Distributed network address translation for a network telephony system

A method for distributed network address translation on a network telephony system, comprising in combination:

• requesting at a first network phone with a first protocol, at least one locally unique port from a first network device, wherein the first network phone and the first network device are located on a first network;
• receiving at the first network phone with the first protocol, the at least one locally unique port from the first network device;
• creating a request in a higher level protocol layer in a layered protocol stack on the first network phone, for a second network device on a second network, wherein the request includes a common external network address and a local port on the first network phone;
• forwarding the request from the higher level protocol layer to a lower level protocol layer in the first network phone;
• translating the local port in the request to a locally unique port in the lower level protocol layer on the first network phone;
• sending the request from the first network phone to a third network device on the first network;
• and
• forwarding the request from the third network device to the second network device.

A method for distributed network address translation in a network telephony system, comprising in combination:

• registering a proxy server with a router to register a specified port to the proxy server, wherein the proxy server and the router are located on a first network having at least one common external network address, and wherein the proxy server is operable to access at least one network address corresponding to at least one network phone on the first network;
• receiving at the proxy server at least one request from an external network phone located on an external network, wherein the request includes the at least one common external network address and the specified port;
• and
• proxying the at least one request to the at least one network phone on the first network.

A method for distributed network address translation in a network telephony system, comprising in combination:

• obtaining at least one locally unique port respectively for at least one network phone on a first network, wherein at least one common external network address is associated with the first network;
• registering the at least one network phone with a registration server;
• receiving at a redirect server at least one request from an external network phone located on an external network, wherein the redirect server is registered to a specified port, wherein the request includes the at least one common external network address and the specified port;
• and
• sending a redirect message from the redirect server to the external network phone.