Call routing using information in session initiation protocol messages

Abstract

A system and method for efficient and accurate establishment of SIP sessions between calling and called end-points. A calling endpoint creates a SIP INVITE request including a header portion and a body portion. The header portion includes standard routing information and the body portion includes additional information about the user and relevant to caller's intent. A SIP server receives a SIP INVITE request and determines an address of the called end-point as a function of the standard routing information contained in the header and the additional caller information contained in the body. The SIP server routes the session to the determined address.

What is claimed is:  
     
         1 . A method for establishing an IP telephony session between a first device and a second device, the method comprising: 
 receiving a call establishment message from the first device, the call establishment message including a first routing information in a header portion of the message and a second routing information in a body portion of the message;    determining an address of the second device based on the first and second routing information; and    using the address for routing the session to the second device.    
     
     
         2 . The method of  claim 1 , wherein the call establishment message is a session initiation protocol message.  
     
     
         3 . The method of  claim 1 , wherein the second routing information includes information gathered about a user of the first device.  
     
     
         4 . The method of  claim 1 , wherein the second routing information includes caller intent information.  
     
     
         5 . The method of  claim 4 , wherein the caller intent information includes information of an intent of a user of the first device in initiating the session.  
     
     
         6 . The method of  claim 1  further comprising writing new information in the first device for use in routing future IP telephony sessions initiated by the first device.  
     
     
         7 . A method for establishing an IP telephony session between a first device and a second device, the method comprising: 
 retrieving caller intent information from a data store on the first device;    creating a call establishment message including a header and a body, the body including the caller intent information; and    transmitting the caller initiation request to a server for routing the session to the second device based on the caller intent information.    
     
     
         8 . The method of  claim 7 , wherein the call establishment message is a session initiation protocol message.  
     
     
         9 . The method of  claim 7 , wherein the caller intent information includes information of an intent of a user of the first device in initiating the session.  
     
     
         10  The method of  claim 7  further comprising writing new caller intent information in the data store for use in routing future sessions initiated by the first device.  
     
     
         11 . An IP telephony system comprising: 
 a first device;    a second device; and    a server operative between the first device and the second device, characterized in that the first device creates a call establishment message including a header and a body, the body including caller intent information, the caller intent information being used by the server for determining an address of the second device for routing the session to the second device.    
     
     
         12 . The system of  claim 11 , wherein the call establishment message is a session initiation protocol message.  
     
     
         13 . The system of  claim 11 , wherein the caller intent information includes information of an intent of a user of the first device in initiating the session.  
     
     
         14 . The system of  claim 11  further characterized in that the server writes new information in the first device for use in routing future IP telephony sessions initiated by the first device.  
     
     
         15 . The system of  claim 11  further characterized in that the second device writes new information in the first device for use in routing future IP telephony sessions initiated by the first device.  
     
     
         16 . A server in an IP telephony system operative between a first device and a second device, the server being configured for: 
 receiving a call establishment message from the first device, the call establishment message including a first routing information in a header portion of the message and a second routing information in a body portion of the message;    determining an address of the second device based on the first and second routing information; and    using the address for routing the session to the second device.    
     
     
         17 . The server of  claim 16 , wherein the call establishment message is a session initiation protocol message.  
     
     
         18 . The server of  claim 16 , wherein the second routing information includes information gathered about a user of the first device.  
     
     
         19 . The server of  claim 16 , wherein the second routing information includes caller intent information.  
     
     
         20 . The server of  claim 19 , wherein the caller intent information includes information of an intent of a user of the first device in initiating the session.  
     
     
         21 . The server of  claim 16  further configured for writing new information in the first device for use in routing future IP telephony sessions initiated by the first device.