Abstract: A first network comprising: one or more first end-user computer terminals; a gateway to a second, packet-based network comprising one or more second end-user computer terminals installed with a communication client of the second network; one or more telephone units for performing calls with one of the second end-user computer terminals over the second network; wherein each of the one or more first end-user terminals is installed with a communication client for performing calls with the second end-user computer terminals over the second network; and wherein the gateway comprises switching apparatus configured to detect a user selection between a first state in which one of said calls is to be performed using one of said first end-user computer terminals and a second state in which the call is to be performed using one of said telephone units; and on condition of detecting the first state, to route both call set-up signaling and call media to the first end-user computer terminal; and on condition of detecting t

Abstract: A gateway, program and method for use in a packet-based communication system.

Abstract: Provided is a method of communicating using a user terminal that comprises: a first interface for exchanging call data with a first interface of a mobile communication device, wherein the mobile communication device comprises a second interface for interfacing with a node of a mobile telecommunications network, and wherein the first interface of the mobile communication device is unsuitable for interfacing with a node of a mobile telecommunications network; a second interface for exchanging call data with a second user terminal over a packet-based communication network; and a processor for executing a communications client, which processor is coupled to the first interface of the user terminal and to the second interface of the user terminal and is configured to participate in a call with the second user terminal via the second interface of the user terminal and the packet-based communication network; wherein the method comprises: sending call data via one of the first interface of the user terminal and the s

Abstract: A gateway, program and method for use in a packet-based communication system.

Abstract: A first network comprising: one or more first end-user computer terminals; a gateway to a second, packet-based network comprising one or more second end-user computer terminals installed with a communication client of the second network; one or more telephone units for performing calls with one of the second end-user computer terminals over the second network; wherein each of the one or more first end-user terminals is installed with a communication client for performing calls with the second end-user computer terminals over the second network; and wherein the gateway comprises switching apparatus configured to detect a user selection between a first state in which one of said calls is to be performed using one of said first end-user computer terminals and a second state in which the call is to be performed using one of said telephone units; and on condition of detecting the first state, to route both call set-up signalling and call media to the first end-user computer terminal; and on condition of detecting