Patent ID: 7277453
Filing Date: 2007-10-02
Classification: H04L

Abstract:
1. A method of communicating between IPv4 hosts in networks having private IPv4 address spaces, said method comprising the steps of: transmitting from a first private network one or more DNS queries for a remote IPv4 host in a second private network, said one or more DNS queries containing one or more resource record questions for said remote host name based on information from a requesting private IPv4 host in said first private network; receiving at said first private network one or more DNS replies from said second private network in response to said one or more DNS queries; detecting whether said one or more DNS replies comprises a private IPv4 address for said remote host in said second private network; effecting extracting if said one or more DNS replies comprise a synthesized IPv6 address, said effecting extracting in said first private network said IPv6 address for said remote host from said one or more DNS replies, said synthesized IPv6 address including a global IPv6 prefix and said private IPv4 address for said remote host, and allocating a peer IPv4 address in an address space of said first private network for said remote host, said peer IPv4 address associated with said extracted IPv6 address for said remote host; and addressing said remote host using said IPv6 address associated with said peer IPv4 address for transmission of IPv4 packets from said first private network addressed using said peer IPv4 address.