Patent ID: 8457114

Claim:
A method of establishing a telecommunication session with a mobile satellite terminal having an IP Multimedia System (IMS) client, comprising: establishing an IMS Packet Data Protocol (PDP) context activation by a Proxy Call Session Control Function (P-CSCF) associated with the calling User Equipment (UE) prior to exchanging any Session Initiation Protocol (SIP) signaling with a proxy associated with the called UE, wherein the establishing the IMS PDP context activation comprises initiating a Network Requested Secondary PDP Context Activation (NRSPCA) on Offer by sending a Packet Data Protocol (PDP) context activation request to a Gateway GPRS Service node (GGSN) associated with the calling UE and withholding an acknowledgement to the P-CSCF until receiving an indication of a successful activation from the GGSN; and using a High Penetration Alert (HPA) directed to the called UE only if the called UE subscribes to a HPA service, and only for calls having a conversational or interactive traffic class.