SIST EN 302 092-1 V1.2.2:2005

• Abstract:

  Specification of procedures, operations, messages, call parameters, ca ll states and timers for establishing, maintaining and releasing a cal l in the context of separation of call control and bearer control at i nterface at SB, coincident SB and TB or QB. This WPS is an update of an earlier WPS drafted in March 1996, work is carried out in cooperation with ECMA TC 32 TG 15

• Status: Published
• Publication Date: 31-Dec-2004
• ICS: 33.040.35 - Telephone networks
• ICS: 33.080 - Integrated Services Digital Network (ISDN)
• Technical Committee: SPN - Services and Protocols for Networks
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Jan-2005
• Due Date: 01-Jan-2005
• Completion Date: 01-Jan-2005
• Ref Project: ETSI EN 302 092-1 V1.2.2 (1999-11) - Broadband Integrated Services Digital Network (B-ISDN) and Broadband Private Integrated 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 control environment; Part 1: Protocol specification

SIST EN 302 092-1 V1.2.2:2005 is the Slovenian adoption of ETSI EN 302 092-1 V1.2.2, a European telecommunications standard for call control in Broadband Integrated Services Digital Network (B-ISDN) and Broadband Private Integrated Services Network (B-PISN). It specifies the protocol used between adjacent Call Control (CC) entities to establish, maintain and release calls in a separated call and bearer control environment, with the message flows, parameters, states and timers needed by implementers, operators and test teams.

What does SIST EN 302 092-1 V1.2.2:2005 specify?

SIST EN 302 092-1 V1.2.2:2005 specifies call control signalling at the QB, SB, TB and coincident SB/TB reference points within and between B-PISN and European B-ISDN access. The protocol is defined for adjacent CC entities, supports calls with none, one or multiple bearers, and is aimed at two-party call control with forward compatibility for some multi-party use.

The document is organized as follows: clauses 1-12 cover scope, references, definitions, abbreviations, the basic model, operational requirements, service primitives and parameters, ASN.1 coding requirements, procedures, timer values, transport mechanisms and SDL diagrams.

Annex	What it covers
A	Bearer co-ordination requirements for CC signalling service users
B	CallDescription handling requirements for CC signalling service users
C	Interworking with networks that do not separate CC and BC, and with simultaneous call and bearer establishment
D	Transport mechanisms
E	Information flow diagrams
F	Void
G	Object identifiers defined in the document

The scope also keeps some topics out of the protocol model, including BC signalling, network screening functions, and multi-party extensions beyond the two-party compatibility described in the text.

What are the key requirements of SIST EN 302 092-1 V1.2.2:2005?

Call setup and release

SIST EN 302 092-1 V1.2.2:2005 defines five service primitives for call control: ESTABLISH-CALL, COMPLETE-CALL, STATUS-CALL, RELEASE-CALL and PROCEED-CALL, plus ERROR. In practice, this gives implementers the request/indication/confirm flow they must map to signalling and to local call handling.

The call establishment sequence depends on the AwaitCompleteIndicator. If it is TRUE, the call can wait for a later COMPLETE-CALL before becoming active; if it is FALSE, the call can become active after the establish exchange completes. This matters because it tells the system when bearer setup may begin.

For release, the protocol uses ReleaseCause values such as normal call clearing, callDescriptionNotAccepted and temporaryFailure. The cause and location travel with the release, so a node can report where the problem occurred.

Information model and change reporting

SIST EN 302 092-1 V1.2.2:2005 carries a CallDescription that contains network-relevant and end-to-end relevant object descriptions. The call object, party end points, associations, service components and OpenCall permissions are all part of that model, so the call state and call permissions can be exchanged explicitly.

STATUS-CALL reports changes to the information model, mainly changes to service components, party status and the OpenCall attribute. In practice, this is the protocol’s way to announce call-related changes after setup without renegotiating the whole call.

Coding, timers and bearer co-ordination

The protocol uses ASN.1 and BER, and its APDUs are invoke, returnResult, returnError and reject. Unrecognized parameters are handled by the ParameterActionIndicator, so implementations can either reject, discard or pass parameters onward in a controlled way.

Timer handling is central: T703, T708, T710 and T701 drive setup, acceptance and clearing behavior. Annex A adds bearer co-ordination rules, including the rule that bearer establishment starts only after the required APDU has been sent or received, and that bearers are released immediately when call release crosses a segment.

Annex C adds gateway interworking rules for networks that do not separate CC and BC, or that only support simultaneous call and bearer establishment. That matters for gateway design because the CC entity in the gateway takes the originating or terminating role needed to bridge the two network types.

What terms does SIST EN 302 092-1 V1.2.2:2005 define?

• Call - An association between two or more users that lets them communicate through one or more networks.
• Call segment - The part of a call between two adjacent CC entities.
• CC entity - The entity in a terminal or network that participates in call control.
• BC entity - The entity in a terminal or network that participates in bearer control.
• CC signalling service user - The part of the CC entity that uses the call control signalling service.
• CallSegmentId - A pair of values that together identify a call segment at its two ends.
• OpenCall - A call attribute that carries permissions for adding parties, connections or service components.
• APDU - Application Protocol Data Unit, the message format used for the CC operations.

Who uses SIST EN 302 092-1 V1.2.2:2005?

SIST EN 302 092-1 V1.2.2:2005 is used by telecom equipment vendors, network operators, gateway designers and conformance test teams working with B-ISDN, B-PISN, DSS2, B-QSIG and SS7 environments. It is relevant for call control implementation, bearer coordination, interworking at network boundaries, and protocol testing of setup, progress, release and exceptional cases.

