Distributed Multimedia Systems Resource management and Stream Adaptation Arun A Tharuvai CSC8530 October 21, 2003

Topics Summary of Distributed Multimedia Systems Resource Management Stream Adaptation

Introduction hmm

Characteristics of multimedia Continuous Isochronous (time-based) Bandwidth intensive Compressible

Quality of Service (QoS) Management Management and allocation of resources to guarantee service QoS Manager negotiates requirements with applications against existing resources

Resource Management Management of Resources to provide minimal QoS level to application Resource Scheduling Fair Scheduling Real time Scheduling

Resource Scheduling Priority determination techniques Responsiveness Fairness Deadline handling

Fair scheduling Round-robin queuing either by packet or by bit to prevent bandwidth clogging Equal bandwidth is assigned to each stream Weighted fair queuing is a variant

Real-time Scheduling Assign CPU time slots to processes, ensuring tasks EDF – Earliest Deadline First RM – Rate monotonic QoS can’t be guaranteed

Stream Adaptation Applications adjust performance Scaling Filtering

Scaling Adapt stream to the bandwidth available at source Subsample stream

Scaling (II) Temporal scaling Spatial scaling Frequency scaling Amplitudinal scaling Color space scaling

Filtering Applies scaling at nodes between source and destination Streams are partitioned into hierarchical quality dependent substreams. Dropped when node capacity is full

Conclusion Two techniques for ensuring that multimedia systems transfer from source to destinations Resource management Stream Adaptation