Method and system for proxying telephony messages

Abstract

A proxy computer of a network can receive incoming telephony messages from one or more computers outside of the network and proxy them to computers within the network. Similarly, the proxy computer can receive outgoing telephony messages from within the network and proxy them to computers outside of the network. To set up inbound calls, a proxy program on the proxy computer looks for the presence of an alias in the call signaling messages, references a data structure to determine which computer on the network is associated with the alias, and proxies the call signaling and control messages between the callee computer and the calling computer based on the association, thereby creating a logical connection between the calling computer and the callee computer.

1 . (canceled) 
   
   
       2 . A method of proxying telephony messages, the method comprising:
 associating an internet protocol (IP) address of a proxy computer with an alias;   registering the alias with a directory service, wherein the alias corresponds to a callee computer;   initiating a request to the callee computer using the alias;   submitting the request to the directory service; and   matching the alias in a directory and returning the IP address that is listed for the alias, which is the public network address of the proxy computer.   
   
   
       3 . The method of  claim 2 , wherein a calling computer initiates the request to the callee computer using the alias. 
   
   
       4 . The method of  claim 2 , wherein the alias of the callee computer is used to request the IP address of the proxy computer. 
   
   
       5 . The method of  claim 2 , further comprising:
 receiving a first call control message from a calling computer of a public network;   generating a second call control message; and   sending the second call control message to the callee computer.   
   
   
       6 . The method of  claim 5 , wherein the first call control message comprises the public network address of the proxy computer and a first set of port assignments for media communication between the proxy computer and the calling computer on behalf of the callee computer. 
   
   
       7 . The method of  claim 6 , wherein the first set of port assignments are assigned by the calling computer. 
   
   
       8 . The method of  claim 7 , wherein the first set of port assignments includes a port for audio transmissions and another port for video transmissions between the proxy computer and the calling computer on the behalf of the callee computer. 
   
   
       9 . The method of  claim 6 , wherein the second call control message comprises a private network address of the callee computer and a second set of port assignments for media communication between the proxy computer and the callee computer on behalf of the calling computer. 
   
   
       10 . The method of  claim 9 , where the second set of port assignments are assigned by the proxy computer. 
   
   
       11 . The method of  claim 10 , wherein the second set of port assignments includes a port for audio transmissions and another port for video transmissions between the proxy computer and the callee computer on the behalf of the calling computer. 
   
   
       12 . The method of  claim 11 , wherein the calling computer exchanges data with the private network computer via the proxy computer using the first set of ports assigned by the calling computer, and the proxy computer forwards the data to the private network computer using the second set of ports assigned by the proxy computer. 
   
   
       13 . The method of  claim 5 , wherein the proxy computer sends the second call control message to the callee computer on behalf of the calling computer. 
   
   
       14 . The method of  claim 5 , wherein the first and second call control messages are open logical channel messages for opening logical channels between the calling computer and the proxy computer and between the callee computer and the proxy computer, respectively. 
   
   
       15 . The method of  claim 14 , wherein the open logical channel messages are structured in accordance with the H.245 protocol. 
   
   
       16 . A method of registering with a directory service, the method comprising:
 receiving a message comprising an alias for identifying a callee computer;   registering the alias corresponding to the callee computer with the directory service; and   associating an internet protocol (IP) address of a proxy computer with the alias.   
   
   
       17 . The method of  claim 16 , further comprising creating an entry for the alias associated with the IP address of the proxy computer. 
   
   
       18 . The method of  claim 16 , wherein the alias is an email alias. 
   
   
       19 . A system for facilitating the proxying of telephony messages, the system comprising:
 means for associating an internet protocol (IP) address of a proxy computer with an alias;   means for registering the alias with a directory service, wherein the alias corresponds to a callee computer;   means for initiating a request to the callee computer using the alias;   means for submitting the request to the directory service;   means for matching the alias in a directory and returning the IP address that is listed for the alias, which is the public network address of the proxy computer;   means for receiving a first call control message from a calling computer of a public network;   means for generating a second call control message; and   means for sending the second call control message to the callee computer.   
   
   
       20 . The system of  claim 19 , wherein the first call control message comprises the public network address of the proxy computer and a first set of port assignments for media communication between the proxy computer and the calling computer on behalf of the callee computer. 
   
   
       21 . The system of  claim 20 , wherein the second call control message comprises a private network address of the callee computer and a second set of port assignments for media communication between the proxy computer and the callee computer on behalf of the calling computer.