Patent ID: 7965690

Claim:
A telecommunications system comprising: a mobile network having a plurality of portable communication devices, and router means arranged in use for routing data to and from the portable communication devices; and a main network which includes a signalling agent, a plurality of directory agents, and a plurality of spaced apart attachment points to which the mobile network can attach in order to communicate with the main network, wherein, in use, each directory agent stores routing information for routing data to a respective portable communication device associated with that directory agent, and wherein, the signalling agent, in use, maintains a register of directory agents currently associated with the mobile network, the signalling agent being updated as portable communication devices attach to, and detach from, the mobile network, and wherein in response to a signalling message from which it is inferred that the point of attachment of the mobile network has changed, the signalling agent is configured to generate using the register respective update messages for each directory agent currently associated with the signalling agent for transmission to the respective directory agents, the update messages each including updated routing information such that on receipt of the updated routing information, each directory agent updates the stored routing information thereof so as to take into account the changed point of attachment of the mobile network.