ON-DEMAND MULTI-CHANNEL STREAMING SESSION OVER PACKET-SWITCHED NETWORKS

摘要

The invention provides a solution for switching between channels belonging to one on- demand multi-channel streaming session. An aggregation procedure for aggregating of a number of session descriptions parameters corresponding to a multitude of channels into one single session description is proposed. Further each channel is described by a mandatory unique identifier, which can be referenced in a channel switch request and an optional human readable identifier for display in a title bar or a channel selection menu. A corresponding client application processes the SDP describing the channel bundle and uses the found information for allowing a user to switch to a channel associated with a certain identifier. Signaling of a channel switch request is done preferably via an RTSP SET_PARAMETR message or as an alternative out-band via HTTP. A channel switch control unit, which is part of the multi-channel streaming server, receives a multitude of RTP flows and selects one of the flows for forwarding to the client. A switching point determination is a part of the channel switch control unit and determines the next possible point of time for switching to a requested channel. The client application receives time information for the switch point in response to a channel switch request.