What changed in SIST EN 302 092-1 V1.2.2:2005 from the previous edition?

The document history shows earlier editions V1.1.1 and V1.2.1 before this publication of V1.2.2. The foreword identifies SIST EN 302 092-1 V1.2.2:2005 as part 1 of the multi-part standard.

Which standards are used with SIST EN 302 092-1 V1.2.2:2005?

• ITU-T X.680, X.681, X.682, X.683 - Define ASN.1 notation, information object specification, constraints and parameterization for the protocol data structures.
• ITU-T X.690 - Defines BER, CER and DER encoding rules used for APDU encoding.
• ITU-T X.880 - Provides remote-operations concepts and object classes used by the protocol.
• ITU-T Z.100 - Provides SDL, the notation used for the state diagrams in clause 12.
• ETS 300 796-1 - Supplies the CO-BI transport mechanism for SB and coincident SB/TB reference points.
• ECMA-254 - Supplies the CO-BI and CL-BI transport mechanisms for the QB reference point.
• EN 300 196-1 - Provides addressing data elements such as PartyNumber.
• Part 2, Part 3 and Part 4 of this series - Provide the PICS proforma, TSS & TP, and ATS plus PIXIT proforma.

What does the SIST EN 302 092-1 V1.2.2:2005 document contain?

The document contains the ASN.1 definitions for operations, errors, object classes and object identifiers, together with the state and timer tables needed to implement the protocol. It also includes SDL diagrams for outgoing and incoming CC behaviour, including call setup, completion, release and error handling.

Annex A and Annex B give the rules for bearer co-ordination and CallDescription handling, while Annex C describes interworking at gateways. Annex D maps the protocol to chosen transport mechanisms, Annex E shows example information flows, and Annex G lists the object identifiers exported by the ASN.1 modules.

