6a PLMN specific interfaces

23.0023GPPNetwork architectureRelease 17TS

6a.1 GCR-specific interface

6a.1.1 Interface between the MSC and its associated GCR (I-interface)

The GCR is the management data base for the voice group or broadcast calls in the area controlled by the associated MSC(s). Whenever the MSC needs data related to a requested voice group or broadcast call it interrogates the GCR to obtain the respective voice group or broadcast call attributes. The protocol used to transfer the data over this interface is not standardized.

6a.2 (void)

6a.3 LCS-specific interfaces

6a.3.1 LCS interfaces using MAP

The following interfaces are based on MAP in LCS.

– Lh interface: interface between GMLC and HLR. This interface is used by the GMLC to request the address of the visited MSC or SGSN for a particular target UE whose location has been requested (see TS 29.002 [26]).

– Lg interface: interface between GMLC – MSC and GMLC – SGSN. This interface is used by the GMLC to convey a location request to the MSC or SGSN currently serving a particular target UE whose location was requested. The interface is used by the MSC or SGSN to return location results to the GMLC (see TS 29.002 [26]).

– Lc interface: between GMLC and gsmSCF, CAMEL. This interface is used to get location information for CAMEL based services. (see TS 29.002 [26]).

6a.3.2 (void)

6a.3.3 (void)

6a.3.4 (void)

6a.3.5 Interface between BSC and SMLC (Lb-interface)

In GERAN, a SMLC supports positioning via signalling on the Lb interface to the BSC serving the target MS.

Signalling on this interface uses BSSAP-LE, which is specified in TS 49.031 [50]

In UTRAN, the Lb interface is not standardized, the SMLC functionality is included in SRNC.

6a.3.6 Interface between Peer SMLCs (Lp-interface)

In GERAN, a SMLC may support the Lp interface to enable access to information and resources owned by another SMLC.

Signalling on this interface uses BSSAPP-LE, which is defined in TS 49.031 [50], and SMLCPP, which is specified in TS 48.031 [47].

In UTRAN, the SMLC functionality is included in SRNC and the Iur interface shall include the Lp interface type of functionality.

6a.3.7 Interface between BTS and LMU (Um-interface)

The Um/Uu interface specific to LCS is defined in TS 44.071 [55].

6a.3.8 Interface between GMLC and External LCS Client (Le-interface)

The Le interface is used by the external LCS client to retrieve location information from the LCS server. Signalling on this interface may use the OMA Mobile Location Protocol (MLP) [62] and Open Service Access Application Programming Interface (OSA-API), TS 29.198 [63].

6a.3.9 Interface between RNS and Stand-Alone LMU, UE (Uu-interface)

The Uu interface is used to communicate among the UE Positioning entities associated with the SRNC, the UEs and the stand-alone LMU. The Uu interface may pass measurement requests and results to and from the UE or the stand-alone LMU. UE Positioning operations at the Uu interface are generally defined in the 24- and 25-series of 3GPP Technical Specifications. Furthermore, TS 25.305 [10b] describes how a stand-alone LMU may be distinguished from a normal UE.

6a.3.10 Interface between SRNC and SAS (Stand-Alone SMLC) (Iupc-interface)

The Iupc interface defined for LCS is specified in TS 25.453 [66].

6a.3.11 Interface between GMLC and GMLC (Lr-interface)

The Lr interface is used by the GMLC to communicate with other GMLCs. Signalling on this interface may use the OMA Roaming Location Protocol (RLP) [69].

6a.3.12 Interface between GMLC and MME (SLg-interface)

The SLg interface is used by the GMLC to communicate with MMEs. The SLg interface is defined in TS 29.172 [123].

6a.3.13 Interface between MME and E-SMLC (SLs-interface)

The SLs interface is used to convey LCS messages between the MME and E-SMLC. It is also used for tunnelling positioning protocol messages between the E-SMLC and either E-UTRAN or UE which are transparent to the MME as described in TS 36.305 [122]. The SLs interface is defined in TS 29.171 [124].

6a.3.14 Interface between GMLC and HSS (SLh-interface)

SLh interface between GMLC and HSS. This interface is used by the GMLC to request the address of the visited MME for a particular target UE whose location has been requested. The SLh interface is defined in TS 29.173 [125].

6a.3.15 Interface between GMLC and SGSN (Lgd-interface)

Lgd is the interface that is used by the GMLC to convey a location request to the SGSN currently serving a particular target UE whose location was requested. The interface is also used by the SGSN to return location results to the GMLC. This interface is applicable only for an SGSN supporting EPS based interfaces and protocols. The Lgd interface is defined in TS 29.172 [123].

6a.4 CAMEL-specific interfaces

The CAMEL-specific interfaces are detailed in TS 23.078 [10c]. These interfaces are.

6a.4.1 GMSC – gsmSSF interface

This is an internal interface. The interface is described in the specification to make it easier to understand the handling of Detection Points (arming/disarming of DPs, DP processing etc.).

6a.4.2 gsmSSF – gsmSCF interface

This interface is used by the gsmSCF to control a call in a certain gsmSSF and to request the gsmSSF to establish a connection with a gsmSRF. Relationships on this interface are opened as a result of the gsmSSF sending a request for instructions to the gsmSCF.

6a.4.3 MSC – gsmSSF interface

This is an internal interface. The interface is described in the specification to make it easier to understand the handling of DPs (arming/disarming of DPs, DP processing etc.).

