The present document specifies the Stage 2 of the Proximity based Services (ProSe) features in 5GS. 5G ProSe features consist of: 5G ProSe Direct Discovery, 5G ProSe Direct Communication and 5G ProSe UE-to-Network Relay.
5G ProSe Direct Discovery identifies that 5G ProSe-enabled UEs are in proximity using NR.
5G ProSe Direct Communication enables establishment of communication paths between two or more 5G ProSe-enabled UEs that are in direct communication range using NR.
5G ProSe UE-to-Network Relay enables relay communication between NG-RAN and UEs (e.g. for UEs that are out of coverage of the network).
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. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.
For the purposes of the present document, the terms given in TR 21.905 and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905.
5G ProSe-enabled UE:
A UE that supports 5G ProSe requirements and associated procedures.
5G ProSe Direct Discovery:
A procedure employed by a 5G ProSe-enabled UE to discover other 5G ProSe-enabled UEs in its vicinity based on direct radio transmissions between the two UEs with NR technology.
5G ProSe Direct Communication:
A communication between two or more UEs in proximity that are 5G ProSe-enabled, by means of user plane transmission using NR technology via a path not traversing any network node.
5G ProSe UE-to-Network Relay:
A 5G ProSe-enabled UE that provides functionality to support connectivity to the network for 5G ProSe Remote UE(s).
5G ProSe Remote UE:
A 5G ProSe-enabled UE that communicates with a DN via a 5G ProSe UE-to-Network Relay.
Application Layer ID:
An identity identifying a 5G ProSe-enabled UE within the context of a specific application. The format of this identifier is outside the scope of 3GPP.
Direct Network Communication:
One mode of network communication, where there is no 5G ProSe UE-to-Network Relay between a UE and the 5G network.
Indirect Network Communication:
One mode of network communication, where there is a 5G ProSe UE-to-Network Relay between a UE and the 5G network.
An identifier uniquely identifying a member in the Application Layer managed group and that is managed by the ProSe application layer.
Mode of communication:
Mode of communication to be used by the 5G ProSe-enabled UE over PC5 reference point, i.e. broadcast mode, groupcast mode or unicast mode.
Open ProSe Discovery:
ProSe Direct Discovery without explicit permission from the 5G ProSe-enabled UE being discovered, according to TS 22.278.
An identifier used to indicate the ProSe Application associated with the ProSe operation in ProSe Direct Discovery and ProSe Direct Communication. A ProSe identifier can be associated with one or more ProSe applications, and a ProSe application can be associated with one or more ProSe identifier(s). For ProSe Direct Discovery, ProSe identifier is equivalent to "Application ID" defined in 23.303 .
Restricted ProSe Discovery:
ProSe Direct Discovery that only takes place with explicit permission from the 5G ProSe-enabled UE being discovered, according to TS 22.278.
User Info ID:
The User Info ID is configured for Model A or Model B Group Member Discovery and 5G ProSe UE-to-Network Relay Discovery either for public safety or commercial applications based on the policy of the HPLMN or via the ProSe application server that allocates it. The User Info ID is sent by the announcing or discoverer or discoveree UE over the air. The definition of values of User Info ID is out of scope of this specification.
For the purposes of the present document, the following term and definition given in TS 23.303 apply:
Application Layer Group ID
Destination Layer-2 ID
Discovery Entry ID
Discovery Query Filter
Discovery Response Filter
Metadata Index Mask
ProSe Application ID
ProSe Application Code
ProSe Application Mask
ProSe Query Code
ProSe Response Code
ProSe Restricted Code
ProSe Restricted Code Prefix
ProSe Restricted Code Suffix
ProSe Discovery UE ID
ProSe Layer-2 Group ID
Restricted ProSe Application User ID
Source Layer-2 ID
For the purposes of the present document, the abbreviations given in TR 21.905 and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905.