NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O...

55
1 NUS.SOC.CS5248 Ooi Wei Tsang CPU Scheduling

TAGS:

Transcript of NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O...

Page 1: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

1

NUS.SOC.CS5248Ooi Wei Tsang

CPU Scheduling

Page 2: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

2

Scheduling Task vs I/O RequestTask computation time

unpredictable

Task can be preemptive

Page 3: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

3

CPU Scheduling Algorithm

FCFSPriority-basedProportional fair-shareEDFRate monotonic

Page 4: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

4

Rate Monotonic

Page 5: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

5

EDF

Page 6: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

6

Problem

How can multimedia applications co-exists with normal applications?

Page 7: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

7

Same Idea as Cello

P. Goyal, X. Guo, and H. M. Vin.

“A hierarchical CPU scheduler formultimedia operating systems.”

OSDI’96

Page 8: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

8

Guarantee?

So far: Best-Effort Real-Time Scheduling

What about: Guaranteed service?

Page 9: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

9

How to Guarantee Services?

Page 10: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

10

NUS.SOC.CS5248Ooi Wei Tsang

Resource Reservation: CPU

Page 11: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

11

Resource Reservations

How to reserve?Overbook?Overuse?

Page 12: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

12

Example: Memory

How to reserve?malloc

Overbook? return NULL

Overuse? crash, throw exception

Page 13: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

13

Example: CPU

How to reserve?Overbook?Overuse?

Memory is discrete. CPU time is continuous.

Page 14: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

14

NUS.SOC.CS5248Ooi Wei Tsang

How to Reserve?

Page 15: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

15

CPU Reservation

“I need C units of time .. out of every T units.”

Page 16: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

16

Some Issues

“I need C units of time, out of every T units.”

Page 17: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

17

Effects of T and C

Page 18: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

18

Effects of T and C

0%10%20%30%40%50%60%70%80%90%

100%

0 10 20 30 40 50 60Reservation Period (ms)

% F

ram

es

Re

ndere

d

20% 15% 10%

Page 19: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

19

Schedulability Theorems

Rate Monotonic Scheduler

Earliest Deadline First

Page 20: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

20

Assumptions

programs are periodiccomputation time is constant zero context switch timeprograms are independent

Page 21: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

21

NUS.SOC.CS5248Ooi Wei Tsang

Rialto SchedulerCPU Reservations and Time Contraints: Efficient and Predictable Scheduling of Independent Activities,M. Jones, D. Rosu and M. Rosu

Page 22: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

22

Why Rialto?

Provide CPU reservationEnable deadlinesCo-exists with best-effort apps

Page 23: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

23

Overview

input: a set of tasks and their reservation

pre-compute a scheduling graph

schedule tasks based on scheduling graph

Page 24: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

Task A B C D E F

Amount C 4 3 2 1 1 5

Period T 20 10 40 20 10 40

EB CA

EB FD

EB A

EB D

Page 25: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

Task A B C D E F

Amount

4 3 2 1 1 5

Period 20 10 40 20 10 40

C

F

A

D

EB

Page 26: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

26

Advantages

Only need to make new scheduling decisions when new task is added

Page 27: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

27

Computing Scheduling Graph Input: A set of tasks with their

reservationsOutput: A scheduling graph if

feasible

Page 28: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

28

Many Possible Solutions

C

F

A

D

EBF

C

A

D

EB

Page 29: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

Task A B C D E F

Amount

4 3 2 1 1 5

Period 20 10 40 20 10 40

C

F

F

A

D

EB

Page 30: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

30

Computing Scheduling Graph

Input: A set of tasks with their reservations

Output: A scheduling graph if feasible

Goals: (a) Minimize context switches (b) Distribute free time evenly

Page 31: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

31

Life is Tough..

NP-Hard

Page 32: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

32

Heuristic

10

10

10

10

10

10

10

Page 33: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

10

5

10

10

5

10

5

F

Task A B C D E F

Amount

4 3 2 1 1 5

Period 20 10 40 20 10 40

Page 34: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

6

1

6

6

1

6

1

F

B+E

Task A B C D E F

Amount

4 3 2 1 1 5

Period 20 10 40 20 10 40

Page 35: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

4

1

1

1

1

1

1

F

B+E

A+D

C

Task A B C D E F

Amount

4 3 2 1 1 5

Period 20 10 40 20 10 40

Page 36: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

36

Time Constraint

“I need to run the following code, that takes 30ms, 100ms from now, and the deadline is (now+180ms).”

Page 37: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

37

Pseudocode

can = begin_constraint(start_time, deadline, estimate)

if can schedule thendo work

elseadapt

time_taken = end_constraint()

Page 38: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

38

Scheduling Constraints

C

F

F

A

D

EB

Page 39: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

39

Advantages

Only need to make new scheduling decisions when new task is added

Feasibility of time constraint can be predicted accurately

Page 40: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

40

Running Unreserved Task

C

F

F

A

D

EB

Page 41: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

41

NUS.SOC.CS5248Ooi Wei Tsang

Media Player on Rialto/NT

Page 42: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

42

Look inside NT Scheduler

Scheduling unit : ThreadPriority level: 1-15, 16-31

rt 24 high 13 normal 8 idle 4

Page 43: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

43

Priority Boosting

Example: Priority +6 after awaken by

keyboard input

Page 44: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

44

Anti-Starvation

If hasn’t run for 3 seconds Boost priority to 14

Avoid “Priority Inversion”