6a.4.4 gsmSCF – HLR interface

This interface is used by the gsmSCF to request information from the HLR. As a network operator option the HLR may refuse to provide the information requested by the gsmSCF.

This interface is also used for USSD operations, both for gsmSCF-initiated dialogues and MS-initiated dialogues (relayed via HLR). It is a network operator option whether to support or not USSD operations on this interface.

6a.4.5 gsmSCF – gsmSRF interface

This interface is used by the gsmSCF to instruct the gsmSRF to play tones/announcements to the users.

6a.4.6 MSC – gsmSCF interface

This interface is used by the MSC to send supplementary service invocation notifications to the gsmSCF.

6a.4.7 SGSN – gprsSSF interface

This is an internal interface. The interface is described in the specification to make it easier to understand the handling of DPs (arming/disarming of DPs, DP processing etc.).

6a.4.8 gprsSSF – gsmSCF interface (Ge Reference Point)

This interface is used by the gsmSCF to control a GPRS session or individual PDP Context in a certain gprsSSF. Relationships between the gprsSSF and the gsmSCF (GPRS dialogues) on this interface are opened as a result of the gprsSSF sending a request for instructions to the gsmSCF. This interface is also known as Ge reference point (see TS 23.060 [9a]).

6a.5 CBS-specific interfaces

6a.5.1 Interface between the CBC and RNS (Iu_BC Interface)

The interface between the CBC and the RNS is specified in the 25.41x-series of Technical Specifications.

The CBC-RNS interface is used to carry information concerning:

– the CBS messages itself; and

– CBS delivery parameter.

6a.5.2 Interface between the CBC and MME (SBc Interface)

Reference point between CBC and MME for warning message delivery and control functions. This interface is specified in TS 29.168 [98].

6a.5.3 Interface between the CBC and BSC

The interface between the CBC and the BSC is specified in TS 48.049 [119].

The CBC-BSC interface is used to carry information concerning:

– the CBS message and the warning message itself; and

– CBS message and warning message delivery parameters.

6a.6 Number portability specific interfaces

6a.6.1 IN-based solution

6a.6.1.1 NPDB to MSC interface

Upon receiving an ISUP IAM, the (gateway or visited) MSC send a database query to the NPDB as a result of analysis of the received MSISDN. The MSISDN is included in the query to the NPDB. The NPDB determines whether the MSISDN is ported or not. If not, it responds back to the MSC to continue the normal call setup procedure for MT calls (optionally providing the Routing Number). If it is ported, the NPDB responds back to the MSC with a Routing Number pointing out the Subscription network.

6a.6.2 Signalling Relay-based solution

6a.6.2.1 GMSC to MNP-SRF interface

Upon receiving an ISUP IAM, the gateway MSC sends a routing interrogation to the MNP-SRF, which in turn will perform one of the actions, described in clause 4a.7, depending on the portability status of the subscriber and the network configuration (see TS 23.066 [40]).

6a.6.2.2 MNP-SRF to HLR interface

When the MNP-SRF receives a routing interrogation from the GMSC or an interrogating network entity (non/call related signalling), and it determines that the subscriber is not ported or it has been ported from another network, the MNP-SRF relays the message to the HLR.

6a.7 IM Subsystem Reference Points

6a.7.1 Reference Point HSS – CSCF (Cx Reference Point)

The Cx reference point supports information transfer between CSCF and HSS.

The main procedures that require information transfer between CSCF and HSS are

1) Procedures related to Serving CSCF assignment

2) Procedures related to routing information retrieval from HSS to CSCF

3) Procedures related to authorisation (e.g., checking of roaming agreement)

4) Procedures related to authentication: transfer of security parameters of the subscriber between HSS and CSCF

5) Procedures related to filter control: transfer of filter parameters of the subscriber from HSS to CSCF

Further information on the Cx reference point is provided in TS 23.228 [34].

6a.7.2 Reference Point CSCF – UE (Gm Reference Point)

The Gm reference point supports the communication between UE and IM CN subsystem, e.g. related to registration and session control.

The protocol used for the Gm reference point is SIP (as defined by RFC 3261 [61], other relevant RFC’s, and additional enhancements introduced to support 3GPP´s needs).

6a.7.3 Reference Point MGCF – IMS-MGW (Mn Reference Point)

The Mn reference point describes the interfaces between the MGCF and IMS-MGW in the IMS. It has the following properties:

– full compliance with the H.248 standard functions for IMS – PSTN/PLMN interworking.- flexible connection handling which allows support of different call models and different media processing purposes not restricted to H.323 [54] usage.

– open architecture where extensions/Packages definition work on the interface may be carried out.

– dynamic sharing of IMS-MGW physical node resources. A physical IMS-MGW can be partitioned into logically separate virtual MGWs/domains consisting of a set of statically allocated Terminations.

– dynamic sharing of transmission resources between the domains as the IMS- MGW controls bearers and manage resources according to the H.248 [52] protocols and functions for IMS.

6a.7.4 Reference Point MGCF – CSCF (Mg Reference Point)

The Mg reference point allows the MGCF to forward incoming session signalling (from the circuit switched network) to the CSCF for the purpose of interworking with circuit switched networks.

The protocol used for the Mg reference point is SIP (as defined by RFC 3261 [61], other relevant RFC’s, and additional enhancements introduced to support 3GPP´s needs).

