Patent ID: 8165140

Claim:
A method, comprising: receiving a first internet protocol (IP) packet at a gateway connecting a first network to a second network, wherein the first packet is sent from a source in the first network, is directed to a destination in the second network, and includes source and destination port numbers; determining whether the first packet is an initiation request for a communication protocol, wherein the communication protocol specifies that, for the initiation request to succeed, the first packet include source and destination port numbers having a common, predetermined port number, and further specifies that the source and destination port numbers cannot be changed; determining whether any other initiation requests for the communication protocol are pending; in response to determining that the first packet is an initiation request for the communication protocol and to determining that no other initiation requests for the communication protocol are pending: forwarding the initiation request to the destination without changing the source and destination port numbers; and preventing initiation requests for the communication protocol from other sources from succeeding while the initiation request is pending.