Abstract: A wireless telecommunications system comprises a radio network layer for carrying mobile-specific signaling, and a transport layer for establishing user channels between system nodes over a transport network. The transport network is visible to the radio network layer only via a primitive interface through which it can request transport services. The invisibility of the transport network to the radio network layer makes the radio network layer independent of the underlying transport network and enables the use of different transport network technologies. The radio network layer signaling procedures and connections are mapped with the underlying transport layer signaling procedures and connections by using binding information at one end of the connection leg, which is exchanged between the network and transport layers through a primitive interface, and used to “identify” the radio network layer and the transport layer connection setup signaling carried out between the nodes.