1. Mobicents Media Server

2. Endpoint/connection model Audio Video Rx/Tx Rx/Tx To endpoint's detectors From secondary sources From another connection (cnf mode) To another connection (cnf mode) To endpoint's generators To secondary sinks RTP/Local channel Video channel Source Sink DSP Source Sink DSP DSP

4. DSP algorithms Conference bridge, packet relay, media player/recorder Source Sink DSP Source Sink DSP DSP

6. Connection mode send only, receive only, send/receive, conference, loop, network loop Source Sink DSP Source Sink DSP DSP

8. Connection DTMF, Busy tone, VAD, ASR, TTS, Media player Source Sink DSP Source Sink DSP DSP

10. Filters AEC, Gain Control, etc Source Sink DSP Source Sink DSP DSP

12. Distributed DSP procedures

13. Clock skew problem Logic of Media server includes actions whose completions are time-constrained.

17. Latency unpredictable 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

19. EDF is an optimal scheduling algorithm on preemptive uniprocessors, in the following sense: if a collection of independent jobs, each characterized by an arrival time, an execution requirement, and a deadline, can be scheduled (by any algorithm) such that all the jobs complete by their deadlines, the EDF will schedule this collection of jobs such that they all complete by their deadlines.

20. EDF can guarantee that all deadlines are met provided that the total CPU utilization is not more than 100%. So, compared to fixed priority scheduling techniques like rate-monotonic scheduling, EDF can guarantee all the deadlines in the system at higher loading.

21. The feasibility test for periodic task sets:

23. Time slice: 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

24. Scheduler implementation Acceptor (Feasibility test) Priority Queue Executors(Threads) feadback

25. Exception In case of task sets with equal periods and task execution time less then time slice for RR both algorithms become First Comes First Serviced (FCFS) 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

27. Partitioning EDF task migration is not allowed

28. Utilization guarantee for EDF or any other static-priority multiprocessor scheduling algorithm – partitioned or global – cannot be higher than (m + 1)/2 for an m-processor platform

29. Determinism

30. Early Gap - Early Deadline First

31. Java Computitional benchmarks