.This Standard has been adopted
6、by the ECMA General Assembly of December 1999.- i -Table of contents1Scope 12 Conformance 13 References (normative) 14 Definitions 14.1 External definitions 14.2 Other definitions 24.2.1 Connection state 24.2.2 Bearer identifier 24.2.3 Call segment 24.2.4 Call segment identifier 24.2.5 Preceding sid
7、e 24.2.6 Succeeding side 24.2.7 Side 24.2.8 Signalling AAL (SAAL) 24.2.9 Preceding PINX 24.2.10 Succeeding PINX 24.2.11 Preceding PINX with call/bearer co-ordination 24.2.12 Preceding PINX without co-ordination function 24.2.13 Succeeding PINX without co-ordination function 34.2.14 Succeeding PINX w
8、ith co-ordination function 35 List of acronyms 36 Description 36.1 Separation of call control and bearer control 36.2 Relationship to call control architecture 36.3 Capabilities supported by this Standard 46.4 General overview 47 Operational requirements 47.1 Provision and withdrawal 47.2 Requiremen
9、ts on the preceding side 57.3 Requirements on the succeeding side 58 Primitive definitions and state definitions 58.1 Primitive definitions 58.2 State definitions 58.2.1 B-QSIG connection states 59 Coding requirements 59.1 Messages 59.1.1 Modification to messages defined in ECMA-266 5- ii -9.2 Infor
10、mation elements 69.2.1 Call association 69.2.2 Bearer identifier 79.2.3 Other information elements 710 Signalling procedures at the Q reference point 710.1 Introduction 710.2 Establishment of a bearer 810.2.1 Additional procedures at a preceding side 810.2.2 Additional procedures at a succeeding sid
11、e 810.3 Procedures for joining bearer connections on adjacent call segments 910.4 Additional procedures at a Transit PINX 910.5 Clearing of a Connection 911 Interworking with other networks 1012 Interworking with supplementary services 1013 Parameter values 1014 Dynamic description SDLs 10Annex A -
12、Protocol Implementation Conformance Statement (PICS) proforma 11Annex B - Guidelines for the use of the instruction indicator 211ScopeThis Standard defines the signalling protocol for the purpose of bearer control at the Q-reference pointbetween Private Integrated Services Network Exchanges (PINXs)
13、connected together within a BroadbandPrivate Integrated Services Network (B-PISN) employing Asynchronous Transfer Mode (ATM). ThisStandard is part of the B-QSIG signalling system.This Standard specifies the essential features, procedures, and messages required for establishing, maintainingand cleari
14、ng of bearer connections to point-to-point multiconnection calls at the B-QSIG interface in afunctionally separated call and bearer control environment. Bearers are controlled independently by means ofa separated call control protocol. The separated call control protocol is assumed to be that specif
15、ied inECMA-294.This Standard is applicable to PINXs that support separated call and bearer control protocol at the Q referencepoint. The Q reference point is defined in ISO/IEC 11579-1.2 ConformanceIn order to conform to this Standard, a PINX shall satisfy the requirements identified in the Protocol
16、Implementation Conformance Statement (PICS) proforma in annex A.3 References (normative)The following standards/recommendations contain provisions, which, through reference in this text, constituteprovisions of this Standard. All standards are subject to revision, and parties to agreements based on
17、thisStandard are encouraged to investigate the possibility of applying the most recent editions of the standardsindicated below.ECMA-266 Broadband Private Integrated Services Network (B-PISN) Inter-Exchange SignallingProtocol Basic Call/Connection Control (International Standard ISO/IEC 13247)ECMA-2
18、94 Broadband Integrated Services Digital Network (B-ISDN) and Broadband PrivateIntegrated Services Network (B-PISN) - Digital Subscriber Signalling System No. two(DSS2), Broadband Inter-Exchange Signalling (B-QSIG), and Signalling System No. 7(SS7) - Call Control in a Separated Call and Bearer Contr
19、ol Environment - Part 1:Protocol SpecificationISO/IEC 11579-1 Information technology - Telecommunications and information exchange betweensystems - Private Integrated Services Network - Part 1: Reference configuration for PISNExchanges (PINX)ITU-T Rec. I.112 Vocabulary of terms for ISDNs (1993)ITU-T
20、 Rec. I.321 B-ISDN protocol reference model and its application (1991)ITU-T Rec. I.371 Traffic control and congestion control in B-ISDN (1996)ITU-T Rec. Q.9 Vocabulary of switching and signalling terms (Blue Book) (1988)4 DefinitionsFor the purposes of this Standard the following definitions apply.4
