Session management method, apparatus and system

The invention relates to a session management method, a device and a system, wherein, the session management method implemented from the perspective of PCRF comprises the following steps of: receivingan AAR message of the current Rx session sent by the P-CSCF; associating the current Rx session with the Gx session associated with the previous Rx session based on the preset maintenance relationship and the AAR message. The preset maintenance relationship is the correspondence between the Gx session identifier of the Gx session and the user equipment address. The current Rx session is associated with the Gx session associated with the previous Rx session, which in turn enables a single Gx session to be associated with multiple Rx sessions, enabling session management for multi-party calls.The present application enhances the types of services supported by the IMS system, enabling the system to support rich VoLTE multi-party communication application scenarios. The present application provides an Rx session mana