Patent ID: 8064404

Claim:
A method of a wireless network allowing a client device to roam from a home subnet to a foreign subnet of the network, comprising: a first access node of the home subnet of the network providing the client device wireless access to the network; each gateway of the network maintaining a list of other gateways on a plurality of subnets of the network wherein gateways of different subnets are connected to different edge routers, the list comprising an IP address of each of the other gateways, a gateway status of each of the other gateways, and at least one subnet associated with each of the other gateways; a foreign gateway of the foreign subnet forming an IP-in-IP tunnel to a home gateway of the home subnet allowing the client device to roam to a second access node of the foreign subnet, the client device wirelessly accessing the network through the second access node, the client device maintaining a fixed client IP address, default gateway IP address and IP subnet attachment as the client device roams from the first access node to the second access node; resolving the fixed client IP address of the client device from a MAC address of the client device, wherein resolving the fixed client IP address comprises: the foreign gateway of the foreign subnet sending a request to designated gateways of all other subnets of the network; the foreign gateway periodically checking a status of the home gateway, wherein the home gateway is connected to a different edge router than the foreign gateway; the home gateway receiving a relayed DHCP request; and the home gateway relaying the DHCP request to a local DHCP server.