21、.1 External definitionsThis Standard uses the following terms defined in other documents:- ATM transfer capability (ATC) (ITU-T Rec. I.371)- bearer (ECMA-294)- bearer control (ECMA-294)- bearer control entity (BC entity) (ECMA-294)- 2 - call (ECMA-294)- call control (ECMA-294)- call control entity (
22、CC entity) (ECMA-294)- call control signalling service user (ECMA-294)- connection (ITU-T Rec. Q.9)- Inter-PINX Link (IPL) (ECMA-266)- private integrated services network (PISN) (ISO/IEC 11579-1)- private integrated services network exchange (PINX) (ISO/IEC 11579-1)- signalling (ITU-T Rec. I.112)- u
23、ser plane (ITU-T Rec. I.321)4.2 Other definitions4.2.1 Connection stateState for each connection which is known by the layer 3 bearer control entity.4.2.2 Bearer identifierThe identifier used to identify a bearer instance within a call segment. The value of the bearer identifieris significant betwee
24、n two adjacent call control entities. This value is unique within a call segment.4.2.3 Call segmentA part of a call located between two adjacent call control entities.4.2.4 Call segment identifierThe identifier used to identify a multiconnection call instance to which a particular bearer establishme
25、ntrequest relates between two call control entities at a given B-QSIG interface. The value of a call segmentidentifier is unique within two adjacent call control entities.4.2.5 Preceding sideWith respect to a given bearer, the side of a B-QSIG interface from which bearer establishment acrossthe inte
26、rface originates.4.2.6 Succeeding sideWith respect to a given bearer, the side (opposite to the preceding side) of a B-QSIG interface whichreceives the bearer establishment request across the interface.4.2.7 SideThe protocol control entity in a PINX at one end of an IPL.4.2.8 Signalling AAL (SAAL)Th
27、e AAL used for the bi-directional transfer of layer 3 signalling information.4.2.9 Preceding PINXPINX at the preceding side.4.2.10 Succeeding PINXPINX at the succeeding side.4.2.11 Preceding PINX with call/bearer co-ordinationPreceding PINX providing co-ordination between the call control (CC) and t
28、he bearer control (BC)entity functionality. Both CC and BC entity functionality have to be supported on this PINX.4.2.12 Preceding PINX without co-ordination functionPreceding PINX providing no co-ordination between the call control (CC) and the bearer control (BC)entity functions. Only BC entity fu
29、nctions have to be supported on this PINX.- 3 -4.2.13 Succeeding PINX without co-ordination functionSucceeding PINX providing no co-ordination between the call control (CC) and the bearer control (BC)entity functions. Only BC entity functions have to be supported on this PINX.4.2.14 Succeeding PINX
30、with co-ordination functionSucceeding PINX providing co-ordination between the call control (CC) and the bearer control (BC)entity functions. Both CC and BC entity functions have to be supported on this PINX.5 List of acronymsAAL ATM Adaptation LayerATM Asynchronous Transfer ModeBC Bearer ControlB-I
31、SDN Broadband Integrated Services Digital NetworkB-PISN Broadband Private Integrated Services NetworkCC Call ControlDSS2 Digital Subscriber Signalling System No 2IPL Inter- PINX LinkPINX Private Integrated services Network eXchangeROSE Remote Operation Service ElementSAAL Signalling ATM Adaptation L
32、ayerSBC Separated Bearer ControlSDL Specification and Description Language6 Description6.1 Separation of call control and bearer controlThe protocol specified in this Standard is applicable to an environment in which the control of a call isseparate from the control of the bearer or bearers that exi
33、st within the context of that call.In order for two users to communicate using a telecommunication service, an association, or call, isestablished between the two users. Within the context of the call, one or more bearers can be establishedfor transporting user plane information between the users. H
34、owever, bearers are not normally establisheduntil the call has been accepted by the called terminal, and therefore resources required by bearers are notoccupied unnecessarily if the call cannot be established, e.g., if the called terminal is unable to accept thecall because resources are not availab
35、le. During the lifetime of the call, bearers can be added or cleareddown as required. The call is terminated by one of the two users when there is no further need forcommunication. Termination of the call implies that all bearers (if any) are cleared down.Although for some telecommunication services
