Abstract: A negotiation unit for operation in a communication system whereby a first communication unit may transmit data to a second communication unit by means of a protocol including the step of negotiating a parameter for use in the operation of the protocol by the transmission of a first negotiation message to the second communication unit and in response thereto the transmission of a second negotiation message from the second communication unit to the first communication unit, the negotiation messages being configured to be capable of including data defining a value for the parameter, the negotiation unit comprising: storage means for storing information on a criterion on the parameter, interception means for intercepting at least one of the negotiation messages directed towards one of the first and second communication units; and message analysis means for analysing the intercepted negotiation message and if the message includes a value for the parameter f) checking whether the stored criterion on the value is m

Abstract: A negotiation unit for operation in a communication system whereby a first communication unit may transmit data to a second communication unit by means of a protocol including the step of negotiating a parameter for use in the operation of the protocol by the transmission of a first negotiation message to the second communication unit and in response thereto the transmission of a second negotiation message from the second communication unit to the first communication unit, the negotiation messages being configured to be capable of including data defining a value for the parameter, the negotiation unit comprising: storage means for storing information on a criterion on the parameter, interception means for intercepting at least one of the negotiation messages directed towards one of the first and second communication units; and message analysis means for analysing the intercepted negotiation message and if the message includes a value for the parameter f) checking whether the stored criterion on the value is m

Abstract: A method and apparatus for permitting mobile communications between a Mobile Services Switching Center (MSC) and a Mobile Station (MS) and between MSs by establishing for each transaction, including a call, an Internet Protocol (IP) connection in an IP network. In the invention a call to a MS is initiated by sending from the MSC to the MS, via the IP network, a call initiation message causing the MS to send a response message which includes a mobile identity that can be used as a session identifier identifying the MS. Responsive to the response message, the MSC sends a call set up message to establish an IP connection in the IP network upon which a transaction including the call is to be conducted. The call set up message includes a transaction ID which identifies the transaction. The IP network stores the transaction ID and maps the transaction ID with respect to the session identifier and the IP connection to be established.