4.4 Gateway Control Session Procedures

29.2133GPPPolicy and charging control signalling flows and Quality of Service (QoS) parameter mappingRelease 17TS

There are two kinds of Gateway Control (GC) sessions:

– A Gateway Control session that serves a single IP-CAN session (e.g. S-GW/BBERF connecting to PDN-GW using S5/S8 PMIP according to 3GPP TS 23.402 [21]).

– A Gateway Control session that serves all the IP-CAN sessions from the same Care-of address of the UE (e.g. a UE connecting to PDN-GW using S2c according to 3GPP TS 23.402 [21]).

These Gateway Control sessions are initiated in connection with IP-CAN session establishment and Initial Attach respectively. For the first case, the PCRF will identify that the GC session serves a single IP-CAN session based on the PDN Identifier received in the request.

An access network may support mobility with BBERF change. The new BBERF shall establish new Gateway Control sessions according to the procedures defined for the new access type and the PCRF shall correlate those sessions with ongoing IP-CAN sessions as part of the handover procedure.

These scenarios are shown separately in different flows.

In the following procedures, the V-PCRF is included to depict the roaming scenarios. H-PCRF will act as a PCRF for non-roaming Ues. The procedure to detect that the IP-CAN Session is restricted to Emergency Services is described in 3GPP TS 29.212 [9].