Patent ID: 7711823

Claim:
An arrangement for establishing and maintaining a connection between communication devices via a data network, comprising: at least one server interfaced with the data network and data network terminals having network addresses, said server keeping a communication device register, a communication device and a terminal being arranged to establish a data transfer link between each other, wherein the communication device is arranged to report by sending via said data transfer link an identifier, as well as to send a call via said data transfer link, the terminal is arranged to send to the server the identifier received from the communication device and at the same time a network address of the terminal, and to notify the communication device about a call received from the server, the server has the communication device register for storing identifiers of reported communication devices and network addresses of terminals for the purpose of finding out reachability of the communication devices, the server is arranged to send network address of the terminal to another terminal in order to establish a network connection between the terminals, and the server is arranged to draw conclusions about relative locations of terminals for making the handover between the terminals during the connection between the communication devices, in which at least one communication device is a mobile terminal.