6a.7.5 (void)

6a.7.5a Reference Point AS-MRFC for media control (Cr Reference Point)

The Cr reference point allows interaction between an Application Server and an MRFC for media control.

The Cr reference point enables the MRFC to fetch and cache documents and resources from an Application Server and to return data to an Application Server.

The Cr reference point enables media control protocol requests, responses and notifications to be sent between the MRFC and an Application Server.

Further information on the Cr reference point is provided in TS 23.218 [113].

6a.7.5b Reference Point AS-MRFC for session control (Mr′ Reference Point)

The Mr’ reference point allows interaction between an Application Server and an MRFC for session control without passing through an S-CSCF.

Further information on the Mr’ reference point is provided in TS 23.218 [113].

6a.7.6 Reference Point CSCF – MRFC (Mr Reference Point)

The Mr reference point allows interaction between an S‑CSCF and an MRFC.

The protocol used for the Mr reference point is SIP (as defined by RFC 3261 [61], other relevant RFC’s, and additional enhancements introduced to support 3GPP´s needs).

6a.7.6a Reference Point MRFC – MRFP (Mp Reference Point)

The Mp reference point allows an MRFC to control media stream resources provided by an MRF.

The Mp reference point has the following properties:

– Full compliance with the H.248 [52] standard.

– Open architecture where extensions (packages) definition work on the interface may be carried out.

6a.7.7 Reference Point CSCF – CSCF (Mw Reference Point)

The Mw reference point allows the communication and forwarding of signalling messaging between CSCFs, e.g. during registration and session control.

6a.7.8 (void)

6a.7.8a Reference Point CSCF – MRB (ISC Reference Point)

This interface is used with an MRB operating in In-Line mode and is described further in TS 23.218 [113]). The S‑CSCF receives a session initiation request from an MRB that originated from an Application Server requesting MRF resources and whose destination is an MRF resource identified by the MRB. The S‑CSCF routes the message to the identified MRFC. Subsequent messages in the same session dialog between the AS and MRFC traverse the MRB as well as the S‑CSCF.

6a.7.9 (void)

6a.7.9a Reference Point AS – MRB (Rc Reference Point)

The Rc reference point is used by the AS to request that media resources be assigned to a call when utilizing an MRB in both Query and In-Line modes (as described in TS 23.218 [113]).

6a.7.10 Reference Point CSCF – BGCF (Mi reference point)

This reference point allows the Serving CSCF to forward the session signalling to the Breakout Gateway Control Function for the purpose of interworking to the circuit switched networks.

The Mi reference point is based on external specifications i.e. SIP [61].

6a.7.11 Reference Point BGCF – MGCF (Mj reference point)

This reference point allows the Breakout Gateway Control Function to exchange session signalling message with the Media Gateway Control Function for the purpose of interworking to the circuit switched networks, or for transit scenarios.

The Mj reference point is based on external specifications i.e. SIP [61].

6a.7.12 Reference Point BGCF/IBCF – BGCF (Mk reference point)

This reference point allows the Breakout Gateway Control Function/IBCF to forward the session signalling to another Breakout Gateway Control Function.

The Mk reference point is based on external specifications i.e. SIP [61].

6a.7.13 Reference Point CSCF- SLF (Dx Reference Point)

This interface between CSCF and SLF is used to retrieve the address of the HSS which holds the subscription for a given user or information related to a service.

This interface is not required in a single HSS environment. An example for a single HSS environment is a server farm architecture.

Details are described in TS 23.228 [34], clause 5.8.1.

6a.7.14 Reference Point to IMS media plane (Mb reference point)

The Mb reference point is used for IMS media transport between relevant IMS functions. IMS media is defined in some of the 26-series (e.g. TS 26.114 [143], TS 26.141 [144]).

6a.7.15 Reference Point S‑CSCF – AS (ISC Reference Point)

This interface between Serving CSCF and the Application Servers (i.e., SIP Application Server, OSA Service Capability Server, or CAMEL IM-SSF) is used to provide services for the IMS.

Details are described in TS 23.228 [34], clause 4.2.4.

6a.7.15a Reference Point E-CSCF – EATF (I4 Reference Point)

This is the interface between the Emergency CSCF and the EATF in serving network (i.e. EATF as defined in TS 23.167 [74]), it is used to provide services for emergency sessions.

6a.7.15b Reference Point I-CSCF – EATF (I5 Reference Point)

This is the interface between the Interrogating CSCF and the EATF in serving network (i.e. EATF as defined in TS 23.167 [74]), it is used to provide services for emergency sessions.

6a.7.16 Reference Point HSS – SIP AS or OSA SCS (Sh Reference Point)

The Application Server (SIP Application Server and/or the OSA Service Capability Server) may communicate to the HSS. The Sh interface is used for this purpose. Details are described in TS 23.228 [34], clause 4.2.4.

This reference point is also used to exchange signalling between IP-SM-GW and the HSS for SMSIP delivery.

6a.7.17 Reference Point HSS – CAMEL IM-SSF (Si Reference Point)

The CAMEL Application Server (IM-SSF) may communicate to the HSS. The Si interface is used for this purpose. Details are described in TS 23.228 [34], clause 4.2.4.

6a.7.18 Reference Point UE – AS (Ut Reference Point)

The Ut interface resides between the UE and the SIP Application Server.

The Ut interface enables the user to manage information related to his services. Such as creation and assignment of Public Service Identities, management of authorization policies that are used e.g. by Presence service, conference policy management, etc.

