Patent ID: 7814541
Filing Date: 2010-10-12
Classification: H04L

Abstract:
1. A method of virtual routing an overlapping IP address for a virtual private network (VPN) device connected to a virtual local area network (VLAN) without affecting Internet protocol (IP) processing within the VPN device, the method comprising: receiving on the VPN device, a packet with an overlapping Internet protocol (IP) address from a virtual site, the overlapping IP address having a virtual site tag associated with it; converting the overlapping IP address into a non-overlapping unique IP address by a virtual network address layer (VNAT) upon reception, so that Internet Protocol (IP) processing within the VPN device is not affected in a demilitarized zone of the VPN device; performing internet protocol processing within the VPN device on the packet using the non-overlapping unique IP address; converting the non-overlapping unique IP address back to the overlapping IP address having a virtual local area network tag by a virtual LAN (local area network) aware NAT (Network Address Translaton) layer within the VPN device to provide a mapping function, and wherein the mapping function returns a valid IP address only if the virtual site address tag in question has a local area network tag, which contains a subnet holding the requested IP address; and forwarding the packet with the overlapping IP address with the virtual local area network tag to at least one local area network (LAN).