SIST EN 301 347 V6.8.1:2003

• Abstract:

  CRs from CN#8

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.070.50 - Global System for Mobile Communication (GSM)
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Mandate: BC-T-330
• Ref Project: ETSI EN 301 347 V6.8.1 (2000-12) - Digital cellular telecommunications system (Phase 2+) (GSM); General Packet Radio Service (GPRS); GPRS Tunnelling Protocol (GTP) across the Gn and Gp Interface (GSM 09.60 version 6.8.1 Release 1997)

SIST EN 301 347 V6.8.1:2003 is the Slovenian standard adopted from ETSI EN 301 347 Version 6.8.1. It specifies the GPRS Tunnelling Protocol (GTP) across the Gn and Gp interfaces in GSM Phase 2+, defining how SGSNs and GGSNs signal, create tunnels, and carry user packets in the GPRS backbone. Engineers use it to implement and verify GTP message handling, PDP context procedures, and inter-SGSN mobility support.

What does SIST EN 301 347 V6.8.1:2003 specify?

SIST EN 301 347 V6.8.1:2003 specifies the protocol between GSN nodes for the General Packet Radio Service (GPRS), both for signalling and for user data transfer. The scope covers the Gn interface within a PLMN and the Gp interface between different PLMNs.

The document is organized into clauses on scope, references, definitions and abbreviations, general rules, header format, signalling plane, transmission plane, path protocols, error handling, inter-PLMN communication, IP use, and GTP parameters.

Annex	What it covers
Annex A	Naming convention for Routing Area Identities and GPRS Support Nodes
Annex B	A method for sequence number checking
Annex C	Document change history

What are the key requirements of SIST EN 301 347 V6.8.1:2003?

• Clauses 4 to 6 define GTP as the protocol used only by SGSNs and GGSNs, with a fixed 20-octet GTP header. This matters because every implementation must parse the same header fields: Version, MessageType, Length, SequenceNumber, Flow Label, SNDCP N-PDU Number, and TID.

• Clause 7 separates the signalling plane from the transmission plane. Signalling creates, updates, and deletes tunnels, while the transmission plane carries T-PDUs inside G-PDUs. In practice, this is the difference between session control and actual packet forwarding.

• Clauses 7.4 and 7.5 define path management and tunnel management messages such as EchoRequest/EchoResponse, CreatePDPContext, UpdatePDPContext, DeletePDPContext, and the corresponding anonymous access versions. These procedures are what bring a PDP context up, change its parameters, or tear it down.

• Clauses 7.5 and 7.6 use information elements such as QoS Profile, AccessPointName, EndUserAddress, GSNAddress, MSISDN, Recovery, and ChargingID. For the reader, this means the context setup messages carry both service settings and addressing data that the peer node must store and use later.

• Clause 7.7 covers mobility management between SGSNs with IdentificationRequest/Response and SGSNContextRequest/Response/Acknowledge. It transfers MMContext and active PDPContext data so that an MS can move between SGSNs without losing its session state.

• Clause 7.8 defines reliable delivery with per-path queues, unique sequence numbers, the T3-RESPONSE timer, and the N3-REQUESTS retry limit. This is the part that tells an implementation how to retransmit signalling and when to treat a path as failed.

• Clauses 8 to 12 define packet tunnelling, path protocols, error handling, restart counters, and IP behaviour. UDP/IP is the path protocol for signalling and connection-less T-PDUs, TCP/IP is the recommended connection-oriented path, IPv4 is the IP version used in this phase, and GTP over Gp carries no built-in security protection.

What terms does SIST EN 301 347 V6.8.1:2003 define?

• G-PDU - A GTP packet made of a GTP header plus a T-PDU payload.
• T-PDU - The original packet from an MS or an external packet data network node that is tunnelled by GTP.
• GTP tunnel - The association of two PDP contexts in different GSN nodes, identified by a Tunnel ID.
• MMContext - The set of mobility management and security data held in the MS and GSNs for a GPRS subscriber.
• PDPContext - The set of session-management data held in the MS and GSNs for a PDP address.
• TID - The Tunnel ID, made from an MMContextID and an NSAPI.
• NSAPI - The Network Service Access Point Identifier, an integer from 0 to 15 that identifies a PDP context.
• QoS - Quality of Service values negotiated for GPRS backbones and PDP context procedures.

Who uses SIST EN 301 347 V6.8.1:2003?

SIST EN 301 347 V6.8.1:2003 is used by GSM/GPRS core network vendors, SGSN and GGSN implementers, and operators running GPRS backbone networks. It is also used by test labs and integration teams that verify context activation, update, deactivation, roaming behaviour, and error handling on Gn and Gp.

It matters in practice for software implementation, interoperability testing, fault tracing, charging-related data handling, and mobility procedures such as GPRS Attach and Inter-SGSN Routeing Update.

Which standards are used with SIST EN 301 347 V6.8.1:2003?

Reference	Contribution
GSM01.04	Abbreviations and acronyms
GSM03.03	Numbering, addressing and identification
GSM03.07	Restoration procedures
GSM03.20	Security related network functions
GSM03.60	GPRS service description and control procedures
GSM03.64	Overall description of the GPRS radio interface
GSM04.08	Mobile radio interface layer 3 and coding for several IEs
GSM04.64	LLC layer specification for MS-SGSN operation
GSM09.02	MAP specification and MAP cause values
STD0005	Internet Protocol (IP)
STD0006	User Datagram Protocol (UDP)
STD0007	Transmission Control Protocol (TCP)
RFC1700	Assigned numbers for protocol values
RFC2181	DNS specification clarifications
ITU-T X.25	Packet-mode DTE/DCE interface
ITU-T X.121	International numbering plan for public data networks

What does the SIST EN 301 347 V6.8.1:2003 document contain?

