Inter-stream adaptation for collaborative multimedia applications

In new collaborative multimedia applications, there is a need for overall control, beyond the level of quality of service (QoS) as pertaining to individual streams in isolation of others. At every instant in time, the quality of the session, as perceived by the end user, depends on the priorities of the on-going streams, according to the application semantics, as well as on the actual QoS offered by the system to each of these streams. We introduce the concept of “Quality of Session” control. This is achieved by employing a monitoring mechanism for measuring the perceived QoS of each stream. In addition, in order to react to existing or potential bottlenecks in the network or end-systems, or skewness in the synchronization of views, an inter-stream adaptation mechanism is applied.