PC1:
The reference point between the ProSe application in the UE and in the ProSe Application Server. It is used to define application level signalling requirements. This reference point is not specified in this release of the specification.
PC2:
The reference point between the ProSe Application Server and the ProSe Function. It 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 ProSe Direct Discovery and EPC-level ProSe discovery.
PC3:
The reference point between the UE and the ProSe Function. PC3 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 / ProSe Restricted 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.
PC4a:
The reference point between the HSS and ProSe Function. It 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.
PC4b:
The reference point between the SUPL Location Platform (SLP) defined in
OMA AD SUPL [2] and the ProSe Function. It 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 [2].
PC5:
The reference point between ProSe-enabled UEs used for control and user plane for ProSe Direct Discovery, ProSe Direct Communication and ProSe UE-to-Network Relay. The lower protocol layers of the PC5 reference point can be based on E-UTRA sidelink capabilities specified in
TS 36.300 or on WLAN technology.
PC6:
The reference point 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.
PC7:
The reference point 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.
S6a:
In addition to the relevant functions defined in
TS 23.401 for S6a, in case of ProSe S6a is used to download ProSe related subscription information to MME during E-UTRAN attach procedure or to inform MME subscription information in the HSS has changed.
S1-MME:
In addition to the relevant functions defined in
TS 23.401 for S1-MME, in case of ProSe it is also used to convey the ProSe direct services authorization from MME to eNodeB.