foreign agent (FA)

The foreign agent (FA) is a router in WLANs and mobile networks that cooperates with the mobile terminals, referred to as mobile nodes(MNs) in the case of mobile IP.

The foreign agent (FA) performs the routing functions for the mobile node to foreign networks. In functional terms, this involves forwarding routing requests between the mobile node and the home agent( HA). If a care-of address( CoA) is provided by the foreign agent for the mobile node, then it forwards traffic to the mobile device. It also acts as a relay between the mobile node and its home agent for registration requests.