Patent ID: 7630352

Claim:
A Foreign Agent that supports Mobile IP, the Foreign Agent being capable of registering a mobile device with a Home Agent in an asymmetric link environment, the Foreign Agent comprising: a processor; and a memory, at least one of the processor or the memory being adapted for: associating each one of a plurality of interfaces of the Foreign Agent with a different care-of address such that each of the plurality of interfaces is mapped to a different care-of address; sending at least one agent advertisement including the care-of address for each of the plurality of interfaces of the Foreign Agent via one or more uplinks; receiving a registration request forwarded via a downlink router, the registration request identifying a care-of address associated with only one of the plurality of interfaces of the Foreign Agent; ascertaining the one of the plurality of interfaces identified by the care-of address in the registration request, thereby identifying the interface to which the mobile device has roamed; forwarding the registration request to the Home Agent; receiving a registration reply from the Home Agent; and forwarding the registration reply to the mobile device via the ascertained interface.