Message mapping for forced hold call handling in a vop environment

Abstract

If a communication client disconnects from a call, an interworking service node may receive from the communication client a disconnect message indicative of an attempt to disconnect the call and send a forced hold message to place the call on forced hold in response to receiving the disconnect message. A portion of the call extending toward a public service access point and through the PSTN is placed on hold. When an operator wants to reestablish the call to the communication client, the interworking service node will receive over the PSTN a reconnect request message to reestablish the call with the communication client. The reconnect request message may be an integrated services user part message. In response to the reconnect message, the interworking service node will generate and send a session initiation message, which is configured to reestablish the call toward the communication client.

1 . A method of maintaining a communication session, the communication session having a packet portion established over a packet network and a circuit switched portion established over a circuit switched network, the packet portion and the circuit switched portion being linked at a gateway, the method comprising:
 receiving at a service node an indication that the packet portion of the communication session may be inactive;   sending from the service node to the gateway a request to maintain the circuit switched portion of the communication session; and   initiating a session initiation message to re-establish the packet portion of the communication session.   
     
     
         2 . The method of  claim 1 , wherein the session initiation message is initiated at the service node. 
     
     
         3 . The method of  claim 1 , wherein the service node is integrated with the gateway and the session initiation message is initiated at the integrated service node and gateway. 
     
     
         4 . The method of  claim 1 , comprising sending over the circuit switched network an indication that the circuit switched portion of the communication session is to be maintained by the circuit switched network. 
     
     
         5 . The method of  claim 4 , wherein the sending over the circuit switched portion network an indication that the circuit switched portion of the communication session is to be maintained comprises sending an indication that the circuit switched portion is to be put on hold. 
     
     
         6 . The method of  claim 1 , wherein:
 the communication session is established between a packet communication device coupled to the packet network via a communication client and another communication device coupled to the packet network via the circuit switched network; and   the initiating the session initiation message comprises sending to the communication client of the packet communication device a request to re-establish the packet portion of the communication session.   
     
     
         7 . The method of  claim 1 , wherein the session initiation message is a Session Initiation Protocol (SIP) invite message. 
     
     
         8 . The method of  claim 1 , wherein the gateway couples a re-established packet portion of the communication session to a maintained circuit switched portion of the communication session. 
     
     
         9 . The method of  claim 6 , wherein the receiving at the service node an indication that the packet portion of the communication session may be inactive comprises receiving at the service node an indication that the packet communication device has gone on hook. 
     
     
         10 . The method of  claim 1 , wherein the sending from the service node to the gateway a request to maintain the circuit switched portion of the communication session comprises sending the gateway a request to put the circuit switched portion of the communication session on hold. 
     
     
         11 . The method of  claim 6 , wherein the initiating the session initiation message to re-establish the packet portion of the communication session comprises sending the Session Initiation Protocol (SIP) invite message from the service node to the communication client of the packet communication device. 
     
     
         12 . The method of  claim 1 , wherein the communication session is an emergency call. 
     
     
         13 . The method of  claim 6 , wherein the communication device comprises an emergency services communication device. 
     
     
         14 . The method of  claim 13 , wherein the emergency services communication device is coupled to the circuit switched network via an emergency services access point. 
     
     
         15 . The method of  claim 14 , wherein the emergency services access point is coupled to the circuit switched network via an emergency services switch. 
     
     
         16 . A method of maintaining a communication session, the communication session having a packet portion established over a packet network and a second portion established over a second network, the packet portion and the second portion being linked at a gateway coupled between the packet network and the second network, the method comprising:
 receiving at a service node an indication that the packet portion of the communication session may be inactive;   sending from the service node to the gateway a request to maintain the second portion of the communication session; and   initiating at the service node a session initiation message to re-establish the packet portion of the communication session.   
     
     
         17 . The method of  claim 16 , wherein:
 the communication session is established between a packet communication device coupled to the packet network via a communication client and a communication device coupled to the second network via the second network; and   the initiating at the service node a session initiation message comprises sending to the communication client a request to re-establish the packet portion of the communication session.   
     
     
         18 . The method of  claim 16 , wherein the session initiation message initiated by the service node is a Session Initiation Protocol (SIP) invite message. 
     
     
         19 . The method of  claim 16 , wherein the gateway couples the re-established packet portion of the communication session to the maintained second portion of the communication session. 
     
     
         20 . The method of  claim 17 , wherein the receiving at a service node an indication that the packet portion of the communication session may be inactive comprises receiving at the service node an indication that the packet communication device has gone on hook. 
     
     
         21 . The method of  claim 17 , wherein the initiating at the service node a session initiation message to re-establish the packet portion of the communication session comprises sending a Session Initiation Protocol (SIP) invite message from the service node to the communication client of the packet communication device. 
     
     
         22 . The method of  claim 16 , wherein the communication session is an emergency call. 
     
     
         23 . The method of  claim 17 , wherein the communication device coupled to the second network comprises an emergency services communication device.