The AS may need to exhibit security related functions for the Ut interface, the details of these security functions are described in TS 33.222 [72].

For the protocol at the Ut reference point HTTP shall be supported.

6a.7.19 Reference Point AS- SLF (Dh Reference Point)

This interface between AS and SLF is used to retrieve the address of the HSS which holds the subscription for a given user.

This interface is not required in a single HSS environment. An example for a single HSS environment is a server farm architecture.

Details are described in TS 23.228 [34], clause 5.8.1.

6a.7.20 Reference Point CSCF/BGCF – IBCF (Mx Reference Point)

The Mx reference point allows the communication and forwarding of signalling messages between a CSCF/BGCF and an IBCF, e.g. during session establishment.

6a.7.21 Reference Point IBCF – TrGW (Ix Reference Point)

This interface is used by the IBCF to control the TrGW, e.g. to request network address translation binding.

6a.7.22 Reference Point I‑CSCF – AS (Ma Reference Point)

This interface between Interrogating‑CSCF and the Application Servers (i.e. SIP Application Server, OSA Service Capability Server, or CAMEL IM-SSF) is used to:

– forward SIP requests destined to a Public Service Identity hosted by an Application Server directly to the Application Server. Details are described in TS 23.228 [34], clause 5.4.12; and

– initiate a request on behalf of a user or Public Service Identity, if the AS has no knowledge of the serving S‑CSCF for that user or Public Service Identity. Details are described in TS 23.228 [34], clause 5.6.5.3.

6a.7.23 Reference Point P‑CSCF – IMS Access Gateway (Iq Reference Point)

The Iq reference point is between the Proxy‑CSCF and the IMS Access Gateway. It conveys the necessary information that is needed to allocate and release transport addresses.

Details are described in TS 23.228 [34], Annex G.

6a.7.23a Reference Point E‑CSCF – LRF (Ml Reference Point)

The Ml reference point allows the E‑CSCF to request the LRF to validate the location information received from the UE, to determine or query the LRF for routing information to emergency centres. Location information may be received from LRF and/or reference key to allow the PSAP to retrieve location at a later stage.

6a.7.24 Reference Point IBCF – IBCF (Ici Reference Point)

The Ici reference point allows two IBCFs to communicate with each other in order to provide the communication and forwarding of signalling messaging between IM CN subsystem networks.

6a.7.25 Reference Point TrGW – TrGW (Izi Reference Point)

The Izi reference point allows two TrGWs to forward media streams between IM CN subsystem networks.

6a.7.26 Void

6a.7.27 Reference Point MSC Server – CSCF (I2 Reference Point)

The I2 reference point is used to route session control signalling between the MSC Server and the IMS, as defined in TS 23.292 [110] and in TS 23.237 [111]. This can be a roaming and inter-operator reference point.

I2 is used to support one or more of the following features:

– An MSC Server enhanced for ICS, as defined in TS 23.292 [110].

– An MSC Server enhanced for ICS and SRVCC, as defined in TS 23.292 [110], TS 23.216 [83] and TS 23.237 [111].

– An MSC Server enhanced for ICS and SRVCC with the MSC Server assisted mid-call feature as defined in TS 23.237 [111].

– An MSC Server enhanced for ICS and SRVCC with the SRVCC for call in alerting phase feature as defined in TS 23.237 [111].

6a.7.28 Reference Point MSC Server – TAS (I3 Reference Point)

The I3 reference point is used between the MSC Server enhanced for ICS and the TAS to interwork CS signalling and communication service setting procedures, as defined in TS 23.292 [110].

6a.7.29 Reference Point ICS UE – SCC AS (I1 Reference Point)

The I1 reference point is used between the ICS UE and the SCC AS for service control signalling over CS access, as defined in TS 23.292 [110].

6a.7.30 Reference Point IBCF – Application Server (AS) (Ms Reference Point)

The Ms reference point is used between an IBCF and an AS for identity attestation, identity signing, and signature verification, as defined in TS 23.228 [34].

6a.8 Void

6a.9 Reference Points for 3GPP/WLAN Interworking

NOTE: With the introduction of Evolved Packet Core System, the 3GPP AAA server and 3GPP AAA Proxy provide a set of different and additional functions as specified in the EPC specific clause of this specification.

6a.9.1 Reference point 3GPP AAA Server – HLR (D’/Gr’ Reference Point)

This is the reference point between the 3GPP AAA server and the HLR up to and including Rel‑4 and the HSS in Rel‑5. The functionality of this reference point is similar to that of the Wx reference point. For more information see TS 23.234 [67].

6a.9.2 Reference point WLAN access network – 3GPP AAA Proxy/Server (Wa Reference Point)

This is the reference point between the WLAN access network and 3GPP AAA Proxy or Server. The AAA protocol on this reference point is used to transport authentication, authorization and charging data.

6a.9.3 Reference point 3GPP AAA Server – 3GPP AAA Proxy (Wd Reference Point)

This is the reference point between the 3GPP AAA Server and Proxy. the purpose of the protocols crossing this reference point is to transport authentication, authorization and related information. For more information see TS 23.234 [67].

6a.9.4 Reference point 3GPP AAA Server/Proxy – WAG (Wg Reference Point)

This is the reference point between the 3GPP AAA server/proxy and WAG. It is used to provide information needed by the WAG to perform policy enforcement functions for authorised users and to transport per-tunnel based charging information from the WAG to the AAA Proxy in roaming scenarios.

