Patent ID: 7486668

Claim:
A method comprising: (a) inserting a first signaling message element into a first signaling message, the inserting being performed by a first network node; (b) receiving the first signaling message and the first signaling message element onto a second network node from the first network node, the first signaling message being received via a transmission link that connects the second network node with the first network node, the first signaling message element requesting the transmission of a first identification parameter that identifies the second network node; (c) using the first signaling message to control a connection setup of a data transmission between a first terminal and a second terminal, the first terminal and the second terminal and the first network node and the second network node being parts of a first data transmission network; (d) transmitting a second signaling message from the second network node back through the transmission link to the first network node, the second signaling message containing the first identification parameter, wherein the first identification parameter is an internal line number that is used to request identification parameters from the second network node; (e) generating a third signaling message using the internal line number, the generating being performed by the first network node; (f) receiving the third signaling message and a third signaling message element onto the second network node from the first network node, the third signaling message element requesting the transmission of a second identification parameter that identifies the second network node; and (g) transmitting a fourth signaling message from the second network node back through the transmission link to the first network node, the fourth signaling message containing the second identification parameter.