RTSP PROXY EXTENDED TO DETECT STREAMING SESSION EVENTS AND REPORT TO VALUED STREAMING APPLICATIONS THE NOTIFIED ONES

摘要

An Extended RTSP Proxy interworks with an IP Application Server to offer valued multimedia streaming services to the subscribers. The Extended RTSP Proxy comprises a RTSP Proxy modified to further interface a Streaming Service Extension Module (SSEM). The Extended RTSP Proxy acts as intermediary between the client Requests and the relative Responses from one or more Video Servers. The SSEM module is responsible for monitoring the RTSP sessions originated by subscribers on the basis of instructions provided by the applications by proper Java APIs based on RMI (Remote Method Invocation) at the application interfaces. For this aim it deploys multiple instantiations of a state machine to detect event type session state change on behalf of each session addressed by a combination of a valid subscriber identifier and the identifier of the application invoked by the client. A personalized RTSP URL clickable on the Web is transferred inside the DESCRIBE and SETUP messages to provide the SSEM module with this information. Operatively, the SSEM module is piggyback the RTSP proxy to infer Event type Session State change from observations of the crossing signaling. The detected events are compared to registered notification lists of events transmitted by the Applications running inside the Application Server. In case of matching an event is reported back to the requesting application. The Extended RTSP Proxy uses TCP as reliable transport protocol for RTSP packets, and UDP to transport the RTP/RTCP streaming'data/control packets. Additional TCP ports are foreseen at the interface with the SSEM module. In a preferred embodiment valid for the IMS platform, the SSEM module can be located inside the Application Server. In such a case the personalized RTSP URL includes the SIP address of the client. When the applications are running inside Application Server outside the IMS domain, valid PLMN subscriber identifiers could be the MSISDN numbers of the subscriber .