Patent ID: 7639668

Claim:
A method for a call server to support a media session between a local endpoint and a remote endpoint, the local endpoint belonging to a local network that includes a middlebox which comprises a NAT, the method comprising: a) in a signaling session, receiving a message from the local endpoint or the remote endpoint, wherein the message requests to establish a connection for the media session and contains local and remote address information for the requested media session, and the local address information comprises private address information; b) forwarding the local and remote address information to the middlebox so that the middlebox will be able to identify packets associated with the media session from at least said information and will thereby be able to appropriately process said packets; c) receiving a mapping from the NAT which relates the private address information to public address information for the local endpoint; d) forwarding the mapping to the local endpoint; e) receiving a revised version of the message from the local endpoint, wherein the public address information has been substituted for the private address information; and f) forwarding the revised version of the message to a host computer associated with, respectively, the remote endpoint or the local endpoint.