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Broadband Integrated Services Digital Network (B-ISDN) and Broadband Private Integrated 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 control environment; Part 1: Protocol specification33.080Digitalno omrežje z integriranimi storitvami (ISDN)Integrated Services Digital Network (ISDN)33.040.35Telefonska omrežjaTelephone networksICS:Ta slovenski standard je istoveten z:EN 302 092-1 Version 1.2.2SIST EN 302 092-1 V1.2.2:2005en01-januar-2005SIST EN 302 092-1 V1.2.2:2005SLOVENSKI
STANDARD
ETSIEN302092-1V1.2.2(1999-11)EuropeanStandard(Telecommunicationsseries)BroadbandIntegratedServicesDigitalNetwork(B-ISDN)andBroadbandPrivateIntegratedServicesNetwork(B-PISN);DigitalSubscriberSignallingSystemNo.two(DSS2),BroadbandInter-ExchangeSignalling(B-QSIG),andSignallingSystemNo.7(SS7);Callcontrolinaseparatedcallandbearercontrolenvironment;Part1:ProtocolspecificationSIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)2ReferenceDEN/SPS-05132-1(jdc90ipc.PDF)KeywordsB-ISDN,DSS2,B-QSIG,SS7,ISDN,broadband,QSIG,ISUP,B-ISUP,bearer,protocolETSIPostaladdressF-06921SophiaAntipolisCedex-FRANCEOfficeaddress650RoutedesLucioles-SophiaAntipolisValbonne-FRANCETel.:[phone]Fax:[phone]SiretN°34862356200017-NAF742CAssociationàbutnonlucratifenregistréeàlaSous-PréfecturedeGrasse(06)N°7803/[e-mail]ETSIdeliverablecanbedownloadedfromhttp://www.etsi.orgIfyoufinderrorsinthepresentdocument,sendyourcommentto:[e-mail]Ideliverablemaybemadeavailableinmorethanoneelectronicversionorinprint.Inanycaseofexistingorperceiveddifferenceincontentsbetweensuchversions,thereferenceversionisthePortableDocumentFormat(PDF).Incaseofdispute,thereferenceshouldbetheprintingonETSIprintersofthePDFversionkeptonaspecificnetworkdrivewithinETSISecretariat.CopyrightNotificationNopartmaybereproducedexceptasauthorizedbywrittenpermission.Thecopyrightandtheforegoingrestrictionextendtoreproductioninallmedia.©EuropeanTelecommunicationsStandardsInstitute1999.Allrightsreserved.SIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)3ContentsIntellectualPropertyRights.6Foreword.61Scope.72References.73Definitions.84Abbreviations.95Basicmodel.95.1SeparationofCallControl(CC)andBearercontrol(BC).95.2Point-to-pointandmulti-partyCC.95.3CCarchitecture.105.4RelationshiptoBCarchitecture.105.5Screeningfunction.116Operationalrequirements.126.1Provisionandwithdrawal.126.2Transportmechanism.127Primitivedefinitionsandstatedefinitions.137.1Serviceprimitives.137.1.1Serviceprimitivearchitecture.137.1.2ESTABLISH-CALL.137.1.3COMPLETE-CALL.147.1.4STATUS-CALL.147.1.5RELEASE-CALL.157.1.6PROCEED-CALL.157.1.7ERROR.157.2Parameters.167.2.1CallsegmentID.167.2.2Calldescription.167.2.3Callchangedparameter.167.2.4Awaitcompleteindicator.167.2.5Bearerestablishmentaddress.167.2.6Releasecause.167.2.7Result.177.2.8Diagnostics.177.3CCstates.177.3.1CallIdle.177.3.2CallInitiated.177.3.3OutgoingCallProceeding.177.3.4CallReady.177.3.5CallPresent.177.3.6IncomingCallProceeding.177.3.7AwaitCallCompletion.177.3.8CallActive.177.3.9CallReleaseRequest.177.3.10CallReleaseIndication.188Codingrequirements.188.1AbstractdefinitionoftheCCoperations.188.2DefinitionofCCObjectSuperClass.218.3DefinitionsofCCObjectClassesintheInformationModel.219Procedures.239.1Callestablishmentrequest.239.1.1PrecedingCCentity.23SIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)49.1.2SucceedingCCentity.249.2Callproceeding.249.2.1PrecedingCCentity.249.2.2SucceedingCCentity.249.3Callaccepted.249.3.1PrecedingCCentity.249.3.2SucceedingCCentity.259.4Completionofcallestablishment.259.4.1PrecedingCCentity.259.4.2SucceedingCCentity.259.5Callstatuschangereport.259.5.1General.259.5.2InitiatingCCentity.269.5.3ReceivingCCentity.269.6Callestablishmentfailure.269.6.1PrecedingCCentity.269.6.2SucceedingCCentity.269.7Callclearing.279.7.1ProceduresattheCCentitythatinitiatescallclearing.279.7.2ProceduresattheCCentitythatrespondstoclearing.289.7.3Callclearingcollision.289.8ExceptionalProcedures.289.8.1TimerExpiry.289.8.1.1ProceduresattheprecedingCCentity.289.8.1.2ProceduresatthesucceedingCCentity.289.8.1.3ProceduresattheCCentitythatinitiatescallclearing.289.8.2ReceiptofAPDUswithunknownCallSegmentId.289.8.3ReceiptofAPDUswithduplicatedCallSegmentId.299.8.4ReceiptofAPDUsoutofsequence.299.8.5ReceiptofRejectAPDUs.299.8.5.1ReceiptofarejectAPDUthatiscorrelatedtoacallEstablishinvoke.299.8.5.2ReceiptofarejectAPDUthatiscorrelatedtoacallProceedinginvoke.299.8.5.3ReceiptofarejectAPDUthatiscorrelatedtoacallCompleteinvoke.299.8.5.4ReceiptofarejectAPDUthatiscorrelatedtoacallStatusinvoke.299.8.5.5ReceiptofarejectAPDUthatiscorrelatedtoacallReleaseinvoke.299.8.5.6ReceiptofarejectAPDUthatiscorrelatedtoacallEstablishreturnresult.309.8.5.7ReceiptofarejectAPDUthatiscorrelatedtoacallEstablishreturnerror.309.8.5.8ReceiptofarejectAPDUthatiscorrelatedtoacallReleasereturnresult.309.8.6HandlingofunrecognizedparameterswithinCC-Operations.3010Parametervalues(Timers).3111Transportmechanism.3112SDLDiagrams.3112.1OutgoingCC-ASE.3412.2IncomingCC-ASE.40SIