Patent ID: 8775673

Claim:
A method for routing a session initiation protocol (SIP) message in a communication network by a domain switch, comprising: registering a party with a first table of registered users of a first domain, the first domain having an associated first domain switch and the first table of registered users; receiving a SIP message directed to the party; parsing the message to determine a domain to which the party is registered; performing a table lookup using the first domain to retrieve a first destination code and a first Internet protocol (IP) address associated with the first domain switch; when the first destination code and the first IP address of the first domain switch are not retrieved, performing a table lookup to retrieve a third destination code and a third Internet protocol (IP) address of a super domain switch; when the first destination code and the first IP address of the first domain switch are retrieved, perform the following: embedding the first destination code into the message; routing the message to the first IP address of the first domain switch; determining that the party has roamed to a location associated with a second domain, the second domain having an associated second domain switch and a second table of registered users; updating the second table of registered users based on the determining; wrapping, by the first domain switch, the SIP message with a second destination code associated with the second domain switch; and routing the wrapped message to the second domain switch.