7C Requirements for relay UE selection for Evolved ProSe Remote UE access via an Evolved ProSe UE-to-Network Relay

22.2783GPPService requirements for the Evolved Packet System (EPS)TS

7C.1 General

At the time of remote UE selection of Evolved ProSe UE-to-Network Relay, there might be several Evolved ProSe UE-to-Network Relay capable UEs in proximity of the Evolved ProSe Remote UE, and available for discovery and relay connection establishment. The requirements listed in the following sub-sections relate to the selection of an appropriate Evolved ProSe UE-to-Network Relay to be used for Evolved ProSe Remote UE access to a 3GPP PLMN.

The 3GPP system shall support selection of one out of potentially several Evolved ProSe Relay capable UEs, in proximity of the Evolved ProSe Remote UE and available for discovery and relay connection establishment, through a 3GPP defined relay UE selection procedure.

The 3GPP system shall support selection of Evolved ProSe UE-to-Network Relays with subscriptions with the same owner as the subscription of the Evolved ProSe Remote UE as well as Evolved ProSe UE-to-Network Relays with subscriptions with a different owner than the subscription of the Evolved ProSe Remote UE.

The 3GPP system shall support pairing of an Evolved ProSe Remote UE and a specific Evolved ProSe UE-to-Network Relay to allow for fast remote connectivity setup with UE consent given, and/or MNO control applied, at the time of pairing.

7C.2 Relay UE selection

The 3GPP system shall support selection of an Evolved ProSe UE-to-Network Relay based on a combination of different criteria e.g.,

  • the subcriptions of Evolved ProSe UE-to-Network Relay and Evolved ProSe Remote UE,
  • the capabilities of the Evolved ProSe UE-to-Network Relay,
  • the QoS that is achieveable by selecting the Evolved ProSe UE-to-Network Relay,
  • the power consumption required by Evolved ProSe UE-to-Network Relay UE and Evolved ProSe Remote UE,
  • the pre-paired Evolved ProSse UE-to-Network Relay,
  • the 3GPP or non-3GPP access the Evolved ProSe UE-to-Network Relay uses to connect to the network, or
  • the 3GPP PLMN the Evolved ProSe UE-to-Network Relay connects to.

NOTE: Other criteria can play a role in selection of an Evolved ProSe UE-to-Network Relay.

The 3GPP network shall be able to control Evolved ProSe UE-to-Network Relay selection either explicitly (e.g. by signalling) or implicitly (e.g. by provisioning of policies in the Evolved ProSe Remote UE and Evolved ProSe UE-to-Network Relay).

The 3GPP system shall support pre-configuration of Relay UE discovery information in addition to pre-configured PLMN selection information, needed for Relay UE selection, in the Evolved ProSe Remote UEs. It should include the applicable Relay UE identity to allow identification of to which Evolved ProSe Relay UE a specific set of information applies.

The 3GPP system shall support provisioning of information in the Evolved ProSe Remote UE (ME and/or USIM) used for relay UE selection.

The 3GPP system shall support having preferences stored in the Evolved ProSe Remote UE related to the relay UE selection criteria, configured/controlled by the home operator, user selectable, or a combination of both.

The 3GPP system shall support mechanisms for allowing an Evolved ProSe Remote UE to get information regarding which PLMN a specific Evolved ProSe UE-to-Network Relay connects to, prior to indirect 3GPP connection establishment.

The 3GPP system shall support mechanisms for allowing an Evolved ProSe Remote UE to get information regarding what PLMNs a specific Evolved ProSe UE-to-Network Relay connects to, in case of network sharing, prior to indirect 3GPP connection establishment.