Charging for roaming users in ims networks

Public a method for between belonging to the IMS network (110) and visits IMS network (120) is common information and a communication network (100) and method. A in the visiting IMS network (120) for session's signalling message, and visits IMS network (120) distribution visiting charging identifier, such and ICID, and a belonging to the IMS network (110) share the visiting charging identifier connected with the signalling message. Similar, belonging to the IMS network (110) distribution ownership identifier cost, and a visiting the IMS network (120) share the ownership charging identifier connected with the signalling message. The belonging to the IMS network (110) and visits IMS network (120) of CDR, and a network belong to the charging identifier and visiting charging identifier comprises a CDR, so of a bill system (116,126) can be easily with different from IMS network (110,120) CDR.