Patent ID: 7313145

Claim:
A method of establishing a path between end points in a communications network, said communications network comprising a private network connected to a packet data network the method comprising the steps of: a) identifying a first end point and a second end point from a communications session set up request initiated by the first end point, at least one of said end points being located in the private network; b) identifying for said first end point a network address translation (NAT) function associated with said first end point; c) identifying for said second end point a NAT function associated with said second end point; d) comparing the NAT functions identified for said first and second end points; and e) where the comparison of said NAT functions reveals that said functions include a same NAT function, establishing a packet data transmission path between said end points by instructing said first end point to use a private network address of said second endpoint and instructing said second endpoint to use a private network address of said first endpoint, said private network addresses of said first and second endpoints comprising a private network address space for said private network, said private network address space being different to an address space of the packet data network, whereby said packet data transmission path does not utilise said same NAT function for packet transmission.