Telecommunications system which includes two networks

The mobile network where the present invention has a telecommunication system and especially two or more portable communication apparatus, It is related with a telecommunication system including a fixed network including a signaling agent, two or more directory agents, and the estranged connection point of the plurality which can connect this mobile network. Each directory agent memorizes during use the routing table for sending data to each mobile communications equipment related with the directory agent. If this connection point of this mobile network changes, this mobile network will transmit an address modification message to this signaling agent. Routing table can be updated in order that each may, as a result, take into consideration the connection point where this mobile network was this changed, since it is constituted so that this signaling agent may transmit change of this address to each directory agent according to it. Since this signaling agent is offered, in itself each portable equipment to the directory agent, It is not necessary to report when this mobile network moves, and the quantity of signaling between this mobile network and this fixed network in case this mobile network moves is reduced. [Selection figure] Fig. 1