A characterization method for a network address translation (NAT) device by an internal computer behind the NAT device includes creating a plurality of sockets; binding the plurality of sockets, respectively, to a plurality of ports; transmitting a plurality of STUN requests in user datagram protocol...http://www.google.se/patents/US7957406?utm_source=gb-gplus-sharePatent US7957406 - Method and apparatus for packet traversal of a network address translation device