6a.9.5 Reference point PDG – packet data networks (Wi Reference Point)

This is the reference point between the PDG and a packet data network. It may be an operator external public or private packet data network or an intra operator packet data network, e.g. for provision of IMS services.

6a.9.6 Reference Point 3GPP AAA Server/Proxy – PDG (Wm Reference Point)

This is the reference point between the 3GPP AAA server/proxy and PDG. The functionality of this reference point is to enable:

– The 3GPP AAA Server/Proxy to retrieve tunnelling attributes and WLAN UE’s IP configuration parameters from/via Packet Data Gateway

– Carrying messages for service authentication and authorization

– Carrying authentication data for the purpose of tunnel establishment, tunnel data authentication and encryption.

For more information see TS 23.234 [67].

6a.9.7 Reference Point WAG – WLAN access network (Wn Reference Point)

This is the reference point between the WAG and the WLAN access network. It is used to force traffic between a WLAN UE and PDG to go through the WAG.

6a.9.8 Reference Point WAG – PDG (Wp Reference Point)

This is the reference point between WAG and PDG. It is used to transport the Wu reference point protocol data packets.

6a.9.9 Reference point WLAN UE – PDG (Wu Reference Point)

This is the reference point between the 3GPP WLAN UE and PDG. The functionality of this reference point is to establish a tunnel between WLAN UE and PDG and to exchange data packets between WLAN UE and PDG.

6a.9.10 Reference point WLAN UE – WLAN access network (Ww Reference Point)

This is the reference point between the 3GPP WLAN UE and WLAN access network. The functionality of this reference point is specified by IEEE and outside the scope of 3GPP.

6a.9.11 Reference point 3GPP AAA Server – HSS (Wx Reference Point)

This is the reference point between the 3GPP AAA server and HSS. The functionality of this reference point is to enable:

– Retrieval of authentication vectors

– Retrieval of WLAN access-related subscriber information (profile)

– Registration of the 3GPP AAA Server of an authorised WLAN user in the HSS

– Indication of change of subscriber profile

– Retrieval of online charging / offline charging function addresses from HSS.

– Retrieval of service related information

For more information see TS 23.234 [67].

6a.9.12 Reference point 3GPP AAA Server – SLF (Dw reference point)

This reference point is between the 3GPP AAA Server and the SLF. The prime purpose of the protocol(s) crossing this reference point is to enable the 3GPP AAA Server to find the address of the HSS which holds the subscriber data for a given user identity in a configuration with multiple separately addressable HSSs.

6a.10 MBMS specific reference points for GPRS

6a.10.1 Reference point GGSN – BM-SC (Gmb Reference Point)

This reference point is used to exchange signalling between GGSN and BM-SC. This represents the network side boundary of the MBMS Bearer Service from a control plane perspective. This includes user specific Gmb signalling and MBMS bearer service specific signalling. The details for this reference point are described in TS 23.246 [70] and TS 29.061 [104].

6a.10.2 Reference point BM-SC – BM-SC (Mz Reference Point)

This reference point is the roaming variant of the Gmb reference point and is used to exchange signalling between a BM-SC in the VPLMN and a BM-SC in the HPLMN. The details for this reference point are described in TS 23.246 [70] and TS 29.061 [104].

6a.10.3 Reference point GGSN – RNS (or BSS Iu mode) (Gmc Reference Point)

This reference point is used between GGSN and RNS (or BSS Iu mode) for MBMS data delivery using IP multicast. The details for this reference point are described in TS 23.246 [70] and TS 29.281 [126].

6a.11 MBMS specific reference points for EPS

6a.11.1 Reference point MBMS‑GW – BM-SC (SGmb Reference Point)

This reference point is used to exchange signalling between MBMS‑GW and BM-SC. This represents the network side boundary of the MBMS Bearer Service from a control plane perspective. This includes MBMS bearer service specific signalling. The details for this reference point are described in TS 23.246 [70] and TS 29.061 [104].

6a.11.2 Reference point MBMS‑GW – BM-SC (SGi-mb Reference Point)

This reference point is used between MBMS‑GW and BM-SC for MBMS data delivery. The details for this reference point are described in TS 23.246 [70] and TS 29.061 [104].

6a.11.3 Reference point MBMS‑GW – MME (Sm Reference Point)

This reference point is used to exchange signalling between MBMS‑GW and MME for MBMS Session Control. The details for this reference point are described in TS 23.246 [70] and TS 29.274 [90].

6a.11.4 Reference point MBMS‑GW – SGSN (Sn Reference Point)

This reference point is used to exchange signalling between MBMS‑GW and S4-SGSN for MBMS Session Control and for MBMS data delivery in point-to-point mode. The details for this reference point are described in TS 23.246 [70] and TS 29.274 [90].

6a.11.5 Reference point MBMS‑GW – E-UTRAN/UTRAN (M1 Reference Point)

This reference point is used between MBMS‑GW and E-UTRAN/UTRAN for MBMS data delivery using IP Multicast. The details for this reference point are described in TS 23.246 [70], TS 29.281 [126] and TS 36.445 [129].

6a.11.6 Reference point MME – MCE (M3 Reference Point)

This reference point is used to exchange signalling between MME and MCE for MBMS Session Control. The details for this reference point are described in TS 23.246 [70], TS 36.300 [78] and TS 36.444 [128].

