Patent ID: 8185109

Claim:
A telecommunications system comprising: a first telecommunications network with which a first telecommunications device is registered and having a radio access network; and a second telecommunications network with which a second telecommunications device is registered and operable to communicate with the second telecommunications device using the radio access network of the first telecommunications network; wherein the first telecommunications network includes a plurality of elements, each of which is operable to: perform a function; receive communications related to the second telecommunications device; wherein means are provided for generating a network identifier for indicating that the second telecommunications device is registered with the second telecommunications network, the generating means being operable to add the network identifier to communications related to the second telecommunications device transmitted to the plurality of elements of the first telecommunications network, the communications also including a user identifier for indentifying a user of the second telecommunication device; wherein each of the plurality of elements is operable to interpret the network identifier when received in one of the communications to determine whether the communication is from the first telecommunication device registered with first telecommunications network or from the second telecommunication device registered with the second telecommunications device and to adjust its operation based on the determination; wherein each of the plurality of elements is further operable to transmit a further communication derived from the communication to another one of the plurality of elements, the further communication also including the network identifier.