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

1. 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, wherein said 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 is performed by a serving gateway node of the target network.

2. The method of claim 1 , wherein the connection request message establishes the presence of the user equipment with the target network and comprises an indication that multiple PDN connections are currently in use by the user equipment.

3. The method of claim 1 , wherein the first node comprises a high rate packet data (HRPD) node.

4. The method of claim 1 , wherein the one or more nodes of the target network comprises an access network node and a serving gateway node.

5. The method of claim 1 , wherein said receiving the connection request message is performed by an access network node of the target network.

6. The method of claim 1 , wherein the AAA server is coupled with a home subscriber storage (HSS) entity on the home network.

7. The method of claim 1 , wherein the address information for the PDN gateways also includes all IP addresses of the PDN gateways with corresponding PDN information.

8. The method of claim 1 , wherein the connection request message is a high rate packet data (HRPD) connection request message.

9. The method of claim 1 , wherein the source network and the home network are the same.

10. 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, wherein said 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 is performed by a serving gateway node of the target network.

11. The target communications network of claim 10 , wherein the connection request message establishes the presence of the user equipment with the target network and comprises an indication that multiple PDN connections are currently in use by the user equipment.

12. The target communications network of claim 10 , wherein the first node comprises a high rate packet data (HRPD) node.

13. The target communications network of claim 10 , wherein receiving the connection request message is performed by an access network node of the target network.

14. The target communications network of claim 10 , wherein the AAA server is coupled with a home subscriber storage (HSS) entity on the home network.

15. The target communications network of claim 10 , wherein the address information for the PDN gateways also includes all IP addresses of the PDN gateways with corresponding PDN information.

16. The target communications network of claim 10 , wherein the connection request message is a high rate packet data (HRPD) connection request message.

17. The target communications network of claim 10 , wherein the source network and the home network are the same.