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)5AnnexA(normative):Bearerco-ordinationrequirementsforCCsignallingserviceusers.47A.1RequirementsataCCentitythatestablishesabearertowardsanadjacentCCentity.47A.2RequirementsataCCentitythatreceivesabearerestablishmentfromanadjacentCCentity.48A.3AdditionalrequirementsatatransitCC.49A.4Requirementoncallclearing.49AnnexB(normative):CallDescriptionhandlingrequirementsforCCsignallingserviceusers.50B.1CalldescriptionhandlingataCCsignallingserviceuserwithinanoriginatingCCentity.50B.2CalldescriptionhandlingataCCsignallingserviceuserwithinatransitCCentity.50B.3CalldescriptionhandlingataCCsignallingserviceuserwithinaterminatingCCentity.51B.4Calldescriptionerrors.51B.5End-to-endrelevantobjecthandlingataCCsignallingserviceuserwithinatransitCCentity.52B.6ChangestotheInformationModel.52B.6.1DeletionofaServiceComponentObject.52B.6.2AdditionofaServiceComponentObject.52B.6.3ChangestotheattributesofthePartyObject.52B.6.4ChangestotheOpenCallattributeoftheCallObject.53AnnexC(normative):Interworking.55C.1InterworkingwithnetworksnotsupportingseparationofCCandBC.55C.1.1Outgoingcallestablishment.55C.1.2Incomingbearerestablishment.55C.1.3Additionofbearerstoanexistingcall.55C.2Interworkingwithsimultaneouscallandbearerestablishment.55C.2.1Outgoingcallestablishment.55C.2.2Incomingcallandbearerestablishment.56C.2.3Additionofbearerstoanexistingcall.56AnnexD(normative):Transportmechanisms.57D.1Connectionoriented-Bearerindependent.57D.2Connectionless-Bearerindependent.57AnnexE(informative):Informationflowdiagrams.58E.1CallEstablishmentusingatwomessagesequence.58E.2CallEstablishmentusingathreemessagesequence.59E.3CallRelease.60AnnexF(informative):Void.61AnnexG(informative):Objectidentifiersdefinedinthepresentdocument.62Bibliography.63History.64SIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)6IntellectualPropertyRightsIPRsessentialorpotentiallyessentialtothepresentdocumentmayhavebeendeclaredtoETSI.TheinformationpertainingtotheseessentialIPRs,ifany,ispubliclyavailableforETSImembersandnon-members,andcanbefoundinSR000314:"IntellectualPropertyRights(IPRs);Essential,orpotentiallyEssential,IPRsnotifiedtoETSIinrespectofETSIstandards",whichisavailablefromtheETSISecretariat.LatestupdatesareavailableontheETSIWebserver(http://www.etsi.org/ipr).PursuanttotheETSIIPRPolicy,noinvestigation,includingIPRsearches,hasbeencarriedoutbyETSI.NoguaranteecanbegivenastotheexistenceofotherIPRsnotreferencedinSR000314(ortheupdatesontheETSIWebserver)whichare,ormaybe,ormaybecome,essentialtothepresentdocument.ForewordThisEuropeanStandard(Telecommunicationsseries)hasbeenproducedinjointactivitybyETSITechnicalCommitteeSignallingProtocolsandSwitching(SPS)andECMATC32–TG15.Thepresentdocumentispart1ofamulti-partstandardcoveringtheDigitalSubscriberSignallingSystemNo.2(DSS2),BroadbandInter-ExchangeSignalling(B-QSIG),andSignallingSystemNo.7(SS7)protocolspecificationfortheBroadbandIntegratedServicesDigitalNetwork(B-ISDN)andBroadbandPrivateIntegratedServicesNetwork(B-PISN)CallControl,asdescribedbelow:Part1:"Protocolspecification";Part2:"ProtocolImplementationConformanceStatement(PICS)proformaspecification";Part3:"TestSuiteStructureandTestPurposes(TSS&TP)specification";Part4:"AbstractTestSuite(ATS)andpartialProtocolImplementationeXtraInformationforTesting(PIXIT)proformaspecification".NationaltranspositiondatesDateofadoptionofthisEN:5November1999DateoflatestannouncementofthisEN(doa):29February2000DateoflatestpublicationofnewNationalStandardorendorsementofthisEN(dop/e):31August2000DateofwithdrawalofanyconflictingNationalStandard(dow):31August2000SIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)71 ScopeThepresentdocumentspecifiesasignallingprotocolforthepurposeofcallcontrolattheQB,SB,TB,andco-incidentSB/TBreferencepointswithin,between,andattheaccesstoBroadbandPrivateIntegratedServicesNetworksandwithin,between,andattheaccesstoEuropeanBroadbandIntegratedServicesDigitalNetworks.Theprotocoloperatesbetweentwoadjacentcallcontrolentities.Theprotocolisapplicabletoaterminalornetworknodeinaseparatedcallandbearer(connection)controlenvironmentforthesupportofcallshavingnone,asinglebearerormultiplebearers.Theprotocolisapplicabletoatwo-partycall.Theprotocolalsoprovidesforwardcompatibilitytotheextentthatanimplementationcanalsooperatewithinamulti-partycallwithotherimplementationsthatuseadditionalcapabilities,providedtheimplementationisdeployedwhereitdoesnotneedtobeawareofmorethantwoparties.ThepresentdocumentisrelatedtootherStandardsinthisserieswhichwilldescribethearchitectureofaseparatedcallandbearercontrolenvironmentandscenariosinwhichsuchanarchitecturecanbeapplied.Theprotocolspecifiedinthepresentdocumentisindependentofthesupportingtransportservice.Theprotocolspecifiedinthepresentdocumentisindependentoftheprotocolusedforbearerestablishment.2 ReferencesThefollowingdocumentscontainprovisionswhich,throughreferenceinthistext,constituteprovisionsofthepresentdocument.•Referencesareeitherspecific(identifiedbydateofpublication,editionnumber,versionnumber,etc.)ornon-specific.