6a.11.7 Reference point MCE – eNodeB (M2 Reference Point)

This reference point is used to exchange signalling between MCE and eNodeB for MBMS Session Control. The details for this reference point are described in TS 23.246 [70], TS 36.300 [78] and TS 36.443 [127].

6a.11.8 Reference point Content Provider/SCEF – BM-SC (xMB Reference Point)

This reference point is used to exchange signalling between Content Provider and BM-SC, either directly or via SCEF and to exchange application data directly between Content Provider and BM-SC. The details for this reference point are described in TS 26.346 [146].

6a.12 Reference Points for 3GPP Generic User Profile (GUP)

6a.12.1 Reference Point GUP Server – Applications (Rg Reference Point)

The Rg reference point resides between the GUP Server and the Applications.

The Rg reference point allows applications to create, read, modify and delete any user profile data using the harmonized access interface. The GUP Server locates the data repositories responsible of the storage of the requested profile component(s).

The details of the Rg reference point are described in TS 23.240 [71].

6a.12.2 Reference Point GUP Server – HSS and Applications – HSS (Rp Reference Point)

The Rp reference point resides between the GUP Server and the HSS, and between the Applications and the HSS.

The Rp reference point enables the GUP Server and the Applications to access GUP Data Repositories. The HSS is one of the GUP Data Repositories. It stores the IM CN Subsystem user related data.

The details of the Rp reference point are described in TS 23.240 [71].

6a.13 Reference Points for Policy and Charging Control

6a.13.1 Reference Point PCEF – PCRF/H-PCRF/V-PCRF (Gx Reference Point)

This interface provides transfer of policy and charging rules from PCRF to Policy and Charging Enforcement Function Point (PCEF) in the GW (e.g. GGSN, PDN GW). This interface is specified in TS 29.212 [99].

6a.13.2 Reference Point PCRF – Application Function (Rx Reference Point)

This interface allows for dynamic QoS and charging-related service information to be exchanged between the Policy and Charging Rules Function (PCRF) and the Application Function (AF). This information is used by the PCRF for the control of service data flows and IP bearer resources. For more information see TS 23.203 [73].

6a.13.3 Reference Point SPR – PCRF (Sp Reference Point)

This interface allows for the PCRF to request subscription information from the SPR and the SPR to notify the PCRF when the subscription information has changed if the PCRF has requested such notifications. The details associated with the Sp reference point are not specified in this Release.

6a.13.4 Reference Point OCS – PCEF (Gy Reference Point)

This interface allows for the online charging based on the Diameter credit control application between the Online Charging System (OCS) and the PCEF. For more information see TS 32.251 [101] and RFC 4006 [102].

6a.13.5 Reference Point OFCS – PCEF (Gz Reference Point)

This interface allows for the offline charging based on the charging record data transfer between the Offline Charging System (OFCS) and the PCEF. For more information see TS 32.295 [109].

6a.13.6 Reference Point Trusted non-3GPP IP Access and PCRF/VPCRF (Gxa Reference Point)

This interface provides transfer of (QoS) policy information from PCRF to the Trusted Non-3GPP accesses. This interface is specified in TS 29.212 [99]..

6a.13.7 Reference Point ePDG and PCRF/VPCRF (Gxb Reference Point)

This interface is not specified within this release of the specification.

6a.13.7a Reference Point ePDG and PCRF/VPCRF (Gxb* Reference Point)

The reference point transports access information from ePDG to PCRF/vPCRF for WLAN UEs such as the UE local IP address and the UDP port number. This interface is specified in TS 29.212 [99].

Gxb* is only applicable to the interworking with Fixed Broadband Access network.

6a.13.8 Reference point between S-GW and PCRF/VPCRF (Gxc-interface)

This interface provides transfer of (QoS) policy information from PCRF to the Serving Gateway, Gxc is used only in the case of PMIP-based S5/S8. This interface is specified in TS 29.212 [99]..

6a.13.9 Reference Point PCRF/VPCRF – BBERF (Gxx Reference Point)

This interface allows for a PCRF to have a dynamic control over the Bearer Binding and Event Report Function (BBERF) behaviour. For more information see TS 23.402 [77] and TS 23.203 [73]. This interface is specified in TS 29.213 [92]

6a.13.10 Reference Point HPCRF – VPCRF (S9- interface)

This interface provides transfer of policy and charging rules (in case of local breakout of traffic) and/or (QoS) policy information (when Gxx interface applies) between the Home PCRF and the Visited PCRF in order to support PCC roaming related functions. This interface is specified in TS 29.215 [103].

6a.13.11 Reference Point UDR – PCRF (Ud Reference Point)

This interface allows for the PCRF, acting as an UDC Application Frontend as defined in TS 23.335 [120], to request subscription information from the UDR and the UDR to notify the PCRF when the subscription information has changed if the PCRF has requested such notifications. For details regarding the Ud reference point see TS 23.335 [120] and TS 29.335 [121].

6a.13.12 Reference Point TDF – PCRF/H-PCRF/V-PCRF (Sd Reference Point)

The Sd Reference Point enables a PCRF to have dynamic control over the application detection and control behaviour at a TDF. The Sd Reference Point is specified in TS 29.212 [99].

6a.13.13 Reference Point OCS – PCRF/H-PCRF (Sy Reference Point)

The Sy Reference Point enables transfer of information relating to subscriber spending from OCS to PCRF. The Sy Reference Point is specified in TS 29.219 [131].

