SIST EN 300 948 V7.1.1:2003
(Main)Digital cellular telecommunications system (Phase 2+) (GSM); Group Call Control (GCC) protocol (GSM 04.68 version 7.1.1 Release 1998)
- Abstract
Upgrade from Phase 2+ to Release 1998
- Status
- Published
- Publication Date
- 30-Nov-2003
- Current Stage
- 6060 - National Implementation/Publication (Adopted Project)
- Start Date
- 01-Dec-2003
- Due Date
- 01-Dec-2003
- Completion Date
- 01-Dec-2003
SIST EN 300 948 V7.1.1:2003 is the Slovenian adoption of the ETSI European Standard for the GSM Group Call Control (GCC) protocol. It specifies how GCC operates on the radio interface for the Voice Group Call Service (VGCS) in GSM Phase 2+ / Release 1998, including message formats, state handling, timers, and error handling between the Mobile Station (MS) and the network. The document is relevant when you need to implement, test, or assess group-call behavior in GSM equipment.
What does SIST EN 300 948 V7.1.1:2003 specify?
SIST EN 300 948 V7.1.1:2003 specifies the GCC protocol used by VGCS on the radio interface. Support for the protocol is optional in both the MS and the network, so the standard is about how group-call-capable equipment behaves, not about all GSM equipment.
The document is organized into clauses for references, definitions and abbreviations, applicability, main concepts, elementary procedures, error handling, message definitions, and information element coding. Annex A is an informative change request history.
What are the key requirements of SIST EN 300 948 V7.1.1:2003?
SIST EN 300 948 V7.1.1:2003 defines GCC as a Connection Management (CM) sublayer protocol that works with the Mobility Management (MM) and Radio Resource (RR) sublayers. In practice, this means an implementation has to coordinate call control with radio and mobility procedures, not treat group calling as a standalone feature.
- Clause 4 makes GCC support optional in the MS and the network. A product team therefore needs to decide explicitly whether the implementation will include VGCS group calling.
- Clause 5 models the MS and network as peer finite state machines. This matters because behavior is defined by state transitions, not just by message names.
- Clause 6.1.2 defines MS states such as NULL, GROUPCALLINITIATED, GROUPCALLACTIVE, GROUPCALLPRESENT, GROUPCALLCONNECTIONREQUESTED, and TERMINATIONREQUESTED, plus sub-states of GROUPCALLACTIVE. It also defines the parameters ORIG, COMM, D-ATT, and U-ATT, which an implementation must keep consistent with the current state.
- Clause 6.2 covers group-call establishment. The MS can start a call with SETUP or IMMEDIATESETUP, the network can activate a call, and CONNECT completes establishment. For a buyer or integrator, this is the core call setup behavior to verify in interworking tests.
- Clause 6.3 links active-call behavior to the RR mode and the available channel. The MS changes sub-state when the RR connection mode changes, and it uses timer Tnochannel if no channel is available.
- Clause 6.4 defines termination, abort, and release. TERMINATIONREQUEST is used by the originating MS, while TERMINATION and TERMINATIONREJECT come from the network. This is the part to check when validating hang-up and forced-release scenarios.
- Clause 6.5 defines GETSTATUS, STATUS, and SETPARAMETER. These procedures let the network query current call state and parameters, and ask the MS to change parameter values when that fits the current protocol state.
- Clauses 7 to 9 define error handling and message coding. Unknown transaction identifiers, unsupported message types, missing mandatory information elements, and semantically incorrect messages are handled in specific ways, and clause 9 fixes the coding of PD, TI, MessageType, CallReference, Callstate, Cause, Originatorindication, and Stateattributes.
What terms does SIST EN 300 948 V7.1.1:2003 define?
SIST EN 300 948 V7.1.1:2003 defines the terms used to describe group-call behavior and the related GSM entities.
- group call - The same as a voice group call, used for one-to-many speech service.
- group call channel - The combined uplink/downlink allocated per cell for a particular group call.
- calling user - The GCC entity in the MS that initiates, or has initiated, the group call.
- originating mobile station - The MS that initiates, or has initiated, the group call.
- group receivemode - The mode in which the MS uses the group call channel for reception.
- uplink - The direction from the Mobile Station to the network.
- downlink - The direction from the network to the Mobile Station.
- GCC - Group Call Control.
Who uses SIST EN 300 948 V7.1.1:2003?
