ETSI TS 123 079 V3.3.0 (2000-01) TechnicalSpecification Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile Telecommunications System (UMTS); Support of Optimal Routeing (SOR); Technical realisation (3G TS 23.079 version 3.3.0 Release 1999) R GLOBALSYSTEM FOR MOBILECOMMUNICATIONS (3GTS23.079version3.3.0Release1999) 1 ETSITS123079V3.3.0(2000-01) Reference DTS/TSGN-0223079U Keywords GSM,UMTS ETSI Postaladdress F-06921SophiaAntipolisCedex-FRANCE Officeaddress 650RoutedesLucioles-SophiaAntipolis Valbonne-FRANCE Tel.:+33492944200 Fax:+33493654716 SiretN°34862356200017-NAF742C Associationàbutnonlucratifenregistréeàla Sous-PréfecturedeGrasse(06)N°7803/88 Internet [email protected] IndividualcopiesofthisETSIdeliverable canbedownloadedfrom http://www.etsi.org Ifyoufinderrorsinthepresentdocument,sendyour commentto:[email protected] Importantnotice ThisETSIdeliverablemaybemadeavailableinmorethanoneelectronicversionorinprint.Inanycaseofexistingor perceiveddifferenceincontentsbetweensuchversions,thereferenceversionisthePortableDocumentFormat(PDF). Incaseofdispute,thereferenceshallbetheprintingonETSIprintersofthePDFversionkeptonaspecificnetwork drivewithinETSISecretariat. CopyrightNotification Nopartmaybereproducedexceptasauthorizedbywrittenpermission. Thecopyrightandtheforegoingrestrictionextendtoreproductioninallmedia. ©EuropeanTelecommunicationsStandardsInstitute2000. Allrightsreserved. ETSI (3GTS23.079version3.3.0Release1999) 2 ETSITS123079V3.3.0(2000-01) Intellectual Property Rights IPRsessentialorpotentiallyessentialtothepresentdocumentmayhavebeendeclaredtoETSI.Theinformation pertainingtotheseessentialIPRs,ifany,ispubliclyavailableforETSImembersandnon-members,andcanbefound inSR000314:"IntellectualPropertyRights(IPRs);Essential,orpotentiallyEssential,IPRsnotifiedtoETSIinrespect ofETSIstandards",whichisavailablefromtheETSISecretariat.LatestupdatesareavailableontheETSIWebserver (http://www.etsi.org/ipr). PursuanttotheETSIIPRPolicy,noinvestigation,includingIPRsearches,hasbeencarriedoutbyETSI.Noguarantee canbegivenastotheexistenceofotherIPRsnotreferencedinSR000314(ortheupdatesontheETSIWebserver) whichare,ormaybe,ormaybecome,essentialtothepresentdocument. Foreword ThisTechnicalSpecification(TS)hasbeenproducedbytheETSI3rdGenerationPartnershipProject(3GPP). Thepresentdocumentmayrefertotechnicalspecificationsorreportsusingtheir3GPPidentitiesorGSMidentities. TheseshouldbeinterpretedasbeingreferencestothecorrespondingETSIdeliverables.Themappingofdocument identitiesisasfollows: For3GPPdocuments: 3GTS|TRnn.nnn"<title>"(withorwithouttheprefix3G) isequivalentto ETSITS|TR1nnnnn"[Digitalcellulartelecommunicationssystem(Phase2+)(GSM);]UniversalMobile TelecommunicationsSystem;<title> ForGSMdocumentidentitiesoftype"GSMxx.yy",e.g.GSM01.04,thecorrespondingETSIdocumentidentitymaybe foundintheCrossReferenceListonwww.etsi.org/key ETSI 3G TS 23.079 version 3.3.0 Release 99 3 3G TS 23.079 V3.3.0 (1999-12) Contents Foreword............................................................................................................................................................5 1 Scope........................................................................................................................................................6 2 Normative references...............................................................................................................................6 3 Definitions and abbreviations..................................................................................................................7 3.1 Definitions.........................................................................................................................................................7 3.2 Abbreviations.....................................................................................................................................................8 4 Architecture.............................................................................................................................................8 4.1 Optimal routeing for basic mobile-to-mobile calls............................................................................................8 4.2 Optimal routeing for conditional call forwarding............................................................................................10 5 Optimal routeing for basic mobile-to-mobile calls: message flows......................................................11 5.1 Successful outcome..........................................................................................................................................12 5.2 Unsuccessful outcome.....................................................................................................................................12 5.2.1 B subscriber address not recognised as belonging to a GSM PLMN.........................................................12 5.2.2 HLRB or VLRB does not support optimal routeing...................................................................................12 5.2.3 OR charging requirements contravened.....................................................................................................13 6 Optimal routeing for conditional call forwarding: message flows........................................................13 6.1 Early call forwarding.......................................................................................................................................13 6.1.1 Forwarding without interrogation of VLRB...............................................................................................13 6.1.1.1 Successful outcome..............................................................................................................................13 6.1.1.2 Unsuccessful outcome..........................................................................................................................14 6.1.2 Forwarding after interrogation of VLRB...................................................................................................14 6.1.2.1 Successful outcome..............................................................................................................................14 6.1.2.2 Unsuccessful