Patent ID: 7945241

Claim:
A communication network, comprising: a visited IMS network adapted to provide service for a roaming user, the visited IMS network comprising: a visited charging data system; and a visited network element adapted to receive a first signaling message for a session from the roaming user, to assign a visited charging identifier for the session, to insert the visited charging identifier in the first signaling message, and to transmit the first signaling message to a home IMS network for the roaming user; the visited network element further adapted to receive a second signaling message for the session from a home network element in the home IMS network, to process the second signaling message to identify a home charging identifier assigned to the session in the home IMS network and to identify additional home network charging information for the session, to generate a visited charging message for the session, to insert the home charging identifier, the visited charging identifier, and the additional home network charging information in the visited charging message, and to transmit the visited charging message to the visited charging data system; the visited charging data system is adapted to receive the visited charging message from the visited network element, to process the visited charging message to identify the home charging identifier, the visited charging identifier, and the additional home network charging information for the session, to generate a visited Charging Data Record (CDR) for the session, to insert the home charging identifier, the visited charging identifier, and the additional home network charging information in the visited CDR, and to transmit the visited CDR to a visited billing system.