The document contains the GTP header layout, bit definitions, and message-type table for signalling and data transfer. It gives detailed message formats for path management, tunnel management, location management, mobility management, and error indication, together with the information elements used in each procedure.

It also includes coding figures for key information elements such as Cause, IMSI, RAI, TLLI, P-TMSI, QoS Profile, ChargingID, EndUserAddress, MMContext, and PDPContext. For implementation work, it provides the message structures and field meanings needed for protocol development, validation, and interoperability testing.

The transmission-plane sections explain G-PDU encapsulation, sequence number handling, and how T-PDUs are carried across GSN pairs. The document also covers UDP/IP and TCP/IP path use, IPv4 fragmentation handling, and protocol error handling, including version mismatch and invalid information element cases.

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Digital cellular telecommunications system (Phase 2+) (GSM); General Packet Radio Service (GPRS); GPRS Tunnelling Protocol (GTP) across the Gn and Gp Interface (GSM 09.60 version 6.8.1 Release 1997)33.070.50Globalni sistem za mobilno telekomunikacijo (GSM)Global System for Mobile Communication (GSM)ICS:Ta slovenski standard je istoveten z:EN 301 347 Version 6.8.1SIST EN 301 347 V6.8.1:2003en01-december-2003SIST EN 301 347 V6.8.1:2003SLOVENSKI
STANDARD
ETSIEN301347V6.8.1(2000-12)EuropeanStandard(Telecommunicationsseries)Digitalcellulartelecommunicationssystem(Phase2+);GeneralPacketRadioService(GPRS);GPRSTunnellingProtocol(GTP)acrosstheGnandGpInterface(GSM09.60version6.8.1Release1997)GLOBALSYSTEMFORMOBILECOMMUNICATIONSRSIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)2(GSM09.60version6.8.1Release1997)ReferenceREN/TSGN-040960Q6R3KeywordsDigitalcellulartelecommunicationssystem,GlobalSystemforMobilecommunications(GSM)ETSI650RoutedesLuciolesF-06921SophiaAntipolisCedex-FRANCETel.:[phone]Fax:[phone]SiretN°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:[e-mail]opartmaybereproducedexceptasauthorizedbywrittenpermission.Thecopyrightandtheforegoingrestrictionextendtoreproductioninallmedia.©EuropeanTelecommunicationsStandardsInstitute2000.Allrightsreserved.SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)3(GSM09.60version6.8.1Release1997)ContentsIntellectualPropertyRights.6Foreword.61Scope.72References.73Definitionsandabbreviations.83.1Definitions.83.2Abbreviations.94General.95Transmissionorderandbitdefinitions.106GTPheader.117SignallingPlane.127.1Signallingprotocol.127.2SignallingMessageFormats.137.3UsageoftheGTPHeader.137.4PathManagementmessages.147.4.1EchoRequest.147.4.2EchoResponse.147.4.3VersionNotSupported.157.5TunnelManagementmessages.157.5.1CreatePDPContextRequest.157.5.2CreatePDPContextResponse.177.5.3UpdatePDPContextRequest.187.5.4UpdatePDPContextResponse.197.5.5DeletePDPContextRequest.207.5.6DeletePDPContextResponse.217.5.7CreateAAPDPContextRequest.217.5.8CreateAAPDPContextResponse.227.5.9DeleteAAPDPContextRequest.247.5.10DeleteAAPDPContextResponse.247.5.11ErrorIndication.247.5.12PDUNotificationRequest.257.5.13PDUNotificationResponse.257.5.14PDUNotificationRejectRequest.267.5.15PDUNotificationRejectResponse.277.6LocationManagementmessages.277.6.1SendRouteingInformationforGPRSRequest.287.6.2SendRouteingInformationforGPRSResponse.287.6.3FailureReportRequest.297.6.4FailureReportResponse.297.6.5NoteMSGPRSPresentRequest.307.6.6NoteMSGPRSPresentResponse.307.7MobilityManagementmessages.307.7.1IdentificationRequest.317.7.2IdentificationResponse.317.7.3SGSNContextRequest.327.7.4SGSNContextResponse.327.7.5SGSNContextAcknowledge.337.8Reliabledeliveryofsignallingmessages.347.9Informationelements.347.9.1Cause.357.9.2InternationalMobileSubscriberIdentity(IMSI).377.9.3RouteingAreaIdentity(RAI).37SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)4(GSM09.60version6.8.1Release1997)7.9.4TemporaryLogicalLinkIdentity(TLLI).387.9.5PacketTMSI(P-TMSI).387.9.6QualityofService(QoS)Profile.387.9.7ReorderingRequired.397.9.8AuthenticationTriplet.397.9.9MAPCause.397.9.10P-TMSISignature.407.9.11MSValidated.407.9.12Recovery.407.9.13Selectionmode.417.9.14FlowLabelDataI.417.9.15FlowLabelSignalling.417.9.16FlowLabelDataII.427.9.17ChargingID.427.9.18EndUserAddress.427.9.19MMContext.447.9.20PDPContext.457.9.21AccessPointName.487.9.22ProtocolConfigurationOptions.487.9.23GSNAddress.487.9.24MSInternationalPSTN/ISDNNumber(MSISDN).497.9.25PrivateExtension.498TransmissionPlane.498.1ProtocolStack.508.1.1UsageoftheGTPHeader.508.1.1.1UsageoftheSequenceNumber.508.2TunnellingbetweenSGSNs.518.3TunnellingbetweenGGSNs.519PathProtocols.519.1UDP/IP.519.1.1UDPHeader.519.1.1.1Signallingrequestmessages.519.1.1.2Signallingresponsemessages.519.1.1.3EncapsulatedT-PDUs.519.1.2IPHeader.519.1.2.1SignallingrequestmessagesandEncapsulatedT-PDUs.519.1.2.2Signallingresponsemessages.529.2TCP/IP.529.2.1TCPHeader.529.2.2IPHeader.5210Errorhandling.5210.1Protocolerrors.5210.1.1DifferentGTPversions.5310.1.2GTPMessagetooshort.5310.1.3UnknownGTPsignallingmessage.5310.1.4UnexpectedGTPsignallingmessage.5310.1.5Missingmandatorilypresentinformationelement.5310.1.6InvalidLength.5310.1.7Invalidmandatoryinformationelement.5310.1.8Invalidoptionalinformationelement.5310.1.9Unknowninformationelement.5410.1.10Outofsequenceinformationelements.5410.1.11Unexpectedinformationelement.5410.1.12Repeatedinformationelements.5410.1.13Incorrectoptionalinformationelements.5410.2Pathfailure.5410.3MSdetach.5410.4RestorationandRecovery.54SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)5(GSM09.60version6.8.1Release1997)11Inter-PLMNGTPcommunicationovertheGpinterface.5512IP,thenetworkingtechnologyusedbyGTP.5512.1IPversion.5512.2IPfragmentation.5512.2.1MOdirection.5512.2.2MTdirection.5512.2.3TunnellingfromoldtonewSGSN.5613GTPparameters.5613.1Timers.5613.2Others.56AnnexA(informative):Namingconvention.61A.1RoutingAreaIdentities.61A.2GPRSSupportNodes.61AnnexB(informative):Amethodforsequencenumberchecking.62AnnexC(informative):Documentchangehistory.63History.64SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)6(GSM09.60version6.8.1Release1997)IntellectualPropertyRightsIPRsessentialorpotentiallyessentialtothepresentdocumentmayhavebeendeclaredtoETSI.TheinformationpertainingtotheseessentialIPRs,ifany,ispubliclyavailableforETSImembersandnon-members,andcanbefoundinETSISR000314:"IntellectualPropertyRights(IPRs);Essential,orpotentiallyEssential,IPRsnotifiedtoETSIinrespectofETSIstandards",whichisavailablefromtheETSISecretariat.LatestupdatesareavailableontheETSIWebserver(http://www.etsi.org/ipr).PursuanttotheETSIIPRPolicy,noinvestigation,includingIPRsearches,hasbeencarriedoutbyETSI.NoguaranteecanbegivenastotheexistenceofotherIPRsnotreferencedinETSISR000314(ortheupdatesontheETSIWebserver)whichare,ormaybe,ormaybecome,essentialtothepresentdocument.ForewordThisEuropeanStandard(Telecommunicationsseries)hasbeenproducedbyETSITechnicalCommitteeSpecialMobileGroup(SMG).ThepresentdocumentdefinestheGnandGpinterfacesfortheGeneralPacketRadioService(GPRS)withinthedigitalcellulartelecommunicationssystem(Phase2+).ThecontentsofthepresentdocumentaresubjecttocontinuingworkwithinSMGandmaychangefollowingformalSMGapproval.ShouldSMGmodifythecontentsofthepresentdocument,itwillthenbere-submittedforOAPbyETSIwithanidentifyingchangeofreleasedateandanincreaseinversionnumberasfollows:Version6.x.ywhere:6indicatesRelease1997ofGSMPhase2+.xtheseconddigitisincrementedforallchangesofsubstance,i.e.technicalenhancements,corrections,updates,etc.ythethirddigitisincrementedwheneditorialonlychangeshavebeenincorporatedinthespecification.NationaltranspositiondatesDateofadoptionofthisEN:1December2000DateoflatestannouncementofthisEN(doa):31March2001DateoflatestpublicationofnewNationalStandardorendorsementofthisEN(dop/e):30September2001DateofwithdrawalofanyconflictingNationalStandard(dow):30September2001SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)7(GSM09.60version6.8.1Release1997)1ScopeThepresentdocumentdefinestheGnandGpinterfacesfortheGeneralPacketRadioService(GPRS).2ReferencesThefollowingdocumentscontainprovisionswhich,throughreferenceinthistext,constituteprovisionsofthepresentdocument.• Referencesareeitherspecific(identifiedbydateofpublication,editionnumber,versionnumber,etc.)ornon-specific.• Foraspecificreference,subsequentrevisionsdonotapply.• Foranon-specificreference,thelatestversionapplies.• Anon-specificreferencetoanETSshallalsobetakentorefertolaterversionspublishedasanENwiththesamenumber.• ForthisRelease1997document,referencestoGSMdocumentsareforRelease1997versions(version6.x.y).[1]GSM01.04:"Digitalcellulartelecommunicationssystem(Phase2+);Abbreviationsandacronyms".[2]GSM03.03:"Digitalcellulartelecommunicationssystem(Phase2+);Numbering,addressingandidentification".[3]GSM03.07:"Digitalcellulartelecommunicationssystem(Phase2+);RestorationProcedures".[4]GSM03.20:"Digitalcellulartelecommunicationssystem(Phase2+);Securityrelatednetworkfunctions".[5]GSM03.60:"Digitalcellulartelecommunicationssystem(Phase2+);GeneralPacketRadioService(GPRS);ServiceDescription;Stage2".[6]GSM03.64:"Digitalcellulartelecommunicationssystem(Phase2+);GeneralPacketRadioService(GPRS);OveralldescriptionoftheGPRSRadioInterface;Stage2".[7]GSM04.08:"Digitalcellulartelecommunicationssystem(Phase2+);Mobileradiointerfacelayer3-specification".[8]GSM04.64:"Digitalcellulartelecommunicationssystem(Phase2+);MobileStation-ServingGPRSSupportNode(MS-SGSN)LogicalLinkControl(LLC)LayerSpecification".[9]GSM09.02:"Digitalcellulartelecommunicationssystem(Phase2+);MobileApplicationPart(MAP)specification".SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)8(GSM09.60version6.8.1Release1997)[10]STD0005:"InternetProtocol",J.Postel.