Methods and apparatus for implementing a Home Agent supporting Mobile IP and being capable of allocating one or more networks to a mobile router which registers with the Home Agent comprise receiving a registration request packet from the mobile router, the registration request packet including a network allocation extension indicating one or more networks being requested by the mobile router from the Home Agent. The one or more networks are allocated to the mobile router corresponding to the network allocation extension of the registration request packet. A registration reply packet including a network allocation extension identifying the one or more networks allocated to the mobile router is then sent to the mobile router.