36、 a single bearer is sufficient, other telecommunicationservices benefit from the use of multiple bearers; each tailored to suit the characteristics of the user planeinformation to be transported. This is particularly true for multi-media applications involving audio, videoand data. The call provides
37、 a context in which the various bearers can exist and a means of binding thebearers together.6.2 Relationship to call control architectureBearer control requires functionality, and hence a BC entity, at each terminal and at every network nodethrough which the bearer is routed. This is in contrast to
38、 call control, which involves a CC entity only atthe terminals and selected network nodes. Each bearer can be routed independently of other bearers andindependently of the routing of call control signalling associations. However, each bearer is required to berouted through each network node at which
39、 there is a CC entity, and hence have a BC entity at each ofthese nodes, so that the CC entity can manage the bearer if required. This is illustrated in Figure 1 and a- 4 -single bearer that has a BC entity collocated with each CC entity and an additional BC entity (e.g. at atransit node) located be
40、tween the second and third CC entities.Figure 1 - Relationship of call control and bearer control architectureNOTESignalling between CC entities is outside the scope of this Standard.6.3 Capabilities supported by this StandardThis Standard builds upon the capabilities in ECMA-266 to enable the separ
41、ate control of bearers beingassociated to a multiconnection call.6.4 General overviewThis Standard presents the procedures, messages and information elements needed for establishing,maintaining and clearing of bearer connections being associated to a point-to-point multiconnection call.After a multi
42、connection call has been initiated or has progressed to the active state, bearer connections canbe added to the call by individual bearer connection setup requests from the calling party or the calledparty, using the separated bearer control protocol specified in this Standard, which are based on th
43、eprocedures of ECMA-266. Each new connection setup request shall use a new call reference (see clause 9of ECMA-266). Bearers may be established or released from the multiconnection call at any time while notmodifying the call state. New connections can be established by the calling party or the call
44、ed party bysending a SETUP message as defined in ECMA-266, which in addition contains the Call associationinformation element in order to associate that bearer to the multiconnection call. The calling party or thecalled party can release connections from the call by sending a RELEASE message as defi
45、ned inECMA-266.The individual bearers are controlled independently. In particular multiple bearer connection establishmentrequests may be initiated in parallel (i.e. the requesting party does not need to wait for a response related toone bearer connection setup request before issuing another one). S
46、imilarly, multiple bearer connectionrelease requests may be pending at the same time (i.e. the requesting party does not need to wait for aresponse related to one release connection request before issuing the next one).Any ATM transfer capability available at the interface may be requested independe
47、ntly for each of thebearers associated to a multiconnection call, using appropriate basic call information elements (see clauses8.5.7 to 8.5.10 of ECMA-266). Furthermore, the ATM traffic parameter negotiation applies independentlyto each bearer at bearer establishment time using the procedures defin
48、ed in clause 9.2 of ECMA-266.7 Operational requirements7.1 Provision and withdrawalThe provision of this capability is within a single private network.BCCCCC BC BC CC BC CC BCCall Segment Call SegmentCall SegmentTerminalEdge Switch Transit Switch Edge SwitchTerminale.g.DSS2/UNIe.g.DSS2/UNIB-QSIG B-Q
49、SIG- 5 -7.2 Requirements on the preceding sideNone beyond the support of the multiconnection call capability related control protocols.7.3 Requirements on the succeeding sideNone beyond the support of the multiconnection call capability related control protocols.8 Primitive definitions and state definitions8.1 Primitive definitionsClause 6.3 of ECMA-266 shall apply. No additional primitives between B-QSIG layer 3 and the SignallingATM Adaptation Layer are defined for the purpose of this Standard.8.2 State definitions8.2.1 B-QSIG connection statesThe bearer connection states that m