[11]STD0006:"UserDatagramProtocol",J.Postel.[12]STD0007:"TransmissionControlProtocol",J.Postel.[13]RFC1700:"AssignedNumbers",J.ReynoldsandJ.Postel.[14]RFC2181:"ClarificationstotheDNSSpecification",R.ElzandR.Bush.[15]ITU-TRecommendationX.25:"Interfacebetweendataterminalequipment(DTE)anddatacircuit-terminatingequipment(DCE)forterminalsoperatinginthepacketmodeandconnectedtopublicdatanetworksbydedicatedcircuit".[16]ITU-TRecommendationX.121:"InternationalNumberingPlanforPublicDataNetworks".3Definitionsandabbreviations3.1DefinitionsForthepurposesofthepresentdocument,thefollowingtermsanddefinitionsapply:conditional:whenthepresencerequirementfortheinformationelementisconditional,thereceivingprotocollevelcancheckthepresenceorabsenceofanIEbasedonthereceivedinformationG-PDU:T-PDUplusaGTPheader.AG-PDUissentinapathGTP-Flow:GTPflowisdefinedbytheunidirectionalvirtualaggregationofG-PDUsand/orsignallingmessagesrelatedtooneormoreGTPtunnels.AFlowLabelincludedintheGTPheaderidentifiesaGTPflow.ThemeaningoftheFlowLabelistransparentforthetransmitterside,onlythereceivermayevaluatetheFlowLabelGTPtunnel:GTPtunnelisdefinedbytwoassociatedPDPContextsindifferentGSNnodesandisidentifiedwithaTunnelID.AGTPtunnelisnecessarytoforwardpacketsbetweenanexternalpacketdatanetworkandanMSuserMMContext:informationsetsheldinMSandGSNsforaGPRSsubscriberrelatedtomobilitymanagement(MM)(pleaserefertotheMMContextInformationElement)MMContextID:IMSIorequivalentforuseinconjunctionwithAnonymousAccess(pleaserefertosectionGTPHeader)NSAPI:NetworkServiceAccessPointIdentifier.Anintegervalueintherange[0;15],identifyingacertainPDPContext.ItidentifiesaPDPcontextbelongingtoaspecificMMContextIDpath:UDP/IPpathandTCP/IPpathareexamplesofpathsthatmaybeusedtomultiplexGTPtunnelspathprotocol:PathProtocolistheprotocol(s)usedasabearerofGTPbetweenGSNsPDP:PacketDataProtocol(PDP)isanetworkprotocolusedbyanexternalpacketdatanetworkinterfacingtoGPRSPDPContext:informationsetsheldinMSandGSNsforaPDPaddress(pleaserefertothePDPContextInformationElement)qualityofservice:QualityofServicemaybeapplicablefortheGPRSbackboneifthepathmediasupportsit.SeparatepathswithdifferentprioritiesmaybedefinedbetweenaGSNpair.However,thepossibleuseofQoSintheGGSNisoutsidethescopeoftheGTPspecificationsignallingmessage:GTPsignallingmessagesareexchangedbetweenGSNpairsinapath.ThesignallingmessagesareusedtotransferGSNcapabilityinformationbetweenGSNpairsandtocreate,updateanddeleteGTPtunnelsTCP/IPpath:TCP/IPpathisareliableconnection-orientedpathdefinedbytwoend-pointsandanend-pointisdefinedbyanIPaddressandaTCPportnumber.TCP/IPpathsshouldbeusedwhentheT-PDUsarebasedonconnection-orientedprotocols,suchastheX.25packetlayerprotocolSIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)9(GSM09.60version6.8.1Release1997)T-PDU:originalpacket,forexampleanIPdatagram,fromanMSoranetworknodeinanexternalpacketdatanetwork.AT-PDUisthepayloadthatistunnelledintheGTPtunnelTID:TunnelID(TID)consistsofaMMContextIDandaNSAPIUDP/IPpath:UDP/IPpathisaconnection-lesspathdefinedbytwoend-pointsandanend-pointisdefinedbyanIPaddressandaUDPportnumber.AUDP/IPpathcarriesG-PDUsbetweenGSNnodesrelatedtooneormoreGTPtunnels.AUDP/IPpathshouldbeusedwhentheT-PDUsarebasedonconnection-lessprotocols,suchasIP3.2AbbreviationsAbbreviationsusedinthepresentdocumentarelistedinGSM01.04.Forthepurposesofthepresentdocument,thefollowingadditionalabbreviationsapply:BBBackboneBearerDFDon'tFragmentFFSForFurtherStudyGninterfaceInterfacebetweenGPRSSupportNodes(GSNs)withinaPLMNGpinterfaceInterfacebetweenGPRSSupportNodes(GSNs)indifferentPLMNsGTPGPRSTunnelingProtocolIANAInternetAssignedNumberAuthorityICMPInternetControlMessageProtocolIPInternetProtocolIPv4InternetProtocolversion4IPv6InternetProtocolversion6MTUMaximumTransmissionUnitQoSQualityofServiceTCPTransmissionControlProtocolTIDTunnelIDentifierUDPUserDatagramProtocol4GeneralThepresentdocumentdefinestheGPRSTunnellingProtocol(GTP),i.e.theprotocolbetweenGSNnodesintheGPRSbackbonenetwork.ItincludesboththeGTPsignallinganddatatransferprocedures.GTPisdefinedbothfortheGninterface,i.e.theinterfacebetweenGSNswithinaPLMN,andtheGpinterfacebetweenGSNsindifferentPLMNs.TheseinterfacesrelevanttoGTParebetweenthegreyboxesshowninthefigurebelow.SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)10(GSM09.60version6.8.1Release1997)GiGnGcGpSignallingandDataTransferInterfaceSignallingInterfaceTEPDNUmGbTEMTBSSRGrorGcHLROtherPLMNSGSNGGSNSGSNGTP-MAPprotocolconvertingGSNGnUmGbTEMTBSSRSGSNGnFigure1:GPRSLogicalArchitecturewithinterfacenamedenotationsGTPallowsmultiprotocolpacketstobetunnelledthroughtheGPRSBackbonebetweenGPRSSupportNodes(GSNs).Inthesignallingplane,GTPspecifiesatunnelcontrolandmanagementprotocolthatallowstheSGSNtoprovideGPRSnetworkaccessforaMS.Signallingisusedtocreate,modifyanddeletetunnels.Inthetransmissionplane,GTPusesatunnellingmechanismtoprovideaserviceforcarryinguserdatapackets.Thechoiceofpathisdependentonwhethertheuserdatatobetunnelledrequiresareliablelinkornot.TheGTPprotocolisimplementedonlybySGSNsandGGSNs.NoothersystemsneedtobeawareofGTP.GPRSMSsareconnectedtoaSGSNwithoutbeingawareofGTP.Itisassumedthattherewillbeamany-to-manyrelationshipbetweenSGSNsandGGSNs.ASGSNmayprovideservicetomanyGGSNs.AsingleGGSNmayassociatewithmanySGSNstodelivertraffictoalargenumberofgeographicallydiversemobilestations.5TransmissionorderandbitdefinitionsThemessagesinthepresentdocumentshallbetransmittedinnetworkoctetorderstartingwithoctet1.ThemostsignificantbitofanoctetinaGTPmessageisbit8.IfavalueinaGTPmessagespansseveraloctetsandnothingelseisstated,themostsignificantbitisbit8oftheoctetwiththelowestnumber.Whereinformationelementsarerepeatedwithinamessage,theordershallbedeterminedbytheorderofappearanceinthetabledefiningtheinformationelementsinthemessage.SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)11(GSM09.60version6.8.1Release1997)6GTPheaderTheGTPheadershallbeafixedformat20-octetheaderusedforallGTPmessages.-Versionshallbesetto0toindicatethis,thefirstversionofGTP.Forthetreatmentofotherversions,seesection10.1.1,"DifferentGTPversions".-Spare'1':Theseunusedbitsshallbesetto'1'bythesendingsideandshallnotbeevaluatedbythereceivingside.-SNNisaflagindicatingifSNDCPN-PDUNumberisincludedornot.-MessageTypeindicatesthetypeofGTPmessage.-LengthindicatesthelengthinoctetsoftheGTPmessage(G-PDU),excludingtheGTPheader.Bit8ofoctet3isthemostsignificantbitandbit1ofoctet4istheleastsignificantbitofthelengthfield.-SequenceNumberisatransactionidentityforsignallingmessagesandanincreasingsequencenumberfortunnelledT-PDUs.-SNDCPN-PDUNumberisusedattheInterSGSNRouteingAreaUpdateproceduretoco-ordinatethedatatransmissionbetweentheMSandSGSN.-TIDisthetunnelidentifierthatpointsoutMMandPDPcontexts(seeFigure3:TunnelID(TID)format).-TheflowlabelidentifiesunambiguouslyaGTPflow.AllfieldsintheGTPheadershallalwaysbepresentbutthecontentofthefieldsdiffersdependingoniftheheaderisusedforsignallingmessages(seethesub-sectionUsageoftheGTPHeaderinthesectionSignallingPlane)orT-PDUs(seethesub-sectionUsageoftheGTPHeaderinthesectionTransmissionPlane).BitsOctets876543211VersionSpare'1111'SNN2MessageType3-4Length5-6SequenceNumber7-8FlowLabel9SNDCPN-PDUNumber10Spare'11111111'11Spare'11111111'12Spare'11111111'13-20TIDFigure2:OutlineofGTPheaderSIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)12(GSM09.60version6.8.1Release1997)BitsOctets87654321IMSIdigit2IMSIdigit1IMSIdigit4IMSIdigit3IMSIdigit6IMSIdigit5IMSIdigit8IMSIdigit7IMSIdigit10IMSIdigit9IMSIdigit12IMSIdigit11IMSIdigit14IMSIdigit13NSAPIIMSIdigit15TheIMSIisdefinedinGSM03.03(andincludesMCC,MNCandMSIN).IMSIdigitsthatarenotusedshallbecodedas‘1111’orF(HEX).NOTE:ForAnonymousAccess,theMSINpartoftheIMSIshallbereplacedbyanumberassignedbytheparticularPLMN.TheassignednumbershallnotcollidewithanyMSINusedinthePLMNandshallbeuniquewithinthePLMN.Figure3:TunnelID(TID)format7SignallingPlaneThesignallingplaneinthiscaserelatestoGPRSMobilityManagementfunctionslikeforexampleGPRSAttach,GPRSRouteingAreaUpdateandActivationofPDPContexts.ThesignallingbetweenGSNnodesshallbeperformedbytheGPRSTunnellingProtocol(GTP).GSNGn,GpGSNGTPPathProtocolGTPPathProtocolFigure4:SignallingPlane-Protocolstack7.1SignallingprotocolTheGTPsignallingflowshallbelogicallyassociatedwith,butseparatefrom,theGTPtunnels.ForeachGSN-GSNpaironeormorepathsexist.Oneormoretunnelsmayuseeachpath.GTPshallbethemeansbywhichtunnelsareestablished,used,managedandreleased.Apathmaybemaintainedbykeep-aliveechomessages.ThisensuresthataconnectivityfailurebetweenGSNscanbedetectedinatimelymanner.SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)13(GSM09.60version6.8.1Release1997)7.2SignallingMessageFormatsGTPdefinesasetofsignallingmessagesbetweentwoassociatedGSNs.Thesignallingmessagestobeusedaredefinedinthetablebelow.Table1:SignallingmessagesMessageTypevalue(Decimal)SignallingmessageReference0Forfutureuse.Shallnotbesent.Ifreceived,shallbetreatedasanUnknownmessage.1EchoRequest7.4.12EchoResponse7.4.23VersionNotSupported7.4.34-15Forfutureuse.Shallnotbesent.Ifreceived,shallbetreatedasanUnknownmessage.16CreatePDPContextRequest7.5.117CreatePDPContextResponse7.5.218UpdatePDPContextRequest7.5.319UpdatePDPContextResponse7.5.420DeletePDPContextRequest7.5.521DeletePDPContextResponse7.5.622CreateAAPDPContextRequest7.5.723CreateAAPDPContextResponse7.5.824DeleteAAPDPContextRequest7.5.925DeleteAAPDPContextResponse7.5.1026ErrorIndication7.5.1127PDUNotificationRequest7.5.1228PDUNotificationResponse7.5.1329PDUNotificationRejectRequest7.5.1430PDUNotificationRejectResponse7.5.1531Forfutureuse.Shallnotbesent.Ifreceived,shallbetreatedasanUnknownmessage.32SendRouteingInformationforGPRSRequest7.6.133SendRouteingInformationforGPRSResponse7.6.234FailureReportRequest7.6.335FailureReportResponse7.6.436NoteMSGPRSPresentRequest7.6.537NoteMSGPRSPresentResponse7.6.638-47Forfutureuse.Shallnotbesent.Ifreceived,shallbetreatedasanUnknownmessage.48IdentificationRequest7.7.149IdentificationResponse7.7.250SGSNContextRequest7.7.351SGSNContextResponse7.7.452SGSNContextAcknowledge7.7.553-254Forfutureuse.Shallnotbesent.Ifreceived,shallbetreatedasanUnknownmessage.255T-PDU8.1.17.3UsageoftheGTPHeaderForsignallingmessagestheGTPheadershallbeusedasfollows:-SNNshallbesetto0.