Patent ID: 7512136

Claim:
A method for preserving Internet Protocol (IP) addresses, comprising: communicating routing data to a first gateway to form a routing table through the Internet; generating an Address Resolution Protocol (ARP) proxy table from the routing table at the first gateway; receiving at the first gateway coupled to a first local network an Address Resolution Protocol request from a first host also coupled to said first local network, where said ARP request includes a destination IP address of a second host coupled to a second gateway and a second local network, said first gateway and the second gateway in communication through the Internet, and where a source IP address of said first host and said destination IP address are within a common IP address sub-network; sending a local network address of said first gateway to said first host in reply to said ARP request, based on an entry for said destination IP address in the ARP proxy table stored on said first gateway; directing a packet from said first host using the local network address, addressed to said second host, where said packet includes said source IP address and said destination IP address; and transmitting said packet toward said second host from the first gateway through the Internet and the second gateway.