Media gateway and media gateway control unit

Abstract

A network interface unit (IM-MGW) in which signaling data is separated from useful data by the values of received data. The signaling data is tunneled to a control unit (MGCF). Two different data transmission networks (CS, IMS) can thus be simply combined, in particular, for video telephony.

1 . A media gateway, comprising:
 a receiver that receives, from a first data transmission network, payload data and H.245 signaling data, the H.245 signaling data and payload data being transmitted within the same bearer connection;   a signaling data transmission that sends the H.245 signaling data received at the receiver to a media gateway control unit, the H.245 signaling data being sent to the media gateway control unit unchanged and according to a control signaling method in accordance with the ITU-T H.248 protocol, the media gateway control unit controlling the media gateway and performing signaling interworking between the first data transmission network and a second data transmission network;   a payload data transmit unit that sends the payload data received at the receiver into the second data transmission network; and   a separation unit that separates the received H.245 signaling data and payload data from each other and forwards the H.245 signaling data to the signaling data transmit unit and forwards the payload data to the payload data transmit unit.   
     
     
         2 . The media gateway as claimed in  claim 1 , wherein the media gateway forwards the H.245 signaling data to the media gateway control unit via an external transmission link. 
     
     
         3 . The media gateway as claimed in  claim 1 , wherein the media gateway forwards a signaling message received from the media gateway control unit within an H.248-Notify message that contains as a parameter specifying that the signaling message is to be forwarded. 
     
     
         4 . The media gateway as claimed in  claim 1 , wherein the media gateway receives, from the media gateway control unit, an instruction to start H.223 negotiation to determine a multiplexing level for the bearer connection. 
     
     
         5 . The media gateway as claimed in  claim 1 , wherein media gateway, after negotiation of a multiplexing level, transfers to a media gateway control function a value of the multiplexing level in an H.248 Notify-Request message. 
     
     
         6 . A media gateway control unit for controlling a media gateway and for performing signaling interworking between a first data transmission network and a second data transmission network, comprising:
 a receiver that receives signaling data in accordance with a first signaling method for the first data transmission network, the signaling data being H.245 messages, wherein the signaling data is received from the first data transmission network via a bearer connection setup between the media gateway and the first data transmission network and wherein the H.245 messages from the first data transmission network are forwarded by the media gateway in unchanged form to the media gateway control unit via the ITU-T H.248 protocol;   a transmitter that transmits signaling data in accordance with a second signaling method for the second data transmission network; and   a conversion unit which, starting from a signaling message in accordance with the first signaling method, creates a corresponding signaling message in accordance with the second signaling method.   
     
     
         7 . The media gateway control unit as claimed in  claim 6 , wherein the media gateway control unit initiates the forwarding of H.245 signaling data performed by the media gateway. 
     
     
         8 . The media gateway control unit as claimed in  claim 7 , wherein the media gateway control unit initiates the forwarding by transmitting a message that contains a code for an H.248 event that specifies that forwarding is to be undertaken. 
     
     
         9 . The media gateway control unit as claimed in  claim 6 , wherein a media gateway control function transfers to the media gateway a H.245 signaling message as a parameter in a ITU-T H.248 Modify-Request message, the message containing a code that specifies that a message in accordance with the ITU-T H.248 protocol is being forwarded as a parameter. 
     
     
         10 . The media gateway control unit as claimed in  claim 6 , wherein the media gateway control unit causes the media gateway to begin negotiating a multiplexing level for the bearer connection by sending a message that contains an H.248 signal code that specifies that the negotiation of the multiplexing level is to begin. 
     
     
         11 . The media gateway control unit as claimed in  claim 10 , wherein a media gateway control function causes the media gateway to transmit a message to the media gateway control unit in which the value of a negotiated multiplexing level is specified, by sending a message containing an H.248 event code that specifies that the value of the multiplexing level is to be transmitted to the media gateway control function. 
     
     
         12 . The media gateway control unit as claimed in  claim 6 , wherein the media gateway control unit, when creating a TerminalCapabilitySet message in accordance with H.245 to be delivered to the media gateway, takes into account characteristics of the media gateway unit. 
     
     
         13 . The media gateway control unit as claimed in  claim 6 , wherein the media gateway control unit processes signaling data with signaling messages in accordance with a further signaling method for the first data transmission network, the signaling messages being transmitted in accordance with BICC or ISUP.