A communication system supporting communication of packet data. It comprises a core network, which includes a number of packet data support nodes, a number of gateway nodes for communication with external packet data networks, and a number of radio networks. Each radio network includes radio network control means. At least some of the packet data support nodes include a separate functional server node. A number of the functional server nodes are provided to control at least a number of radio network control means such that the functional server nodes are able to control any radio network control means.