outcome..........................................................................................................................15 6.2 Late call forwarding.........................................................................................................................................16 6.2.1 Successful outcome....................................................................................................................................17 6.2.2 Unsuccessful outcome................................................................................................................................17 6.2.2.1 GMSC does not support OR.................................................................................................................17 6.2.2.2 HLRB does not support OR..................................................................................................................17 6.2.2.3 VMSCB/VLRB does not support OR...................................................................................................17 6.2.2.4 OR charging requirements contravened...............................................................................................17 7 Interactions between optimal routeing and supplementary services......................................................18 7.1 Call forwarding................................................................................................................................................18 7.2 Closed User Group (CUG)..............................................................................................................................18 7.3 Advice of Charge.............................................................................................................................................18 7.4 Call barring......................................................................................................................................................18 7.5 Other supplementary services..........................................................................................................................19 8 Interactions between optimal routeing and other network features.......................................................19 8.1 Operator determined barring............................................................................................................................19 8.2 CAMEL...........................................................................................................................................................19 9 Functional requirements of entities performing optimal routeing.........................................................20 9.1 Charging requirements for optimal routeing....................................................................................................20 9.2 Functional behaviour of VMSCA....................................................................................................................20 9.3 Functional behaviour of VLRA.......................................................................................................................20 9.4 Functional behaviour of GMSC.......................................................................................................................21 9.4.1 Procedure OR_Set_ORA_Parameters........................................................................................................21 9.4.2 Procedure OR_Handle_RCH.....................................................................................................................21 9.4.3 Procedure Route_Permitted........................................................................................................................21 9.4.4 Procedure OR_Handle_SRI_Negative_Response......................................................................................21 9.5 Functional behaviour of HLR..........................................................................................................................28 9.5.1 Procedure OR_HLR_CF............................................................................................................................28 9.5.2 Procedure OR_HLR_Interrogate_VLR......................................................................................................28 ETSI 3G TS 23.079 version 3.3.0 Release 99 4 3G TS 23.079 V3.3.0 (1999-12) 9.6 Functional behaviour of VLRB.......................................................................................................................32 9.6.1 Functional behaviour of VLRB for provision of subscriber information...................................................32 9.6.2 Functional behaviour of VLRB for roaming number allocation................................................................32 9.6.3 Functional behaviour of VLRB when handling an incoming call..............................................................32 9.7 Functional behaviour of VMSCB....................................................................................................................32 9.7.1 Procedure Handle_ORLCF_VMSC...........................................................................................................32 10 Contents of messages.............................................................................................................................34 10.1 Messages on the B interface (MSC-VLR).......................................................................................................34 10.1.1 Send Info For Outgoing Call......................................................................................................................34 10.1.2 Send Info For Outgoing Call negative response.........................................................................................34 10.1.3 Send Info For Incoming Call......................................................................................................................34 10.1.4 Send Info For Incoming Call ack...............................................................................................................34 10.1.5 Send Info For Incoming Call negative response........................................................................................34 10.1.6 Complete