6a.13.14 Reference Point HNB GW – PCRF/V-PCRF (S15 Reference Point)

This reference point supports the initiation, modification and termination of sessions between the HNB GW and PCRF to support CS sessions. It triggers the PCRF to request allocation of resources in the Fixed Broadband access network for HNB CS calls. This interface is specified in TS 29.212 [99].

S15 is only applicable to the interworking with Fixed Broadband Access network.

6a.13.15 Reference Point BPCF – PCRF/v-PCRF (S9a Reference Point)

This interface supports the transfer of (QoS) policy information from PCRF to BPCF of broadband access network. This interface is specified in TS 29.215 [103].

S9a is only applicable to the interworking with Fixed Broadband Access network.

6a.13.16 Reference Point OCS – TDF (Gyn Reference Point)

The Gyn Reference Point allows for the online charging based on the Diameter credit control application between the Online Charging System (OCS) and the TDF. For more information see TS 32.251 [101] and RFC 4006 [102].

6a.13.17 Reference Point OFCS – TDF (Gzn Reference Point)

The Gzn Reference Point allows for the offline charging based on the charging record data transfer between the Offline Charging System (OFCS) and the TDF. For more information see TS 32.295 [109].

6a.13.18 Void

6a.13.19 Reference Point TSSF – PCRF/H-PCRF (St Reference Point)

The St Reference Point enables a PCRF to have dynamic control over the traffic steering behaviour at a TSSF. The St Reference Point is specified in TS 29.212 [99].

6a.13.20 Reference point between PFDF and PCEF (Gw reference point)

The Gw reference point enables the PFDF to provide PFDs to the PCEF as described in TS 23.203 [73].

6a.13.21 Reference point between PFDF and TDF (Gwn reference point)

The Gwn reference point enables the PFDF to provide PFDs to the TDF as described in TS 23.203 [73].

6a.14 SMSIP specific reference points

6a.14.1 Reference point IP-SM-GW – HSS (J Reference Point)

This reference point is used to exchange signalling between IP-SM-GW and the HSS for SMSIP delivery. The details for this reference point are described in TS 23.204 [75].

6a.15 User Data Convergence specific reference points

6a.15.1 Reference point Application Front Ends – UDR (Ud Reference Point)

This reference point is used to exchange user between Application Front Ends and the UDR. The details for this reference point are described in TS 23.335 [120] and TS 29.335 [121].

6a.16 Specific reference points for facilitating communications with packet data networks and applications

6a.16.1 Reference point MTC-IWF – SCS (Tsp reference point)

This reference point is used between the MTC-IWF and the Services Capability Server (SCS) to invoke specific functionalities in the PLMN such as device triggering. The details for this reference point are described in TS 23.682 [132] and TS 29.368 [136].

This interface is a PLMN internal interface if the SCS is controlled by the operator.

Signalling on this interface uses Diameter Tsp Application as specified in TS 29.368 [136].

NOTE: See clause 7.8 when the SCS is not controlled by the operator.

6a.16.2 Reference point MTC-IWF – HSS/HLR (S6m reference point)

This reference point is used between the MTC-IWF and the HSS/HLR to authorize a certain SCS to request a specific service (e.g. device triggering), and to retrieve subscription information and routing information (i.e. serving SGSN/MME/MSC identities) from the HSS/HLR.

The details for this reference point are described in TS 23.682 [132] and TS 29.336 [133].

Signalling on this interface uses Diameter S6m Application as specified in TS 29.336 [133].

6a.16.3 Reference point MTC-AAA – HSS/HLR (S6n reference point)

This reference point is used between the MTC-AAA and the HSS/HLR to translate an IMSI to external identifier(s) of the user.

The details for this reference point are described in TS 23.682 [132] and TS 29.336 [133].

Signalling on this interface uses Diameter S6n Application as specified in TS 29.336 [133].

6a.16.4 Reference point MTC-IWF – SMS-SC (T4 reference point)

This reference point is used between the MTC-IWF and the SMS-SC to transfer device trigger to the SMS-SC inside the HPLMN.

The details for this reference point are described in TS 23.682 [132] and TS 29.337 [134].

Signalling on this interface uses Diameter T4 Application as specified in TS 29.337 [134].

6a.16.5 Reference point between the HSS and the SCEF (S6t reference point)

The S6t reference point is defined between the SCEF and the HSS. It provides general access to the capabilities and data of the HSS from the SCEF, including configuration and reporting of specific monitoring events.

The details for this reference point are described in TS 23.682 [132].

6a.16.6 Reference point between the MME and the SCEF (T6a reference point)

The T6a reference point is defined between the SCEF and the MME. It provides general access to the capabilities of the MME from the SCEF, including configuration and reporting of specific monitoring events.

The details for this reference point are described in TS 23.682 [132].

6a.16.7 Reference point between the SGSN and the SCEF (T6b reference point)

The T6b reference point is defined between the SCEF and the SGSN. It provides general access to the capabilities of the SGSN from the SCEF, including configuration and reporting of specific monitoring events.

The details for this reference point are described in TS 23.682 [132].

6a.16.8 Reference point between the RCAF and the SCEF (Ns reference point)

The Ns reference point is defined between the SCEF and the RCAF. It allows the SCEF to request and consequently be notified of the network status.