SIST EN 300 948 V7.1.1:2003 is used by GSM equipment designers, protocol engineers, and test teams working on VGCS group calling. It is also useful for quality managers and buyers who need to confirm whether an MS or network product supports group-call control and how it behaves during setup, active use, and release.
What changed in SIST EN 300 948 V7.1.1:2003 from the previous edition?
SIST EN 300 948 V7.1.1:2003 is presented as the Release 1998 version 7.1.1 publication. Annex A records corrections to the GetStatus and SetStatus procedures, coding of the CallReference IE, an upgrade to Release 1998, a correction of the reject cause in TERMINATIONREJECT, a message name correction, and the version update to 7.1.1 for publication.
Which standards are used with SIST EN 300 948 V7.1.1:2003?
SIST EN 300 948 V7.1.1:2003 depends on several GSM specifications for abbreviations, service definition, numbering, and lower-layer behavior.
- GSM01.04 - Provides abbreviations and acronyms used throughout the document.
- GSM02.68 - Defines VGCS at Stage 1 and provides the service context.
- GSM03.03 - Provides numbering, addressing, and identification, including the group-call reference coding basis.
- GSM03.67 - Provides the eMLPP priority levels used with the CallReference priority field.
- GSM03.68 - Provides VGCS at Stage 2 and the related service behavior.
- GSM04.06 - Provides the MS-BSS data link layer specification.
- GSM04.07 - Provides general layer 3 signaling rules, including message structure and IE handling.
- GSM04.08 - Provides the mobile radio interface layer 3 specification, including MM, RR, and coding rules used here.
What does the SIST EN 300 948 V7.1.1:2003 document contain?
SIST EN 300 948 V7.1.1:2003 contains state diagrams, procedure descriptions, message content tables, and IE coding rules for GCC. It also includes timer specifications, error-handling rules for malformed or unexpected messages, and the coded meanings of call state, cause, and state-attribute fields. Annex A gives the change request history for the standard.
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Frequently Asked Questions
SIST EN 300 948 V7.1.1:2003 is a standard published by the Slovenian Institute for Standardization (SIST). Its full title is "Digital cellular telecommunications system (Phase 2+) (GSM); Group Call Control (GCC) protocol (GSM 04.68 version 7.1.1 Release 1998)". This standard covers: Upgrade from Phase 2+ to Release 1998
Upgrade from Phase 2+ to Release 1998
SIST EN 300 948 V7.1.1:2003 is classified under the following ICS (International Classification for Standards) categories: 33.070.50 - Global System for Mobile Communication (GSM). The ICS classification helps identify the subject area and facilitates finding related standards.
SIST EN 300 948 V7.1.1:2003 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.NUPLOMHQMDDigital cellular telecommunications system (Phase 2+) (GSM); Group Call Control (GCC) protocol (GSM 04.68 version 7.1.1 Release 1998)33.070.50Globalni sistem za mobilno telekomunikacijo (GSM)Global System for Mobile Communication (GSM)ICS:Ta slovenski standard je istoveten z:EN 300 948 Version 7.1.1SIST EN 300 948 V7.1.1:2003en01-december-2003SIST EN 300 948 V7.1.1:2003SLOVENSKI
STANDARD
ETSIEN300948V7.1.1(2000-04)EuropeanStandard(Telecommunicationsseries)Digitalcellulartelecommunicationssystem(Phase2+);GroupCallControl(GCC)protocol(GSM04.68version7.1.1Release1998)GLOBALSYSTEMFORMOBILECOMMUNICATIONSRSIST EN 300 948 V7.1.1:2003