-MessageTypeshallbesettotheuniquevaluethatisusedforeachtypeofsignallingmessage.-Lengthshallbethelength,inoctets,ofthesignallingmessageexcludingtheGTPheader.-SNDCPN-PDUNumber:thisfieldisnotyetusedinsignallingmessages.Itshallbesetto255bythesenderandshallbeignoredbythereceiver.SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)14(GSM09.60version6.8.1Release1997)-SequenceNumbershallbeamessagenumbervalidforapathoratunnel.WithinagivensetofcontiguousSequenceNumbersfrom0to65535,agivenSequenceNumbershall,ifused,unambiguouslydefineaGTPsignallingrequestmessagesentonthepathortunnel(seesectionReliabledeliveryofsignallingmessages).TheSequenceNumberinasignallingresponsemessageshallbecopiedfromthesignallingrequestmessagethattheGSNisreplyingto.-TID(seeFigure3:TunnelID(TID)format)shallbesetto0inallPathManagementmessages(seesectionPathManagementmessages),LocationManagementmessages(seesectionLocationManagementmessages)andMobilityManagementmessages(seesectionMobilityManagementmessages).IntheTunnelManagementmessages(seesectionTunnelManagementmessages),TIDshallbeusedtopointouttheMMandPDPContextsinthedestinationGSN.-InallPathManagementmessages(seesectionPathManagementmessages)andLocationManagementmessages(seesectionLocationManagementmessages)theFlowLabelisnotusedandshallbesetto0.IncaseofTunnelManagementmessageandMobilityManagementmessagestheFlowLabelissettotherequestedvalueandpointsouttheGTPflowexceptfortheCreatePDPContextRequestmessageaswellasIdentificationRequest/ResponseandSGSNContextRequestmessage(seesectionMobilityManagementmessages).TheGTPheadermaybefollowedbysubsequentinformationelementsdependentonthetypeofsignallingmessage.Onlyoneinformationelementofeachtypeisallowedinasinglesignallingmessage,exceptfortheAuthenticationTriplet,thePDPContextandtheFlowLabelDataIIinformationelementwhereseveraloccurrencesofeachtypeareallowed.BitsOctets876543211-20GTPheader21-nInformationElement(s)Figure5:GTPheaderfollowedbysubsequentInformationElements7.4PathManagementmessagesThePathManagementmessagesmaybesentbetweenanytypeofGSNpair.7.4.1EchoRequestAnEchoRequestmaybesentonapathtoanotherGSNtofindoutifthepeerGSNisalive(seesectionPathFailure).EchoRequestmessagesmaybesentforeachpathinuse.ApathisconsideredtobeinuseifatleastonePDPcontextusesthepathtotheotherGSN.WhenandhowoftenanEchoRequestmessagemaybesentisimplementationspecificbutanEchoRequestshallnotbesentmoreoftenthanevery60secondsoneachpath.AGSNshallbepreparedtoreceiveanEchoRequestatanytimeanditshallreplywithanEchoResponse.AGSNmayoptionallysendEchoRequestmessages.TheoptionalPrivateExtensioncontainsvendororoperatorspecificinformation.Table2:InformationelementsinanEchoRequestInformationelementPresencerequirementReferencePrivateExtensionOptional7.9.257.4.2EchoResponseThemessageshallbesentasaresponseofareceivedEchoRequest.SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)15(GSM09.60version6.8.1Release1997)TheRecoveryinformationelementcontainsthelocalRestartCounter(seesectionRestorationandRecovery)valuefortheGSNthatsendstheEchoResponsemessage.TheGSNthatreceivesanEchoResponsefromapeerGSNshallcomparetheRestartCountervaluereceivedwiththepreviousRestartCountervaluestoredforthatpeerGSN.Ifnopreviousvaluewasstored,theRestartCountervaluereceivedintheEchoResponseshallbestoredforthepeerGSN.IfthevalueofaRestartCounterpreviouslystoredforapeerGSNdiffersfromtheRestartCountervaluereceivedintheEchoResponsefromthatpeerGSN,theGSNthatsenttheEchoResponseshallbeconsideredasrestartedbytheGSNthatreceivedtheEchoResponse.ThenewRestartCountervaluereceivedshallbestoredbythereceivingentity,replacingthevaluepreviouslystoredforthesendingGSN.IfthesendingGSNisaGGSNandthereceivingGSNisaSGSN,theSGSNshallnotifyanaffectedMSnexttimetheMScontactstheSGSN.AnaffectedMSisanMSthathasatleastoneactivatedPDPcontextthatwasusingtherestartedGGSN.TheSGSNshallconsiderallPDPcontextsusingthepathasinactive.TheoptionalPrivateExtensioncontainsvendororoperatorspecificinformation.Table3:InformationelementsinanEchoResponseInformationelementPresencerequirementReferenceRecoveryMandatory7.9.12PrivateExtensionOptional7.9.257.4.3VersionNotSupportedThismessagecontainsonlytheGTPheaderandindicatesthelatestGTPversionthattheGTPentityontheidentifiedUDP/IPaddresscansupport.7.5TunnelManagementmessagesTheTunnelManagementmessagesarethecontrolandmanagementmessages,definedinGSM03.60,usedtocreate,updateanddeletetunnelstobeabletorouteT-PDUsbetweenaMSandanexternalpacketdatanetworkviaSGSNandGGSN.TheGMM/SMmessagesthatmaytriggerthesendingoftheTunnelManagementmessagesaredefinedinGSM04.08.7.5.