•Foraspecificreference,subsequentrevisionsdonotapply.•Foranon-specificreference,thelatestversionapplies.•Anon-specificreferencetoanETSshallalsobetakentorefertolaterversionspublishedasanENwiththesamenumber.[1] ITU-TRecommendationX.680:"Informationtechnology-AbstractSyntaxNotationOne(ASN.1):Specificationofbasicnotation".[2] ITU-TRecommendationX.681:"InformationTechnology-AbstractSyntaxNotationOne(ASN.1):Informationobjectspecification".[3] ITU-TRecommendationX.682:"Informationtechnology-AbstractSyntaxNotationOne(ASN.1):Constraintspecification".[4] ITU-TRecommendationX.683:"Informationtechnology-AbstractSyntaxNotationOne(ASN.1):ParameterizationofASN.1specifications".[5] ITU-TRecommendationX.690:"Informationtechnology-ASN.1encodingrules:SpecificationofBasicEncodingRules(BER),CanonicalEncodingRues(CER)andDistinguishedEncodingRules(DER)".[6] ITU-TRecommendationX.880:"Informationtechnology-Remoteoperations:concepts,modelandnotation".[7] ITU-TRecommendationZ.100:"CCITTspecificationanddescriptionlanguage(SDL)".[8] ETS300796-1:"BroadbandIntegratedServicesDigitalNetwork(B-ISDN);DigitalSubscriberSignallingSystemNo.two(DSS2)protocol;Genericfunctionalprotocol;Coreaspects;Part1:Protocolspecification[ITU-TRecommendationQ.2932.1(1996),modified]".[9] ECMA-254:"BroadbandPrivateIntegratedServicesNetwork(B-PISN)-Inter-ExchangeSignallingProtocol-GenericFunctionalProtocol(B-QSIG-GF)".SIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)8[10]EN300196-1:"IntegratedServicesDigitalNetwork(ISDN);Genericfunctionalprotocolforthesupportofsupplementaryservices;DigitalSubscriberSignallingSystemNo.one(DSS1)protocol;Part1:Protocolspecification".3DefinitionsForthepurposesofthepresentdocumentthefollowingdefinitionsapply:call:associationbetweentwoormoreusersusingatelecommunicationservicetocommunicatethroughoneormorenetworkscallsegment:partofacalllocatedbetweentwoadjacentcallcontrolentitiescallcontrol:functionalityandsignallinginandbetweennetworksandterminalstoeffectthecontrolofacall,excludingthecontrolofindividualbearerscallcontrolentity(CCentity):entitythatislocatedinaterminaloranetworkandthatparticipatesincallcontrolbearercontrol:functionalityandsignallinginandbetweennetworksandterminalstoeffectthecontrolofabearer,thatbearerbeingpartofacallbearercontrolentity(BCentity):entitythatislocatedinaterminaloranetworkandthatparticipatesinbearercontrolbearer:connectionforthetransportofuserplaneinformationbetweenusersinvolvedinacalladjacentcallcontrolentities(adjacentCCentities):withinthecontextofasinglecall,twoCCentitiesthatsignaldirectlytoeachotherwithnointerveningCCentityprecedingCCentity:CCentitythatinitiatescallestablishmentacrossagivencallsegmentsucceedingCCentity:CCentityattheoppositeendofacallsegmentfromtheprecedingCCentityoriginatingCCentity:CCentitythatinitiatescallestablishmentandislocatedinaterminalorequipmentthatfunctionslikeaterminal(e.g.aserverinthenetwork)terminatingCCentity:CCentitytowhichcallestablishmentisdirectedandthatislocatedinaterminalorequipmentthatfunctionslikeaterminaltransitCCentity:CCentitythroughwhichacallpasses,excludingtheoriginatingandterminatingCCentitycallcontrolsignallingserviceprovider:entitywhichprovidesthesignallingservicesofcallcontrolcallcontrolsignallingserviceuser:entitywithintheCCentitytowhichthesignallingservicesofcallcontrolareprovidedNOTE:ThecallcontrolsignallingserviceuserperformstheCallDescriptionhandling,providestheinteractionswithbearercontrol,andinanetworknode,co-ordinatestheincomingandoutgoingsideoftheCCentity(figure6).informationmodel:representationoftheserviceandabstractcommunicationsconfigurationusinganobjectorientedtechniqueparty:addressablesignallingendpointcallingparty:partywhichinitiatesthecallestablishmentcalledparty:anypartyinacallotherthanthecallingpartySIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)94AbbreviationsForthepurposesofthepresentdocument,thefollowingabbreviationsapply:APDUApplicationProtocolDataUnitASN.1AbstractSyntaxNotationOneB-PISNBroadbandPrivateIntegratedServicesNetworkBCBearerControlCCCallControlMMandatoryOOptional5Basicmodel5.1SeparationofCallControl(CC)andBearercontrol(BC)Theprotocolspecifiedinthepresentdocumentisapplicabletoanenvironmentinwhichthecontrolofacallisseparatefromthecontrolofthebearerorbearersthatexistwithinthecontextofthatcall.Inorderfortwouserstocommunicateusingatelecommunicationservice,anassociation,orcall,isestablishedbetweenthetwousers.Withinthecontextofthecall,oneormorebearerscanbeestablishedfortransportinguserplaneinformationbetweentheusers.However,bearersarenotnormallyestablisheduntilthecallhasbeenacceptedbythecalledterminal,andthereforeresourcesrequiredbybearersarenotoccupiedunnecessarilyifthecallcannotbeestablished,e.g.,ifthecalledterminalisunabletoacceptthecallbecauseresourcesarenotavailable.Duringthelife-timeofthecall,bearerscanbeaddedorcleareddownasrequired.Thecallisterminatedbyoneofthetwouserswhenthereisnofurtherneedforcommunication.Terminationofthecallimpliesthatallbearers(ifany)arecleareddown.Althoughforsometelecommunicationservicesasinglebearerissufficient