ETSIETSIEN300948V7.1.1(2000-04)2(GSM04.68version7.1.1Release1998)ReferenceREN/SMG-030468Q7R1KeywordsDigitalcellulartelecommunicationssystem,GlobalSystemforMobilecommunications(GSM)ETSI650RoutedesLuciolesF-06921SophiaAntipolisCedex-FRANCETel.:+33492944200Fax:+33493654716SiretN°34862356200017-NAF742CAssociationàbutnonlucratifenregistréeàlaSous-PréfecturedeGrasse(06)N°7803/88ImportantnoticeIndividualcopiesofthepresentdocumentcanbedownloadedfrom:http://www.etsi.orgThepresentdocumentmaybemadeavailableinmorethanoneelectronicversionorinprint.Inanycaseofexistingorperceiveddifferenceincontentsbetweensuchversions,thereferenceversionisthePortableDocumentFormat(PDF).Incaseofdispute,thereferenceshallbetheprintingonETSIprintersofthePDFversionkeptonaspecificnetworkdrivewithinETSISecretariat.Usersofthepresentdocumentshouldbeawarethatthedocumentmaybesubjecttorevisionorchangeofstatus.InformationonthecurrentstatusofthisandotherETSIdocumentsisavailableathttp://www.etsi.org/tb/status/Ifyoufinderrorsinthepresentdocument,sendyourcommentto:editor@etsi.frCopyrightNotificationNopartmaybereproducedexceptasauthorizedbywrittenpermission.Thecopyrightandtheforegoingrestrictionextendtoreproductioninallmedia.©EuropeanTelecommunicationsStandardsInstitute2000.Allrightsreserved.SIST EN 300 948 V7.1.1:2003
ETSI3ETSIEN300948V7.1.1(2000-04)(GSM04.68version7.1.1Release1998)ContentsIntellectualPropertyRights.5Foreword.51Scope.62References.63Definitionsandabbreviations.63.1Definitions.63.2Abbreviations.74Applicability.75Mainconcepts.76ElementaryproceduresforGroupCallControl.86.1Overview.86.1.1General.86.1.2Groupcallcontrolstates.106.1.2.1GroupcallcontrolstatesattheMSsideoftheinterface.106.1.2.1.1AttributesandparametersofGCCintheMS.106.1.2.1.2NULL(U0).106.1.2.1.3MMCONNECTIONPENDING(U0.p).106.1.2.1.4GROUPCALLINITIATED(U1).106.1.2.1.5GROUPCALLACTIVE(U2).116.1.2.1.6GROUPCALLPRESENT(U3).116.1.2.1.7GROUPCALLCONNECTIONREQUESTED(U4).116.1.2.1.8TERMINATIONREQUESTED(U5).116.1.2.1.9Sub-statesoftheGroupcallactivestate.116.1.2.1.10GCCTimersintheMS.126.1.2.1.11Consistencyofparametersandstates.126.1.2.2Groupcallcontrolstatesatthenetworksideoftheinterface.136.1.2.2.1NULL(StateN0).136.1.2.2.2GROUPCALLINITIATED(N1).136.1.2.2.3GROUPCALLACTIVE(N2).136.1.2.2.4GROUPCALLESTABLISHMENTPROCEEDING(N3).136.1.2.2.5TERMINATIONREQUESTED(N4).136.2Proceduresforestablishmentofagroupcall.136.2.1Activationofagroupcallbythenetwork.136.2.2Mobileoriginatedestablishment.136.2.2.1Terminationduringmobileoriginatedestablishment.146.2.2.2Abnormalcases.146.2.3MobileterminatinggroupcallestablishmentintheMS.156.3Proceduresduringtheactivestateofagroupcall.156.3.1Mobilestationproceduresintheactivestate.156.3.1.1Sub-statetransitionsintheMS.156.3.2Networkproceduresintheactivestate.166.4Proceduresforrelease,abortion,andterminationofagroupcall.166.4.1Terminationprocedure.166.4.2Abortandreleaseprocedures.166.5Miscellaneousprocedures.176.5.1Statusprocedures.176.5.1.1Getstatusprocedure.176.5.1.2Setparameterprocedure.177Handlingofunknown,unforeseen,anderroneousprotocoldata.177.1General.177.2Messagetooshort.187.3Unknownorunforeseentransactionidentifier.18SIST EN 300 948 V7.1.1:2003
