A method for initiating a session within a publish/subscribe network, comprises: publishing a first topic by a first user interface of a first device, the topic identifying the first user interface and including an address-identifier identifying a second user interface of another device, triggering a request to start a session, starting a first media endpoint (43, 44) by publishing the media endpoint to the network by using a second topic for the media end point representing the media end point and describing the capabilities of the media endpoint, and linking the first media endpoint with a second media endpoint (45, 46) of the second user interface (42), when the second user interface has accepted the session.