,othertelecommunicationservicesbenefitfromtheuseofmultiplebearers,eachtailoredtosuitthecharacteristicsoftheuserplaneinformationtobetransported.Thisisparticularlytrueformulti-mediaapplicationsinvolvingaudio,videoanddata.Thecallprovidesacontextinwhichthevariousbearerscanexistandameansofbindingthebearerstogether.5.2Point-to-pointandmulti-partyCCInapoint-to-pointconfigurationtheprotocolspecifiedinthepresentdocumentoperatesbetweenanytwoadjacentCCentitiesbetweenthecallingpartyandthecalledparty.Inamulti-partyconfigurationtheprotocolspecifiedinthepresentdocumentoperatesbetweenanytwoadjacentCCentitiesonthepoint-to-pointlegbetweenaco-ordinationpointinthenetworkandacalledparty.Inthiscaseanetworknodeinthecallingparty'snetworktakesresponsibilityforco-ordinatingtheresponsesfrommultiplepoint-to-pointsignallingassociationstothecalledpartiesintoonesignallingassociationtothecallingparty.EnhancementstobemadetotheCCprotocolinordertomakeitsuitablealsoforthissignallingassociationtothecallingpartyincaseofamulti-partycallareoutsidethescopeofthepresentdocument.Figure1showsanexampleconfigurationforamulti-partycallwithtwocalledpartiesinvolved.SIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)10CallingpartyCalledpartyCalledpartyCalledparty'snetworkCalledparty'snetworkCallingparty'snetworkCoordinationpointCallFigure1:Multi-partycallwithtwocalledparties5.3CCarchitectureCCprovidesthemeansofestablishing,maintainingandclearingdownacall,includingtheoperationofanysupplementaryservicesthatrelatetothecallratherthantoindividualbearers.Controlofacalliseffectedbymeansofanumberofcallcontrolentities(CCentities)locatedintheusers'terminalsandinvariousnetworknodes.WhereasBCinvolvesabearercontrolentity(BCentity)ateachnetworknodethroughwhichabearerpasses,CCrequiresaCCentityonlyatthosenetworknodesthatprovidecall-relatedfunctionality,e.g.,thenodesservingtheterminalsconcernedornodesthat,inthecontextofthecall,provideinterworkingbetweennetworks.Inparticular,CCentitiesarenotrequiredatnodesthatwouldonlyprovidetransitfunctionality.TheprecisecriteriafordeterminingwhetheranetworknodeneedstoprovideCCfunctionalityforagivencallareoutsidethescopeofthepresentdocument.ThevariousCCentitiesinvolvedinagivencallarelinkedinseriesbysignallingassociations.TheseCCentitiesandsignallingassociationsarecreatedduringcallestablishmentandcleareddownwhenthecalliscleareddown.TheprotocolspecifiedinthepresentdocumentprovidessuchanassociationbetweenadjacentCCentitiesandconveyscall-relatedsignallinginformationbetweenthoseCCentities.ThatpartofacallbetweentwoCCentitiesthatcommunicatedirectlyviaasinglesignallingassociationisknownasacallsegment.Thisisillustratedinfigure2foracallthatinvolvesfourCCentities(e.g.,oneateachterminalandoneateachnodeservingthoseterminals)andconsequentlythreecallsegments.CCCCCCCCCallsegmentCallsegmentCallsegmentFigure2:CCinvolvingfourCCentities(threecallsegments)5.4RelationshiptoBCarchitectureBCrequiresfunctionality,andhenceaBCentity,ateachterminalandateverynetworknodethroughwhichthebearerisrouted.ThisisincontrasttoCC,whichinvolvesaCCentityonlyattheterminalsandselectednetworknodes.EachbearercanberoutedindependentlyofotherbearersandindependentlyoftherouteingofCCsignallingassociations.However,eachbearerisrequiredtoberoutedthrougheachnetworknodeatwhichthereisaCCentity,andhencehaveaBCentityateachofthesenodes,sothattheCCentitycanmanagethebearerifrequired.Thisisillustratedinfigure3forthesamecallasinfigure2andasinglebearerthathasaBCentitycollocatedwitheachCCentityandanadditionalBCentity(e.g.atatransitnode)locatedbetweenthesecondandthirdCCentities.SIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)11CCBCCCBCBCCCBCCCBCCallsegmentCallsegmentCallsegmentTerminalTerminalEdgeSwitchEdgeSwitchTransitSwitchFigure3:RelationshipofCCandBCarchitectureNOTE:SignallingbetweenBCentitiesisoutsidethescopeofthepresentdocument.5.5ScreeningfunctionThemodelforcallandBCfunctionalentities(figure3)showsallCCentitiesexistingatthesamelocationasBCentities.WhileBCcanexistindependentlyofCC,theoppositedoesnotapply.EachCCentityincludesbearerco-ordinationcapabilities.Althoughatnetworkboundaries,CCentitieswillnormallybepresent,networkboundariescanalsobecrossedwithoutprovisionofaCCentityandtheconnectionsassociatedwiththosecallscanberouteddifferentlyfromeachotherandfromthecall,therebycrossingnetworkboundariesatdifferentlocationsorevenbeingroutedthroughdifferentnetworks.Whereacallcrossesanetworkboundary,anumberoffunctionswillneedtobeperformedwithinCCthatdonotrequirethepresenceofaconnection.Theseinclude:a)servicecontrol.Controloftheprovisionofbasicandsupplementaryservices,andsubscriptionarrangements.Identificationofcorrectserviceprofile;b)translationofnumberingplanswherethetwonetworksusedifferentnumberingplans(e.g.publictoprivate).Evenwherethesamenumberingplanisused,theadditionofthecountrycodemaybenecessary;c)provisionofsomesupplementaryservicesthatprovidesecuritycontrolonanetworkbasis,e.g.closedusergroup;d)supportofsupplementaryservicesrelatedtonumbering(e.g.,DDI,MSN)andrestrictionofnumbers(CLIR,COLR).Thefunctionslistedaboveareoutsidethescopeofthepresentdocument.CCTECCCCCCTEPhysicallinkPhysicallinkonpathofcallCallsegmentAllocationofCCtophysicalTEornetworknodeNetwork1Network2ABCDCallinguserCalleduserFigure4:CalloriginatingandterminatingindifferentnetworksSIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)12Figure4showsanexampleofacalloriginatingandterminatingindifferentnetworks.Ifcallinglineidentificationrestriction(CLIR)appliestothecall,thisinformationwillbeknownattheCCatnodeA,whichcanaddapresentationrestrictedindicatortothecallingpartynumberforwardedonacrossthenextcallsegment.Normally,onexitfromonenetworktoanother,acallingpartynumberwithanassociatedpresentationrestrictedindicatorisnotforwarded,butinsteadjustthepresentationrestrictedindicatorisforwarded.TheabsenceofaCCatnodeB(pointofegresstonetwork2)meansthattherewillbenoopportunitytofilteroutthecallingpartynumberuntiltheCCatnodeDisreached.Thisisclearlyinsecure.Possiblealternativesare:1)EnsurethatthereisaCCatnodeB(andsimilarlyatnodeCtohandlethistypeofsituationinthereversedirection).However,CCsarepointsofbearercoordination,andthepresenceofCCsatnodesBandCwouldforceallbearerstogovianodesBandC.Thiswoulddenythepossibilityofusingotherroutesbetweenthetwonetworks.Forsomebearers,theroutevianodesBandCmightnotbethecheapest,ormaybecongested,ormaynotprovidethedesiredqualityofservice.ItisdesirabletominimizethenumberofCCsinordertoprovidemaximumflexibilityforrouteingbearers.2)EnsurethattheCCatnodeAperformsthefiltering.However,thisrequiresnodeAtohaveknowledgethatthecallsegmentleadstoanothernetwork.Thisknowledgemaynotalwaysbeavailable.Tosolvetheproblemwithoutintroducingthedisadvantagesofalternatives1and2,filtering(screening)functionalitymaybeprovidedatnodeB(andnodeC).Afunctionalentity(screeningfunction)mayoptionallyappearbetweenCCentities,andislocatedasnecessaryatincomingandoutgoinggatewaysbetweennetworks.Figure5showsanexample.Thescreeningfunctionalentityhasnoimpactontheinformationflows,exceptthatthisfunctionalentitymayimposeitselfasatransitpointonanexistingflow.CCBCBCBCBCBCBCBCBCCCCCScreeningfunctionNetwork1Network2BCScreeningfunctionCCUser1User2Figure5:Screeningfunctionalentitiesatnetworkboundaries6Operationalrequirements6.1ProvisionandwithdrawalTheprovisionofthiscapabilitywithinanetworkisanetworkprovideroption.Theprovisionofthiscapabilitybetweennetworksorbetweenanetworkandauserisbybilateralagreement.6.2TransportmechanismThechoiceoftheunderlyingtransportmechanismwithinanetworkisanetworkprovideroption.Thechoiceofthetransportmechanismbetweennetworksorbetweenanetworkandauserisbybilateralagreement.SIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)137Primitivedefinitionsandstatedefinitions7.1Serviceprimitives7.1.1ServiceprimitivearchitectureThefollowingservicesforcallestablishmentandreleasearedefined:ESTABLISH-CALLconfirmedRELEASE-CALLconfirmedCOMPLETE-CALLunconfirmedSTATUS-CALLunconfirmedPROCEED-CALLunconfirmedERRORindicationFigure6showsthearchitecturewhichisassumedfortwoconcatenatedcallsegments.CCsignallingserviceuserCCsignallingserviceproviderCCsignallingserviceproviderCCCCCCCCsignallingserviceuserCCsignallingserviceuserFigure6:Architecture7.1.2ESTABLISH-CALLThisserviceisusedbytheCCsignallingserviceusertoestablishacallanditsinformationmodel.Itisaconfirmedservice.Table1showstheparametersoftheESTABLISH-CALLprimitive.CCsignallingserviceuserCCsignallingserviceproviderCCsignallingserviceuserESTABLISH-CALLresponseESTABLISH-CALLindicationESTABLISH-CALLrequestESTABLISH-CALLconfirmFigure7:ESTABLISH-CALLserviceSIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)14Table1:ESTABLISH-CALLparametersParameternamerequestindicationresponseconfirmationCallsegmentIDMMMMBearerestablishmentaddressMMOOAwaitcompleteindicatorMM--CalldescriptionMMO(seenote)O(seenote)Result--MMDiagnostics--MMNOTE:MandatoryifResultispositive,elseoptional7.1.3COMPLETE-CALLThisserviceisusedbytheCCsignallingserviceusertocompleteestablishmentofacallanditsinformationmodel.Itisanunconfirmedservice.Table2showstheparametersoftheCOMPLETE-CALLprimitive.CCsignallingserviceuserCCsignallingserviceproviderCCsignallingserviceuserCOMPLETE-CALLindicationCOMPLETE-CALLrequestFigure8:COMPLETE-CALLserviceTable2:COMPLETE-CALLparametersParameternamerequestindicationCallsegmentIDMM7.1.4STATUS-CALLThisserviceisusedbytheCCsignallingserviceusertoreportachangetotheinformationmodel.Itisanunconfirmedservice.Table3showstheparametersoftheSTATUS-CALLprimitive.CCsignallingserviceuserCCsignallingserviceproviderCCsignallingserviceuserSTATUS-CALLindicationSTATUS-CALLrequestFigure9:STATUS-CALLserviceTable3:STATUS-CALLparametersParameternamerequestindicationCallsegmentIDMMCallchangedparameterMMSIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)157.1.5RELEASE-CALLThisserviceisusedbytheCCsignallingserviceusertoreleaseacallanditsinformationmodel.Itisaconfirmedservice.Table4showstheparametersoftheRELEASE-CALLprimitive.RELEASE-CALLresponseRELEASE-CALLindicationRELEASE-CALLrequestRELEASE-CALLconfirmCCsignallingserviceuserCCsignallingserviceproviderCCsignallingserviceuserFigure10:RELEASE-CALLserviceTable4:RELEASE-CALLparametersParameternamerequestindicationresponseconfirmationCallsegmentIDMMMMReleasecauseMM--7.1.6PROCEED-CALLThisserviceisusedbytheCCsignallingserviceusertoindicatereceiptofacallatthesucceedingsideofacallsegment.Itisanunconfirmedservice.Table5showstheparametersofthePROCEED-CALLprimitive.CCsignallingserviceuserCCsignallingserviceproviderCCsignallingserviceuserPROCEED-CALLindicationPROCEED-CALLrequestFigure11:PROCEED-CALLserviceTable5:PROCEED-CALLparametersParameternamerequestindicationCallsegmentIDMMBearerestablishmentaddressMM7.1.7ERRORThisindicationprimitiveisusedbytheCCsignallingserviceprovidertoindicatetheoccurrenceofanexceptionalconditiontotheCCsignallingserviceuser.Table6showstheparametersoftheERRORindicationprimitive.SIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)16Table6:ERRORparametersParameternameindicationCallsegmentIDMDiagnosticsM7.2Parameters7.2.1CallsegmentIDApairofvalueswhichtogetheruniquelyidentifiythecallatthetwoadjacentCCentitiesboundingacallsegment.7.2.2CalldescriptionThetypeCallDescription,asusedintheoperationcallEstablish,containsaninformationmodelwhichdescribesthepropertiesofacall.Theinformationmodelcomprisessequencesofnetworkrelevantandend-to-endrelevantobjectdescriptions.Anobjectdescriptionconsistsof:anobjectreference,usedtorefertoparticularinstancesofobjects,whichshouldthereforebeuniquewithinaparticularcalldescription;anobjectstatus,whichisusedforexampletoindicatewhethertheobjectisOptional(O)orMandatory(M);anidentifierthatidentifiestheclassofobjecttowhichtheinstancebelongs;andanargumentoftypespecifictotheclassofobjecttowhichtheinstancebelongs.ACCobjectclassisaclassofobjectthatinheritsthepropertiesofthesuperclassCALLCONTROLOBJECT.EachobjectclassinthissuperclasscomprisesanidentifierandanOargument.Thetypeoftheargumentdependsontheparticularobjectclassinthesuperclass,asidentifiedbytheidentifier.Theargumentdefinesthetypeofattributesofanobjectofthisclass.TheOpenCallparameterindicatestothenon-callownersinacommunicationsconfigurationtheirrightstomodifytheconfiguration.TheOpenCallparameterisanattributeofthecallthatissetbytheuser(CCsignallingserviceuser);itisstoredintheinformationmodelandistransferredinthecalldescription.TheCCprotocolprovidestheproceduresforexchanginginformationinanorderlymanner.ThecallstatuschangereportprovidesthemechanismforinformingallCCsignallingserviceusersinvolvedinthecallofoneormorechangesinthecallpermissions.7.2.3CallchangedparameterThetypeCallChangedParameter,asusedintheoperationcallStatus,containsalistofthoseobjectsoftheinformationmodelwhichhavebeenmodifiedandthemodificationofwhichhastobereportedtotheotherCCsignallingserviceusersinvolvedinthecall.7.2.4AwaitcompleteindicatorHasthevalueTRUEifcallandinformationmodelestablishmentusesathreemessagesequenceorFALSEifcallandinformationmodelestablishmentusesantwomessagesequence.7.2.5BearerestablishmentaddressTheaddressofanetworknode/terminaltowhichbearer(connection)establishmentshallberouted.7.2.6ReleasecauseReasonforacallreleaserequest.SIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)177.2.7ResultPositive/negativeresultforanESTABLISH-CALLrequestorindication.7.2.8DiagnosticsFurtherexplanationoftheresult(e.g.errorvalues)inanESTABLISH-CALLresponse/confirmortheexplanationoftheexceptionalconditionthatcausedanERRORindication.7.3CCstatesThissubclausedescribesthestateswhichexistforaCCsignallingserviceproviderwithinaCCentity.7.3.1CallIdleNocallexists.7.3.2CallInitiatedThisstateexistsataprecedingCCentitywhenarequestforcallestablishmenthasbeensenttothesucceedingCCentitybutnoresponsehasbeenreceived.7.3.3OutgoingCallProceedingThisstateexistsataprecedingCCentitywhenacknowledgementthatthecallisacceptedforthiscallsegmenthasbeenreceivedfromthesucceedingCCentity.7.3.4CallReadyThisstateexistsataprecedingCCentitywhenanindicationhasbeenreceivedfromthesucceedingCCentitythatitisreadytocompletetheestablishmentofthecallanditsinformationmodel.7.3.5CallPresentThisstateexistsatasucceedingCCentitythathasnotyetrespondedtotherequestforcallestablishment.7.3.6IncomingCallProceedingThisstateexistsatasucceedingCCentitythathassenttotheprecedingCCentityacknowledgementthatthecallisacceptedforthiscallsegment.7.3.7AwaitCallCompletionThisstateexistsatasucceedingCCentitythatisawaitinganindicationfromtheprecedingCCentitythatestablishmentofthecallanditsinformationmodelistobecompleted.7.3.8CallActiveThisstateexistsataprecedingCCentitythathasreceivedanindicationthatthecalleduserhasansweredfromthesucceedingCCentity.ThisstateexistsatasucceedingCCentitythathassentanindicationthatthecalleduserhasansweredtotheprecedingCCentity.7.3.9CallReleaseRequestThisstateexistswhenaCCentityhassentoutarequestforcallreleasebutaresponsehasnotyetbeenreceived.SIST EN 302 092-1 V1.2.2:2005

ETSIETSIEN302092-1V1.2.2(1999-11)187.3.10CallReleaseIndicationThisstateexistswhenaCCentityhasreceivedacallreleaseindicationbuttheuserhasnotyetanswered.8Codingrequirements8.1AbstractdefinitionoftheCCoperationsTable7showst
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