ETSIETSIEN300948V7.1.1(2000-04)4(GSM04.68version7.1.1Release1998)7.4Unknownorunforeseenmessagetype.187.5Non-semanticalmandatoryinformationelementerrors.187.6Unknownandunforeseeninformationelementsinthenon-imperativemessagepart.197.6.1Informationelementsunknowninthemessage.197.6.2Outofsequenceinformationelements.197.6.3RepeatedInformationelements.197.7Non-imperativemessageparterrors.197.7.1SyntacticallyincorrectoptionalInformationelements.197.8Messageswithsemanticallyincorrectcontents.198Messagefunctionaldefinitionsandcontents.208.1CONNECT.208.2GETSTATUS.218.2.1mobileidentity.218.3IMMEDIATESETUP.218.3.1Mobileidentity.228.4SETPARAMETER.228.5SETUP.228.6STATUS.238.6.1Callstate.238.6.2Stateattributes.238.7TERMINATION.248.8TERMINATIONREJECT.248.9TERMINATIONREQUEST.249Contentsofinformationelementsvalueparts.259.1ProtocolDiscriminator.259.2Transactionidentifier.259.3MessageType.259.4Otherinformationelements.269.4.1CallReference.269.4.2Callstate.269.4.3Cause.279.4.4Originatorindication.289.4.5Notused.299.4.6SpareHalfOctet.299.4.7Stateattributes.29AnnexA(informative):ChangeRequestHistory.30History.31SIST EN 300 948 V7.1.1:2003
ETSI5ETSIEN300948V7.1.1(2000-04)(GSM04.68version7.1.1Release1998)IntellectualPropertyRightsIPRsessentialorpotentiallyessentialtothepresentdocumentmayhavebeendeclaredtoETSI.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)hasbeenproducedbyETSITechnicalCommitteeSpecialMobileGroup(SMG),andisnowsubmittedfortheETSIstandardsOne-stepApprovalProcedure.ThepresentdocumentspecifiestheGroupCallControl(GCC)protocolusedbytheVoiceGroupCallService(VGCS)ontheradiointerfacewithinthedigitalcellulartelecommunicationssystem(Phase2+).ThecontentsofthepresentdocumentissubjecttocontinuingworkwithinTC-SMGandmaychangefollowingformalTC-SMGapproval.ShouldTC-SMGmodifythecontentsofthepresentdocument,itwillberesubmittedforOAPbyETSIwithanidentifyingchangeofreleasedateandanincreaseinversionnumberasfollows:Version7.x.y7IndicatesGSMPhase2+Release1998;xtheseconddigitisincrementedforallchangesofsubstance,i.e.technicalenhancements,corrections,updates,etc.;ythethirddigitisincrementedwheneditorialonlychangeshavebeenincorporatedinthespecification.NationaltranspositiondatesDateofadoptionofthisEN:31March2000DateoflatestannouncementofthisEN(doa):30June2000DateoflatestpublicationofnewNationalStandardorendorsementofthisEN(dop/e):31December2000DateofwithdrawalofanyconflictingNationalStandard(dow):31December2000SIST EN 300 948 V7.1.1:2003
ETSIETSIEN300948V7.1.1(2000-04)6(GSM04.68version7.1.1Release1998)1ScopeThepresentdocumentspecifiestheGroupCallControl(GCC)protocolusedbytheVoiceGroupCallService(VGCS)ontheradiointerface.2ReferencesThefollowingdocumentscontainprovisionswhich,throughreferenceinthistext,constituteprovisionsofthepresentdocument.• Referencesareeitherspecific(identifiedbydateofpublication,editionnumber,versionnumber,etc.)ornon-specific.• Foraspecificreference,subsequentrevisionsdonotapply.• Foranon-specificreference,thelatestversionapplies.• Anon-specificreferencetoanETSshallalsobetakentorefertolaterversionspublishedasanENwiththesamenumber.• ForthisRelease1998document,referencestoGSMdocumentsareforRelease1998versions(version7.x.y).[1]GSM01.04(ETR350):"Digitalcellulartelecommunicationsystem(Phase2+);Abbreviationsandacronyms".[2]GSM02.68(ETS300925):"Digitalcellulartelecommunicationsystem(Phase2+);"VoiceGroupCallService(VGCS)-Stage1".[3]GSM03.03(ETS300927):"Digitalcellulartelecommunicationsystem(Phase2+);Numbering,addressingandidentification".[4]GSM03.67(ETS300932):"Digitalcellulartelecommunicationsystem(Phase2+);"enhancedMulti-LevelPrecedenceandPre-emptionservice(eMLPP)-Stage2".