1CreatePDPContextRequestACreatePDPContextRequestshallbesentfromaSGSNnodetoaGGSNnodeasapartoftheGPRSPDPContextActivationprocedure.TheGGSNIPaddresswheretheSGSNsendstheCreatePDPContextRequestisthefirstIPaddressinthelistofIPaddressesprovidedbytheDNSserver.AftersendingtheCreatePDPContextRequestmessage,theSGSNmarksthePDPcontextas'waitingforresponse'.InthisstatetheSGSNshallacceptG-PDUsfromtheGGSNbutshallnotsendtheseG-PDUstotheMS.AvalidrequestinitiatesthecreationofatunnelbetweenaPDPContextinaSGSNandaPDPContextinaGGSN.Iftheprocedureisnotsuccessfullycompleted,theSGSNrepeatstheCreatePDPContextRequestmessagetothenextGGSNaddressinthelistofIPaddresses,ifthereisone.Ifthelistisexhaustedtheactivationprocedurefails.TheFlowLabelDataIfieldspecifiesadownlinkflowlabelforG-PDUswhichischosenbytheSGSN.TheGGSNshallincludethisflowlabelintheGTPheaderofallsubsequentdownlinkG-PDUswhicharerelatedtotherequestedPDPcontext.TheFlowLabelSignallingfieldspecifiesadownlinkflowlabelforsignallingmessageswhichischosenbytheSGSN.TheGGSNshallincludethisflowlabelintheGTPheaderofallsubsequentdownlinksignallingmessageswhicharerelatedtotherequestedPDPcontext.TheMSISDNoftheMSispassedtotheGGSNinsidetheCreatePDPContextRequest;Thisadditionalinformationcanbeusedwhenasecureaccesstoaremoteapplicationresidingonaserverisneeded.TheGGSNwouldbeinfactabletoprovidetheuseridentity(i.e.theMSISDN)totheremoteapplicationserver,providingitwiththeleveloftrustgrantedtousersthroughsuccessfullyperformingtheGPRSauthenticationprocedures,withouthavingtore-authenticatetheuserattheapplicationlevel.SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)16(GSM09.60version6.8.1Release1997)IftheMSrequestsadynamicPDPaddressandadynamicPDPaddressisallowed,thenthePDPAddressfieldintheEndUserAddressinformationelementshallbeempty.IftheMSrequestsastaticPDPAddressthenthePDPAddressfieldintheEndUserAddressinformationelementshallcontainthestaticPDPAddress.IncasethePDPaddressescarriedintheEndUserAddressandoptionallyintheProtocolConfigurationOptioninformationelementcontaincontradictinginformation,thePDPaddresscarriedintheEndUserAddressinformationelementtakesthehigherprecedence.TheQualityofServiceProfileinformationelementshallbetheQoSvaluestobenegotiatedbetweentheMSandtheSGSNatPDPContextactivation.TheSGSNshallincludeanSGSNAddressforsignallingandanSGSNaddressforusertraffic,whichmaydifferfromthatprovidedbytheunderlyingnetworkservice(e.g.IP).TheGGSNshallstoretheseSGSNAddressesandusethemwhensendingsignallingonthisGTPtunnelorG-PDUstotheSGSNfortheMS.TheSGSNshallincludeaRecoveryinformationelementintotheCreatePDPContextRequestiftheSGSNisincontactwiththeGGSNfortheveryfirsttimeoriftheSGSNhasrestartedrecentlyandthenewRestartCountervaluehasnotyetbeenindicatedtotheGGSN.TheGGSNthatreceivesaRecoveryinformationelementintheCreatePDPContextRequestmessageelementshallhandleitinthesamewayaswhenreceivinganEchoResponsemessage.TheCreatePDPContextRequestmessageshallbeconsideredasavalidactivationrequestforthePDPcontextincludedinthemessage.TheSGSNshallincludeeithertheMSprovidedAPN,asubscribedAPNoranSGSNselectedAPNinthemessage;theAccessPointNamemaybeusedbytheGGSNtodifferentiateaccessestodifferentexternalnetworks.TheSelectionModeinformationelementshallindicatetheoriginoftheAPNinthemessage.TheoptionalProtocolConfigurationOptionsinformationelementisapplicablefortheenduserprotocol'IP'only.TheSGSNshallselectoneGGSNbasedontheuserprovidedorSGSNselectedAPN.TheGGSNmayhavealogicalnamethatisconvertedtoanaddress.Theconversionmaybeperformedwithanyname-to-addressfunction.Theconvertedaddressshallbestoredinthe"GGSNAddressinUse"fieldinthePDPcontextandbeusedduringtheentirelifetimeofthePDPcontext.NOTE:ADNSquerymaybeusedasthename-to-IPaddressmappingoftheGGSN.TheIPaddressreturnedintheDNSresponseisthenstoredinthe"GGSNAddressinUse"fieldinthePDPcontext.TheSGSNmaysendaCreatePDPContextRequestevenifthePDPcontextisalreadyactive.TheGGSNshallcheckifaPDPcontextalreadyexistsfortheTID.TheexistingparametersinthePDPcontextshallthenbereplacedwiththeparametersintheCreatePDPContextRequestmessage.IfadynamicPDPaddresshasalreadybeenallocatedfortheexistingcontext,thisaddressshouldbeusedandcopiedtotheCreatePDPContextResponsemessage.IftheGGSNusestheMNRGflagandtheflagisset,theGGSNshouldtreattheCreatePDPContextRequestasaNoteMSPresentRequestandcleartheMNRGflag.TheoptionalPrivateExtensioncontainsvendororoperatorspecificinformation.Table4:InformationelementsinaCreatePDPContextRequestInformationelementPresencerequirementReferenceQualityofServiceProfileMandatory7.9.6RecoveryOptional7.9.12SelectionmodeMandatory7.9.13FlowLabelDataIMandatory7.9.14FlowLabelSignallingMandatory7.9.15EndUserAddressMandatory7.9.18AccessPointNameMandatory7.9.21ProtocolConfigurationOptionsOptional7.9.22SGSNAddressforsignallingMandatoryGSNAddress7.9.23SGSNAddressforusertrafficMandatoryGSNAddress7.9.23MSISDNMandatory7.9.24PrivateExtensionOptional7.9.25SIST EN 301 347 V6.8.1:2003

