Method and system for support of overlapping IP addresses between an interworking function and a mobile IP foreign agent

Not Applicable A method and system are disclosed for supporting overlapping IP addresses by sharing a mobile node identifier between an IWF and a Foreign Agent in a visited data (e.g., wireless) network. The mobile node identifier is stored in lookup tables associated with the IWF (Mobile Identity table) and the Foreign Agent (Visitor List table). When a data packet travels between the IWF and the Foreign Agent, the mobile node identifier is attached to it. For data packets moving in the reverse Mobile IP traffic direction (from the mobile node), the Foreign Agent uses the mobile node identifier to identify the correct Home Agent destination by finding the corresponding Home Agent address in the Visitor List table. For forward Mobile IP traffic (to the mobile node), the IWF uses the mobile node identifier to identify the correct mobile node destination by finding the corresponding link identifier in the Mobile Identity table.