scope:

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 indirect communication between the 5G network and UEs (e.g. for UEs that are out of coverage of the network).

Security aspects of ProSe in 5GS are defined in TS 33.503 [29].