The details for this reference point are described in TS 23.682 [132].

6a.16.9 Reference point between the PCRF and the SCEF (Nt reference point)

This reference point allows for negotiation about the recommended time window(s) and the related conditions for future background data transfer between the Policy and Charging Rules Function (PCRF) and the Service Capability Exposure Function (SCEF). For more information see TS 23.203 [73].

6a.16.10 Reference point between the PFDF and the SCEF (Nu reference point)

This reference point enables the Service Capability Exposure Function (SCEF) to manage Packet Flow Descriptions (PFDs) in the Packet Flow Description Function (PFDF) according to the instructions received from the SCS/AS. For more information see TS 23.682 [132].

6a.17 GCSE_LTE specific reference points

6a.17.1 Reference point GCS AS – BM-SC (MB2 Reference Point)

This reference point is used to exchange signalling and application data between BM-SC and GCS AS. This includes start, stop, and modification of MBMS broadcast bearer service. The details for this reference point are described in TS 23.468 [140].

6a.17.2 Reference point GCS AS – UE (GC1 Reference Point)

This reference point is used to exchange signalling and application data between GCS AS and UE. The details for this reference point are described in TS 23.468 [140].

6a.18 ProSe specific reference points

6a.18.1 Reference point UE – ProSe Application Server (PC1 Reference Point)

This reference point is used to define application level signalling requirements. This reference point is not specified in this release of the specification. The details for this reference point are described in TS 23.303 [141].

6a.18.2 Reference point ProSe Function – ProSe Application Server (PC2 Reference Point)

This reference point is used to define the interaction between ProSe Application Server and ProSe functionality provided by the 3GPP EPS via ProSe Function (e.g. name translation) for EPC-level ProSe discovery. The details for this reference point are described in TS 23.303 [141].

6a.18.3 Reference point UE – ProSe Function (PC3 Reference Point)

This reference point relies on EPC user plane for transport (i.e. an "over IP" reference point). It is used to authorise ProSe Direct Discovery and EPC-level ProSe Discovery requests, and perform allocation of ProSe Application Codes corresponding to ProSe Application Identities used for ProSe Direct Discovery. It is used to define the authorisation policy per PLMN for ProSe Direct Discovery (for Public Safety and non -Public Safety) and communication (for Public Safety only) between UE and ProSe Function. The details for this reference point are described in TS 23.303 [141].

6a.18.4 Reference point HSS – ProSe Function (PC4a Reference Point)

The reference point is used to provide subscription information in order to authorise access for ProSe Direct Discovery and ProSe Direct Communication on a per PLMN basis. It is also used by the ProSe Function (i.e. EPC-level ProSe Discovery Function) for retrieval of EPC-level ProSe Discovery related subscriber data. The details for this reference point are described in TS 23.303 [141].

6a.18.5 Reference point SLP – ProSe Function (PC4b Reference Point)

The reference point is used by the ProSe Function (i.e. EPC-level ProSe Discovery Function) (in the role of LCS client to query the SLP defined in OMA AD SUPL [80]. The details for this reference point are described in TS 23.303 [141].

6a.18.6 Reference point UE – UE (PC5 Reference Point)

This reference point is between ProSe-enabled UEs used for control and user plane for ProSe Direct Discovery, ProSe Direct Communication and ProSe UE-to-Network Relay. The details for this reference point are described in TS 23.303 [141].

6a.18.7 Reference point ProSe Function – ProSe Function in different PLMNs (PC6 Reference Point)

This reference point is between ProSe Functions in different PLMNs (EPC-level ProSe Discovery) or between the ProSe Function in the HPLMN and the ProSe Function in a Local PLMN (ProSe Direct Discovery). With ProSe Direct Discovery this reference point is used for HPLMN control of ProSe service authorization. It is also used to authorise ProSe Direct Discovery requests, retrieve the Discovery Filter(s) corresponding ProSe Application ID name(s) and translate the ProSe Application Code to the ProSe Application ID Name. The details for this reference point are described in TS 23.303 [141].

6a.18.8 Reference point ProSe Function in HPLMN – ProSe Function in VPLMN (PC7 Reference Point)

This reference point is between the ProSe Function in the HPLMN and the ProSe Function in the VPLMN. It is used for HPLMN control of ProSe service authorization. It is also used to authorise ProSe Direct Discovery requests, retrieve the Discovery Filter(s) corresponding ProSe Application ID name(s) and translate the ProSe Application Code to the ProSe Application ID Name. The details for this reference point are described in TS 23.303 [141].

6a.19 Reference points for RAN user plane congestion detection and reporting

6a.19.1 Reference Point RCAF – PCRF/ V-PCRF (Np Reference Point)

The Np Reference Point enables transport of RAN User Plane Congestion Information sent from the RCAF to the PCRF. The Np Reference Point is specified in TS 23.203 [73].

6a.19.2 Reference point between MME and RCAF (Nq reference point)

The Nq reference point enables the RCAF to retrieve the list of UEs (identified by the IMSIs) served by an eNodeB or E-UTRAN cell and the list of APNs of the active PDN connections of each IMSI. The Nq reference point is specified in TS 23.401 [76].

6a.19.3 Reference point between SGSN and RCAF (Nq’ reference point)

The Nq’ reference point enables the RCAF to retrieve the list of APNs of the active PDN connections of a given UE (identified by the IMSI). The Nq’ reference point is specified in TS 23.060 [9a].