Call.............................................................................................................................................35 10.1.7 Process Call Waiting..................................................................................................................................35 10.2 Messages on the C interface (MSC-HLR).......................................................................................................35 10.2.1 Send Routeing Info....................................................................................................................................35 10.2.2 Send Routeing Info ack..............................................................................................................................36 10.2.3 Send Routeing Info negative response.......................................................................................................36 10.3 Messages on the D interface (VLR-HLR).......................................................................................................36 10.3.1 Provide Roaming Number..........................................................................................................................36 10.3.2 Provide Roaming Number ack...................................................................................................................36 10.3.3 Provide Roaming Number negative response............................................................................................37 10.3.4 Provide Subscriber Information.................................................................................................................37 10.3.5 Provide Subscriber Information ack...........................................................................................................37 10.4 Messages on the E interface (MSC-MSC).......................................................................................................37 10.4.1 Resume Call Handling...............................................................................................................................37 10.4.2 Resume Call Handling ack.........................................................................................................................37 10.4.3 Resume Call Handling negative response..................................................................................................38 Annex A (informative): Handling of an IAM at an MSC...................................................................39 Annex B: Change history......................................................................................................................40 History..............................................................................................................................................................41 ETSI 3G TS 23.079 version 3.3.0 Release 99 5 3G TS 23.079 V3.3.0 (1999-12) Foreword This Technical Specification has been produced by the 3GPP. This specification specifies the technical realisation of the first phase of the network feature Support of Optimal Routeing (SOR) within the 3GPP system. The contents of the present document are subject to continuing work within the TSG and may change following formal TSG approval. Should the TSG modify the contents of this TS, it will be re-released by the TSG with an identifying change of release date and an increase in version number as follows: Version 3.y.z where: x the first digit: 1 presented to TSG for information; 2 presented to TSG for approval; 3 Indicates TSG approved document under change control. y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections, updates, etc. z the third digit is incremented when editorial only changes have been incorporated in the specification; ETSI 3G TS 23.079 version 3.3.0 Release 99 6 3G TS 23.079 V3.3.0 (1999-12) 1 Scope This standard specifies the technical realisation of the first phase of the network feature Support of Optimal Routeing (SOR). The first phase of SOR provides: - as a network operator option, a method to route a call from one mobile subscriber directly to another mobile subscriber who is in the same country as the calling mobile subscriber or in the called mobile subscriber's home country, without needing to connect the call via the HPLMN of the called subscriber, even though the called mobile subscriber has roamed outside his HPLMN; - a method to forward calls when a called mobile subscriber who has roamed outside his home country is busy, or is not reachable, or does not reply, to a forwarded-to destination in the HPLMN country of the called subscriber or the VPLMN country of the called subscriber, without needing to connect the forwarded call via the VPLMN of the called subscriber; - a method to combine the optimal routeing described in the first bullet point above with the optimal routeing described in the second bullet point above. OR of a call is permitted only if all entities involved in handling the call support OR. Other cases of optimal routeing (e.g. calls where the calling and called subscribers are in different countries, forwarding to a mobile subscriber or multiple forwarding) will be considered for inclusion in later phases. 2 Normative references The following documents contain provisions which, through reference in this text, constitute provisions of the present document. - References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific. - For a specific reference, subsequent revisions do not apply. - For a non-specific reference, the latest version applies. - A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same number. - For this Release 1999 document, references to 3G documents are for Release 1999 versions (version 3.x.y). [1] 3G TS 21.905: "3G Vocabulary". [2] 3G TS 22.079: "Support of Optimal Routeing (SOR); Service definition (Stage 1)". [3] 3G TS 22.082: "Call Forwarding (CF) Supplementary Services - Stage 1". [4] 3G TS 23.003: "Numbering, addressing and identification". [5] 3G TS 23.018: "Basic call handling; Technical realisation". [6] 3G TS 23.078: "Customized Applications for Mobile network Enhanced Logic (CAMEL) - Phase 3; Stage 2". [7] 3G TS 23.085: "Closed User Group (CUG) Supplementary Services - Stage 2". [8] 3G TS 23.087: "User-to-User (UUS) Supplementary Services - Stage 2". [9] GSM 03.04: "Digital cellular telecommunications system (Phase 2+); Signalling requirements relating to routeing of calls to mobile subscribers". ETSI 3G TS 23.079 version 3.3.0 Release 99 7 3G TS 23.079 V3.3.0 (1999-12) 3 Definitions and abbreviations 3.1 Definitions A subscriber: The calling subscriber, who may be fixed or mobile. B subscriber: The mobile subscriber originally called by the A subscriber. C subscriber: The subscriber to whom the B subscriber has requested that calls be forwarded. The C subscriber may be fixed or mobile. Direct route: A call takes the direct route if the route from the serving PLMN of the A subscriber to the serving PLMN of the B subscriber is defined by the MSRN of the B subscriber rather than by the MSISDN of the B subscriber. Early call forwarding: call forwarding from the IPLMN before the call has been extended to the VPLMN of the forwarding subscriber. HPLMN leg: The portion of the HPLMN route from the serving MSC of the A subscriber to an MSC in the HPLMN of the B subscriber. HPLMN route: A call takes the HPLMN route if the route from the serving MSC of the A subscriber to the serving MSC of the B subscriber is defined by the MSISDN of the called subscriber. This forces the call to be routed via the HPLMN of the B subscriber. Interrogating PLMN (IPLMN): The PLMN which interrogates the HPLMN of the B subscriber to obtain information to route the call to that subscriber or to the forwarded-to destination defined by the called mobile subscriber. The IPLMN is also the VPLMN of the A subscriber. Late call forwarding: call forwarding after the call has been extended to the VPLMN of the forwarding subscriber. Late call forwarding may be invoked in the IPLMN or the VPLMN of the forwarding subscriber. Reference address: The address which defines the maximum charge which the A party is prepared to pay for the call leg which he originates. Routeing address: The address which the GMSC uses to route a call towards the B subscriber or the C subscriber. ETSI 3G TS 23.079 version 3.3.0 Release 99 8 3G TS 23.079 V3.3.0 (1999-12) 3.2 Abbreviations Abbreviations used in this specification are listed in GSM 01.04 [1]. For the purpose of this specification the following abbreviations apply: BOIZC Barring of Outgoing InterZonal Calls BOIZC-exHC Barring of Outgoing InterZonal Calls except those directed to the HPLMN Country CMN CAMEL Modified Number FTN Forwarded-To Number FTNW Forwarded-To NetWork GMSCA The GMSC in the IPLMN, which may also be VMSCA GMSCB The GMSC in HPLMNB GMSCC The GMSC in HPLMNC HLRB The HLR of the B subscriber HLRC The HLR of the C subscriber HPLMNB The HPLMN of the B subscriber HPLMNC The HPLMN of the C subscriber IAM Initial Address Message IPLMN Interrogating PLMN ORLCF Optimal Routeing for Late Call Forwarding PRN Provide Roaming Number PSI Provide Subscriber Information RCH Resume Call Handling SIFIC Send Information For Incoming Call SIFOC Send Information For Outgoing Call SRI(B) Send Routeing Information (Basic call) SRI(F) Send Routeing Information (Forwarding information) VLRA The VLR of the A subscriber VLRB The VLR of the B subscriber VMSCA The VMSC of the A subscriber VMSCB The VMSC of the B subscriber 4 Architecture 4.1 Optimal routeing for basic mobile-to-mobile calls It is a network operator option whether to implement optimal routeing for basic mobile-to-mobile calls. The existing GSM architecture supports the primary technical requirement of optimal routeing for mobile-to-mobile calls (basic OR): that a GMSC can interrogate an HLR in a different PLMN to obtain routeing information for a mobile terminated call (see GSM 03.04 [5]). Three logically distinct PLMNs are involved in the handling of an optimally routed mobile-to-mobile call: - the IPLMN, which is also the VPLMN of the calling mobile subscriber; - the HPLMN of the called mobile subscriber (HPLMNB); - the VPLMN of the called mobile subscriber (VPLMNB). Any two or all three of these PLMNs may be identical; in figure 1 they are shown as distinct. Figure 1 shows the communication between the IPLMN, HPLMNB and VPLMNB for an optimally routed mobile-to- mobile call. ETSI 3G TS 23.079 version 3.3.0 Release 99 9 3G TS 23.079 V3.3.0 (1999-12) IAM IPLMN (ISUP) IAM GMSCA VMSCB (ISUP) VPLMNB VMSCA VLRB Send Routeing Provide Roaming Info/ack Number/ack HLRB HPLMNB Figure 1: Architecture for optimal routeing of basic mobile-to-mobile call In figure 1 and throughout this specification, the term ISUP is used to denote the telephony signalling system used between exchanges. In a given network, any telephony signalling system may be used; the only additional requirement is that GMSCA must be able to signal to VMSCA the destination address which it has used to route the call. If the VMSC of the calling mobile subscriber (VMSCA) is distinct from the GMSC, it constructs an ISUP Initial Address Message (IAM) using the MSISDN of the called subscriber and sends it to the GMSC. If the GMSC, which may be distinct from the VMSC of the calling mobile subscriber but is in the VPLMN of the calling mobile subscriber, is in a different PLMN from HLRB, it requests routeing information from HLRB using the MAP protocol. If HLRB determines that the call can be routed directly from the GMSC to VMSCB without contravening the charging requirements for optimal routeing given in subclause 9.1, it requests a roaming number from VLRB using the MAP protocol, and VLRB returns a roaming number in the Provide Roaming Number ack. HLRB returns the roaming number to the GMSC in the Send Routeing Info ack. The GMSC uses the roaming number to construct an ISUP IAM, which it sends to VMSCB. The call is then handled according to the existing GSM procedures, except that if the call is answered GMSCA inserts in the ISUP Answer message the destination address which it used to route the call, to allow VMSCA to generate the correct charging record. NOTE: If the GMSC returns an ISUP Answer message before it has received an Answer message from the final destination (e.g. because of an interaction with a Specialised Resource Function) an incorrect destination address (or no destination address) can be sent to VMSCA, even though the call is eventually optimally routed. ETSI