Section: P.2 Session management and traffic routing for PIN
Content: The general session management principles as described in clause 5.6, the QoS model as defined in clause 5.7 and the User Plane management for 5GS as defined in clause 5.8 are applicable to PIN-DN communication and PIN-indirect communication. If a PIN has multiple PEGC UEs, 5G VN group communication mechanisms can be used for PIN indirect communication (i.e. communication between PIN Elements belonging to the same PIN but served by different PEGC UEs). In this case a dedicated SMF set is used for managing the PIN related PDU Sessions from all the PEGCs of that PIN and the PDU session management principles for 5G VN-LAN-type services as specified in clause 5.29.3 are applicable. The user plane handling for 5G LAN-type services as specified in 5.29.4 are applicable with following differences: - For PIN indirect communication N19-based traffic forwarding is not used i.e. the PIN traffic is forwarded using: - N6-based traffic forwarding method, where the UL/DL traffic for the PIN communication is forwarded to/from the DN; - local switching as depicted in Figure P.2-1 below, following the principles of local switching of traffic for 5G VN LAN-type service. Figure P.2-1: Local-switch based user plane architecture for PIN NOTE: Figure P.2-1 does not show traffic from a PEMC. The SMF configures the UPF(s) to apply N6-based traffic forwarding to route traffic between PDU Sessions of different PEGC UEs of a PIN as specified in clause 5.8.2.13. The SMF can apply local switching as specified in clause 5.8.2.13 in order to enable UPF locally forward uplink stream from one PDU session of one PEGC UE of a PIN as downlink stream of PDU session of one or more PEGC UE(s) of the same PIN. For local switching of PIN traffic between PIN related PDU sessions from different PEGC UEs of a single PIN, based on the DNN and S-NSSAI that is used for the PDU session related to PIN, the SMF provides a Network Instance to the UPF in FAR and/or PDR via N4 Session Establishment/Modification procedures.