home agent (mobile IP) (HA)

The term home agent(HA) plays a role in Mobile- IP when roaming between radio cells as well as when roaming between mobile networks and WLANs.

The home agent is a function of the router that manages the changing network node addresses of the mobile end devices, the mobile nodes( NM), in mobile networks and WLANs. These change constantly as the mobile device moves from the home network( HN) to a foreign network. Binding updates constantly inform the home agent about the current IP address of the mobile terminal.

The home agent receives the IP packets sent to the home address - which is the permanent IP address of the mobile node - and tunnels them on to the temporary IP address using care-of address.