Abstract: A method of transporting image or video information between end user terminals via a packet switched network whilst a circuit switched connection is established between the end users includes establishing a circuit switched connection between a plurality of end user terminals for carrying voice traffic. The method also includes using the. Message Session Relay Protocol (MSRP) to encapsulate image or video information transmitted between end user terminals via a packet switched network, where MSRP related traffic is routed between said end user terminals via one or more MSRP enabled nodes. Additionally, the method includes installing service policies into the or at least one MSRP node from a session initiation protocol (SIP) application server (AS) located in the control-plane of an IMS network and checking multimedia service requests against the installed policies to control end user terminal access to certain packet based services.

Abstract: A method of transporting information between end user terminals via a packet switched network whilst a circuit switched connection is established between the end users, the method comprising: using the Message Session Relay Protocol, MSRP, to encapsulate information transmitted between users.

Abstract: According to the present invention there is provided a method of charging for a combinational multimedia service making use of circuit switched and packet switched services between participating user terminals and an IP Multimedia Subsystem, IMS, responsible for setting-up and controlling packet switched sessions, the method comprising: sending packet switched data generated by a first of the terminals, from a gateway node of a packet switched access network to the or each other terminal via a routing node having an IP address/port-number known a priori; and configuring a charging function associated with said gateway node to zero-rate data destined for said fixed IP address/port-number.