Patent ID: 9036554
Filing Date: 2015-05-19
Classification: H04L,H04M,H04W

Abstract:
1. A method of participating in an Internet Protocol (IP) Multimedia Subsystem (IMS) registration and session initiation for a user equipment (UE), the UE having a subscription identifier comprising at least one of a IMSI and a MSISDN, the method comprising: establishing, by a packet data network gateway (PDN-GW), an IP connectivity access network (IP-CAN) session with a policy and charging rules function (PCRF) for the UE, by transmitting, to the PCRF, at least binding, by the PCRF, the subscription identifier to the IP address assigned to the UE for the IP-CAN session; upon the UE initiating the IMS registration, transferring, from a proxy call session control function (P-CSCF) to a serving call session control function (S-CSCF) an IP multimedia public identity (IMPU); obtaining, by the S-CSCF, based on the IMPU, the subscription identifier of the UE from a user database; transferring, by the S-CSCF to the P-CSCF, the obtained subscription identifier of the UE; binding, by the P-CSCF, the transferred subscription identifier of the UE to the IMPU; upon the UE initiating an IMS session associated with the IMPU, establishing, by the P-CSCF, an application function session towards the PCRF with the subscription identifier bound to the IMPU; and identifying, by the PCRF, the correct IP-CAN session by matching the received subscription identifier with the subscription identifier of the IP-CAN session.