[5]GSM03.68(ETS300933):"Digitalcellulartelecommunicationsystem(Phase2+);VoiceGroupCallService(VGCS)-Stage2".[6]GSM04.06(ETS300938):"Digitalcellulartelecommunicationsystem;MobileStation-BaseStationSystem(MS-BSS)interfaceDataLink(DL)layerspecification".[7]GSM04.07(ETS300939):"Digitalcellulartelecommunicationsystem(Phase2+);Mobileradiointerfacesignallinglayer3Generalaspects".[8]GSM04.08(ETS300940):"Digitalcellulartelecommunicationsystem(Phase2+);Mobileradiointerfacelayer3specification".3Definitionsandabbreviations3.1DefinitionsDefinitionsusedinthepresentdocumentarealsodefinedinGSM02.68.Forthepurposesofthepresentdocument,thefollowingtermsanddefinitionsapply.attachmentoftheuserconnection:SeeGSM04.08,subclause5.2.callinguser:GCCentityintheMobileStation(MS)initiatingorhavinginitiatedagroupcall.SIST EN 300 948 V7.1.1:2003
ETSI7ETSIEN300948V7.1.1(2000-04)(GSM04.68version7.1.1Release1998)clearingthecontextrelatedtothegroupcallestablishment:AllrunningGCCtimersintherelevantGCCentityarestopped,allattributesintherelevantGCCentityaredeleted.downlink:Networktomobilestationdirection.groupcall:Isusedinthesamesenseas"voicegroupcall".groupcallchannel:Combineduplink/downlinktobeallocatedineachcellofthegroupcallareaforaparticulargroupcall.Theuplinkcanbeusedbythepresentlytalkingservicesubscriberonly.AllMSsofthelisteningservicesubscribersinonecellshalllistentothecommondownlink.groupreceivemode:SeeGSM04.08.originatingmobilestation:Mobilestationinitiatingorhavinginitiatedthegroupcall.(Notethat,incertainsituations,aMSassumestobetheoriginatingMSofagroupcallwithoutactuallybeingtheoriginatingMSofthatgroupcall.NotethattheremaybeoneornoneoriginatingMSforagivengroupcall).uplink:Mobilestationtonetworkdirection.3.2AbbreviationsAbbreviationsusedinthepresentdocumentarealsolistedinGSM01.04.Forthepurposesofthepresentdocument,thefollowingabbreviationsapply:GCCGroupCallControl4ApplicabilitySupportofthegroupcallprotocolisoptionalintheMSandinthenetwork.5MainconceptsThepresentdocumentdescribesthegroupcallcontrol(GCC)protocol,whichisoneoftheprotocolsoftheConnectionManagement(CM)sublayer(seeGSM04.07).ThereisingeneralmorethanoneMSengagedinagroupcall.Consequently,thereisingeneralmorethanoneMSwithaGCCentityengagedinthesamegroupcall,andthereisoneGCCentityinthenetworkengagedinthatgroupcall.UnderwhichconditionsaGCCmessageispassedfromlower(sub-)layerstotheGCCentityisdefinedinthespecificationsofthesub-layers.TheMSshallignoreGCCmessagesthatitreceiveswhichweresentinunacknowledgedmodeandwhichexplicitlyspecifyasdestinationamobileidentitywhichisnotamobileidentityoftheMS.HigherlayersandtheMMsub-layerdecidewhentoacceptparallelGCCtransactionsandwhen/whethertoacceptGCCtransactionsinparalleltootherCMtransactions.Thegroupcallmaybeinitiatedbyamobileuserorbyadispatcher.Specificationofaprotocolfordispatchersisoutofthescopeofthepresentdocument.Hence,inthescopeofthepresentdocument,thereare:-oneGCCentityinthenetwork;and-oneormorethanoneGCCentitiesindifferentMSsengagedinagroupcall,andoneorenoneoftheMSsistheoriginatorofthegroupcall(calledtheoriginatingMSinthepresentdocument).Notethat,incertainsituations,aMSassumestobetheoriginatorofagroupcallwithoutbeingtheoriginator.SIST EN 300 948 V7.1.1:2003
