| 摘要 |
<p>Embodiments disclosed herein provide a method of Completion of Calls to Busy Subscriber (CCBS) screening for a blacklisted IP multimedia subsystem (IMS) network, the method comprising steps of a calling party making a call to a called party, where the calling party and the called party belong to different IMS networks; the called party transmitting a 486 Busy Here message to IMS network of the called party, when the called party is busy; and IMS network of the called party checking for IMS network of the calling party in a list of non-blacklisted IMS networks. The IMS network of the called party blocks header Allow-Events:ccbs in the 486 Busy Here message to the calling party network, on failing to detect the calling party in the list of non-blacklisted IMS networks.</p> |