ETSIETSIEN301347V6.8.1(2000-12)17(GSM09.60version6.8.1Release1997)7.5.2CreatePDPContextResponseThemessageshallbesentfromaGGSNnodetoaSGSNnodeasaresponseofaCreatePDPContextRequest.WhentheSGSNreceivesaCreatePDPContextResponsewiththeCausevalueindicating'RequestAccepted',theSGSNactivatesthePDPcontextandmaystarttoforwardT-PDUsto/fromtheMSfrom/totheexternaldatanetwork.TheCausevalueindicatesifaPDPcontexthasbeencreatedintheGGSNornot.APDPcontexthasnotbeencreatedintheGGSNiftheCausediffersfrom'Requestaccepted'.PossibleCausevaluesare:-'RequestAccepted';-'Noresourcesavailable';-'Servicenotsupported';-'Userauthenticationfailed';-'Systemfailure';-'MandatoryIEincorrect';-'MandatoryIEmissing';-'OptionalIEincorrect';-'Invalidmessageformat';-'Versionnotsupported'.'Noresourcesavailable'indicatese.g.thatalldynamicPDPaddressesoccupiedornomemoryavailable'Servicenotsupported'indicatese.g.whentheGGSNdoesnotsupportthePDPtype,PDPaddressorAccessPointName.'Userauthenticationfailed'indicatesthattheexternalpacketnetwo
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