ETSIETSIEN300948V7.1.1(2000-04)8(GSM04.68version7.1.1Release1998)TheoriginatoroftheGCCtransactionchoosestheTransactionIdentifier(TI).AMSnotassumingtobetheoriginatorofthetransactionwillchosethetransactionidentifierreceivedfromthenetwork,settingtheTIflagto1+xmod2wherexisthereceivedTIflag.Thepresentdocumentdescribesthegroupcallcontrolprotocolonlywithregardtotwopeerentities,oneinaMS,theotheroneinthenetwork.Thecallcontrolentitiesaredescribedascommunicatingfinitestatemachineswhichexchangemessagesacrosstheradiointerfaceandcommunicateinternallywithotherprotocol(sub)layers.Inparticular,theGCCprotocolusestheMMandRRsublayerspecifiedinGSM04.08.Thisdescriptioninonlynormativeasfarastheconsequentialexternallyobservablebehaviourisconcerned.Forsimplicity,insteadofusingtheterms"GCCentityintheMS"and"GCCentityinthenetwork",thepresentdocumentoftenusestheterms"MS"and"network"ifnoconfusionmayarise.Certainsequencesofactionsofthetwopeerentitiescompose"elementaryprocedures"whichareusedasabasisforthedescriptioninthepresentdocument.Theseelementaryproceduresaredefinedinclause6.ThenetworkshouldapplysupervisoryfunctionstoverifythattheGCCproceduresareprogressingandifnot,takeappropriatemeanstoresolvetheproblems.This,however,isoutofthescopeofthepresentdocument.6ElementaryproceduresforGroupCallControl6.1Overview6.1.1GeneralTheelementaryproceduresmaybegroupedintothefollowingclasses:-groupcallestablishmentprocedures;-groupcallterminationprocedures;-callinformationphaseprocedures;-miscellaneousprocedures.Figure6.1givesanoverviewofthemainstatesandtransitionsontheMSside.SIST EN 300 948 V7.1.1:2003
ETSI9ETSIEN300948V7.1.1(2000-04)(GSM04.68version7.1.1Release1998)MMConnectionpending0.PGCpresent3Null0GCconnectionrequested4Null0GCinitiated1GCactiveTerminationrequested5States1,2,3,4?L:EST-CNF!H:SETUP-IND(g-id,prio)?L:SETUP-IND(g-id,prio)?H:ABORTREQ!L:JOINGCREQ(g-id)?H:JOINGCREQ?H:SETUP-REQ(g-id,prio)!L:EST-REQ(SETUP)?H:TERM.REQ!L:ABORT-REQ!H:TERM.CNF?H:ABORTREQ!L:ABORTREQ?H:IMMSETUPREQ(g-id,prio)!L:EST-REQ(IMMSETUP)or?TimeoutH!TERMCNF?L:DI(TERMINATION)or?L:DI(TERM.REQ)?H:TERM.REQ!L:DR(TERM.REQ)?H:TERM.REQ*!L:DR(TERM.REQ)?Tnochanceexp!L:ABORTREQ?H:ABORTREQ!L:ABORTREQ!H:JOINGCCNF(mode)?L:JOINGCCNF(mode)?L:DI(CONNECT)!H:SETUP-CNF(mode)[MM-est'd](Explicit)!H:TERM-IND?L:DI(TERMINATION)!L:ABORT-REQ**?L:MM-EST_REJ!H:TERM_CONFFigure6.1:Overviewgroupcallcontrolprotocol/MSside*ifMSassumestobetheoriginatorofthegroupcall**ifnotinRRconnectedmodeSIST EN 300 948 V7.1.1:2003
ETSIETSIEN300948V7.1.1(2000-04)10(GSM04.68version7.1.1Release1998)6.1.2Groupcallcontrolstates6.1.2.1GroupcallcontrolstatesattheMSsideoftheinterfaceTheGCCentityoftheMSisdescribedasanextendedfinitestatemachine.Itperformstransitionsbetween(main)states,andinmainstateGROUPCALLACTIVE(U3)itperformstransitionsbetweensub-states.Ithascertainparametersandattributes,e.g.configurationparametersandbehaviourparameters,whichitsetsandchangesbasedoninteractionwithhigherandlower(sub-)layersandonmessageexchangewithitspeerentity.Ifaconfigurationparameterissettoacertainvalue,theMSshallalsoadapttheconfigurationaccordingly.Behaviourparametersdecideon(partof)thebehaviouroftheGCCentity.WhentheGCCentityintheMSreceivesamessage,itshallfirstanalysewhetheritshallignorethemessage,seeclauses5and7.6.1.2.1.1AttributesandparametersofGCCintheMSForthefollowingbehaviourparameters,thedescriptionisinformative.ParameterDescriptionORIGDependingonthecontext,theMSassumestobetheoriginatorofthecall(ORIG=T)ornottobetheoriginatorofthecall(ORIG=F).COMMDependingonthecontext,theMSassumesthatcommunicationwithitspeerentityisenabledinbothdirections(COMM=T)ornot(COMM=F).ForthefollowingconfigurationparameterstheMSshalladaptitsconfigurationaccordingtotheparametervalueandparameterdefinition.ParameterDefinitionD-ATTD-ATT=TmeansthattheMSattachestheuserconnectionforthegroupcallinthedownlink.D-ATT=FmeansthattheMSdoesnotattachtheuserconnectionforthegroupcallinthedownlink.U-ATTU-ATT=TmeansthattheMSattachestheuserconnectionforthegroupcallintheuplink.U-ATT=FmeansthattheMSdoesnotattachtheuserconnectionforthegroupcallintheuplink.6.1.2.1.2NULL(U0)NogroupcallexistsfortheGCCentity.Whenenteringthestate,parametersshallbesettothefollowingvalues,andconfigurationshallbeadaptedtothenewvaluesofconfigurationparameters:ORIG=F,COMM=F,D-ATT=F,U-ATT=F.6.1.2.1.3MMCONNECTIONPENDING(U0.p)TheGCCentityhasrequestedtheexplicitestablishmentofanMMconnection.Whenenteringthestate,parametersshallbesettothefollowingvalues,andconfigurationshallbeadaptedtothenewvaluesofconfigurationparameters:ORIG=T,COMM=F,D-ATT=F,U-ATT=F.6.1.2.1.4GROUPCALLINITIATED(U1)TheGCCentityhasrequestedthepeerentityinthenetworktoestablishagroupcall.Whenenteringthestate,parametersshallbesettothefollowingvalues,andconfigurationshallbeadaptedtothenewvaluesofconfigurationparameters:ORIG=T,COMM=T,D-ATT=F,U-ATT=F.SIST EN 300 948 V7.1.1:2003
ETSI11ETSIEN300948V7.1.1(2000-04)(GSM04.68version7.1.1Release1998)6.1.2.1.5GROUPCALLACTIVE(U2)Thegroupcallisestablishedatleastinonecell;dependingonthesub-state,theMShasattachedtheuserconnectionintheuplinkand/ordownlink.Thefollowingsub-statesexist:-separatelink(U2sl);-waitforreceivemode(U2wr);-receivemode(U2r);-waitforsendandreceivemode(U2ws);-sendandreceivemode(U2sr);-nochannel(U2nc).6.1.2.1.6GROUPCALLPRESENT(U3)TheMShasreceivedanotificationaboutanongoinggroupcall.Higherlayersarerequestedtoacceptorrejectthecall.Whenenteringthestate,parametersshallbesettothefollowingvalues,andconfigurationshallbeadaptedtothenewvaluesofconfigurationparameters:ORIG=F,COMM=F,D-ATT=F,U-ATT=F.6.1.2.1.7GROUPCALLCONNECTIONREQUESTED(U4)TheMShasreceivedanotificationaboutanongoinggroupcall.Higherlayershavedecidedtoacceptthecall.Whenenteringthestate,parametersshallbesettothefollowingvalues,andconfigurationshallbeadaptedtothenewvaluesofconfigurationparameters:ORIG=F,COMM=F,D-ATT=F,U-ATT=F.6.1.2.1.8TERMINATIONREQUESTED(U5)TheMS(whichassumestobetheoriginatorofthegroupcall)hasbeeninstateU1orU2andhassentaTERMINATIONREQUESTmessagetothenetwork.Whenenteringthestate,parametersshallbesettothefollowingvalues,andconfigurationshallbeadaptedtothenewvaluesofconfigurationparameters:ORIG=T,COMM=T,D-ATT=T,U-ATT=T.6.1.2.1.9Sub-statesoftheGroupcallactivestateNOTE:Controloftheuserconnectionattachmentisseenasagroupcallcontrolfunction.Thisisareasonwhythesub-statesaredistinguished.6.1.2.1.9.1separatelink(U2sl)AdedicatedonetooneRRconnectionexistsbetweenMSandnetwork.Whenenteringthesub-state,parametersshallbesettothefollowingvalues,andconfigurationshallbeadaptedtothenewvaluesofconfigurationparameters:COMM=T,D-ATT=T,U-ATT=T.6.1.2.1.9.2waitforreceivemode(U2wr)TheMShasaskedthenetworktoenterreceivemodebutadedicatedone-to-onechannelisstillassigned.Whenenteringthesub-state,parametersshallbesettothefollowingvalues,andconfigurationshallbeadaptedtothenewvaluesofconfigurationparameters:COMM=T,D-ATT=T,U-ATT=F.6.1.2.1.9.3receivemode(U2r)TheMSusesagroupcallchannel.Whenenteringthesub-state,parametersshallbesettothefollowingvalues,andconfigurationshallbeadaptedtothenewvaluesofconfigurationparameters:COMM=F,D-ATT=T,U-ATT=F.SIST EN 300 948 V7.1.1:2003
