Method and System for Maintaining Multiple PDN Network Connection During Inter-Technology Handover in the Idle Mode

A method for maintaining connectivity between user equipment and multiple packet data network (PDN) connections during an idle mode handover from a source network operating under the 3GPP communications protocol to a target network operating under a non-3GPP communications protocol, comprising the steps of:

• at one or more nodes of the target network:
• receiving a connection request message from the user equipment;
• transmitting a request message to an authentication, authorization, and accounting (AAA) server on a home network assigned to the user equipment;
• receiving a response message from the AAA server on the home network assigned to the user equipment, wherein the response message comprises the addresses for all PDN gateways currently in use by the user equipment;
• using the addresses for all PDN gateways currently in use by the user equipment to exchange messages with the PDN gateways to maintain PDN connections with the user equipment after handover of user equipment communications to the target network.

A target communications network operating under a non-3GPP communications protocol used to maintain connectivity between user equipment and multiple PDN connections during an idle mode handover, comprising:

• an access network node;
• and
• a serving gateway node coupled to the access network node;
• wherein at least the access network node and the serving gateway node are configured to operate together to:
• receive a connection request message from the user equipment;
• transmit a request message to an authentication, authorization, and accounting (AAA) server on a home network assigned to the user equipment;
• receive a response message from the AAA server on the home network assigned to the user equipment, wherein the response message comprises the addresses for all PDN gateways currently in use by the user equipment;
• use the addresses for all PDN gateways currently in use by the user equipment to exchange messages with the PDN gateways to maintain PDN connections with the user equipment after handover of user equipment communications to the target network.