ETSIETSIEN300948V7.1.1(2000-04)12(GSM04.68version7.1.1Release1998)6.1.2.1.9.4waitforsendandreceivemode(U2ws)TheMS(whichwasinU2rorU2wr)hasaskedfortheuplink.Whenenteringthesub-state,parametersshallbesettothefollowingvalues,andconfigurationshallbeadaptedtothenewvaluesofconfigurationparameters:COMM=F,D-ATT=T,U-ATT=T.6.1.2.1.9.5sendandreceivemode(U2sr)TheMShasbeeninformedbyitspeerentitythattheuplinkisgranted.Whenenteringthesub-state,parametersshallbesettothefollowingvalues,andconfigurationshallbeadaptedtothenewvaluesofconfigurationparameters:D-ATT=T,U-ATT=T.6.1.2.1.9.6nochannel(U2nc)TheGCCentityhasbeeninformedthatnochanneliscurrentlyavailable.TimerTnochannellisrunning.Whenenteringthesub-state,parametersshallbesettothefollowingvalues,andconfigurationshallbeadaptedtothenewvaluesofconfigurationparameters:COMM=F,D-ATT=T,U-ATT=T.6.1.2.1.10GCCTimersintheMSTable6.1specifiesthetimersusedinGCC.Thedenotationofcolumnsisdefinedasfollows:timer::=nameofthetimer;set::=underwhichconditionsthetimerisset(i.e.,started);stopped::=underwhichconditionsthetimerisstopped;runninginstate(s)::=inwhichstate(s)thetimermayberunning;actionatexpiry::=whichactionstheGCCentityshallperformatexpiry;value::=thedurationbetweensettingthetimerandexpiryofthetimer("s"denotes"second(s)""xx-yy"meansthatanyvaluebetweenxxandyyispermitted).Table6.1:SpecificationoftimersusedinGCCtimersetstoppedrunninginstate(s)actionatexpiryvalueTnochannelwhenenteringU2ncwhenleavingU2ncU2ncseesubclause6.3.13sTMM-estwhenenteringU0.pusingtheset-upprocedurewhenenteringU1usingtheimmediateset-upprocedurewhenleavingU0.porU1U0.p,U1seesubclause6.2.15sTtermwhensendingaTERMINATIONREQUESTwhenreceivingaTERMINATIONorTERMINATIONREJECTU5abortgroupcall10sTconnreqwhenenteringstateU4whenleavingstateU4U4abortgroupcall10-30s6.1.2.1.11ConsistencyofparametersandstatesTheMSshallconsiderthefollowingparametervaluesasinconsistentwiththestateorsub-state:ORIG=TisinconsistentwithstatesU3andU4.COMM=TisinconsistentwithstatesU0,U3,U4,andwithsub-statesU2ncandU2rofstateU2.SIST EN 300 948 V7.1.1:2003
ETSI13ETSIEN300948V7.1.1(2000-04)(GSM04.68version7.1.1Release1998)AllothervaluesofparametersORIG,COMM,D-ATT,andU-ATTshallnotbeconsideredbytheMSasinconsistentwithastateorsub-state.6.1.2.2Groupcallcontrolstatesatthenetworksideoftheinterface6.1.2.2.1NULL(StateN0)NogroupcallexistsfortheGCCentity.6.1.2.2.2GROUPCALLINITIATED(N1)TheGCCentityhasreceivedtheindicationthatapeerentityinaMSwantstoestablishagroupcallforacertaingroupidentity.6.1.2.2.3GROUPCALLACTIVE(N2)Thegroupcallisestablishedinatleastonecell;theremaybeaMSwhichhasseizedtheuplinkornot;theremaybetalkingdispatchersornot.6.1.2.2.4GROUPCALLESTABLISHMENTPROCEEDING(N3)TheGCCentitywantstoacceptthegroupcall,hasinitiatedestablishmentofcorrespondinggroupcallchannels,and,ifthereisacallinguser.hassentaCONNECTmessagetothecallinguser(ifthereisacallinguser).6.1.2.2.5TERMINATIONREQUESTED(N4)TheGCCentityhasaskedlowersub-layerstoterminatethegroupcallinallcellsandwaitsforaconfirmationthatthegroupcallhasbeenterminatedinallcells.6.2Proceduresforestablishmentofagroupcall6.2.1ActivationofagroupcallbythenetworkTheGCCentityinthenetworkmayinitiatetheactivationofagroupcallwithacertaingroupcallreferenceandpriorityinalistofcellsbyaskinglowerlayerstoestablishthegroupcallwiththatgroupcallreferenceandpriorityinthosecells.Itthenwaitsuntilitisinformedbylower(sub-)layersthatresourceactivationwassufficientlysuccessful,andentersstateN2,GCA
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