Page 45: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

45

Mars Pathfinder

Page 46: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

46

Rialto/NT

NT Scheduler

RialtoC

F

F

A

D

EB

Boost Priorityto 30

Page 47: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

47

Win Media Player 6.4

Period Priority Thread

10 24 Kernel Mixer

45 8 GUI

100 15 Timer

100 9 MP3 Decoder

500 8 Unknown

2000 8 Disk Reader

Page 48: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

48

Experiment 1

WMP running alone

Period Priority Thread

10 24 Kernel Mixer

45 8 GUI

100 15 Timer

100 9 MP3 Decoder

500 8 Unknown

2000 8 Disk Reader

Page 49: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

49

Experiment 2

WMP running with priority 8 competitor

Period Priority Thread

10 24 Kernel Mixer

45 8 GUI

100 15 Timer

100 9 MP3 Decoder

500 8 Unknown

2000 8 Disk Reader

Page 50: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

50

Experiment 3

WMP running with priority 10 competitor

Period Priority Thread

10 24 Kernel Mixer

45 8 GUI

100 15 Timer

100 9 MP3 Decoder

500 8 Unknown

2000 8 Disk Reader

Page 51: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

51

Experiment 5

WMP running with priority 10 competitor

Period Priority Reservation Thread

10 24 Kernel Mixer

45 8 GUI

100 15 Timer

100 9 40/1024 MP3 Decoder

500 8 Unknown

2000 8 Disk Reader

Page 52: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

52

Experiment 6

WMP running with priority 10 competitor

Period Priority Reservation Thread

10 24 1/16 Kernel Mixer

45 8 GUI

100 15 Timer

100 9 40/1024 MP3 Decoder

500 8 Unknown

2000 8 Disk Reader

Page 53: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

53

Experiment 7

WMP running with priority 10 competitor

Period Priority Reservation Thread

10 24 Kernel Mixer

45 8 GUI

100 15 Timer

100 9 20/512 MP3 Decoder

500 8 Unknown

2000 8 Disk Reader

Page 54: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

54

NUS.SOC.CS5248Ooi Wei Tsang

Summary

Page 55: NUS.SOC.CS5248 Ooi Wei Tsang 1 CPU Scheduling. NUS.SOC.CS5248 Ooi Wei Tsang 2 Scheduling Task vs I/O Request Task computation time unpredictable Task.

NUS.SOC.CS5248Ooi Wei Tsang

55

CPU Scheduling

With guarantee percentage of CPU time task with deadline

Algorithms Rate-monotonic EDF Rialto


Tsang SCADA Attacks

Tsang SCADA Attacks

OOI-CI & IOOS-DMAC Intersection Project FY2010. OOI Overview.

OOI-CI & IOOS-DMAC Intersection Project FY2010. OOI Overview.

Nus.soc.cs5248 Ooi Wei Tsang 1 Intermedia Synchronization Ooi Wei Tsang.

Nus.soc.cs5248 Ooi Wei Tsang 1 Intermedia Synchronization Ooi Wei Tsang.

1 Multimedia Storage Issues. NUS.SOC.CS5248 OOI WEI TSANG 2 Media vs. Documents large file size write once, read many deadlines!

1 Multimedia Storage Issues. NUS.SOC.CS5248 OOI WEI TSANG 2 Media vs. Documents large file size write once, read many deadlines!

NUS.SOC.CS5248-2010 Roger Zimmermann (based on slides by Ooi Wei Tsang) Systems Support for Continuous Media.

NUS.SOC.CS5248-2010 Roger Zimmermann (based on slides by Ooi Wei Tsang) Systems Support for Continuous Media.

NUS.SOC.CS5248 Ooi Wei Tsang Application-Level Multicast.

NUS.SOC.CS5248 Ooi Wei Tsang Application-Level Multicast.

NUS.SOC.CS5248 Ooi Wei Tsang Rate Adaptations. NUS.SOC.CS5248 Ooi Wei Tsang You are Here Network Encoder Sender Middlebox Receiver Decoder.

NUS.SOC.CS5248 Ooi Wei Tsang Rate Adaptations. NUS.SOC.CS5248 Ooi Wei Tsang You are Here Network Encoder Sender Middlebox Receiver Decoder.

Dali Virtual Machine Wei Tsang Ooi (With Brian, Sugata, Tibor, Steve, Haye, Matthew, Dmitriy)

Dali Virtual Machine Wei Tsang Ooi (With Brian, Sugata, Tibor, Steve, Haye, Matthew, Dmitriy)

NUS.SOC.CS5248 Ooi Wei Tsang 1 CS6282 Very Large Scale Distributed Systems Ooi Wei Tsang SOC1-04-20 ooiwt@comp.nus.edu.sg.

NUS.SOC.CS5248 Ooi Wei Tsang 1 CS6282 Very Large Scale Distributed Systems Ooi Wei Tsang SOC1-04-20 [email protected].

NUS.SOC.CS5248-2007 Roger Zimmermann (based on slides by Ooi Wei Tsang) MPEG + RTP.

NUS.SOC.CS5248-2007 Roger Zimmermann (based on slides by Ooi Wei Tsang) MPEG + RTP.

NUS.SOC.CS5248-2007 Roger Zimmermann (based on slides by Ooi Wei Tsang) Media Compression.

NUS.SOC.CS5248-2007 Roger Zimmermann (based on slides by Ooi Wei Tsang) Media Compression.

NUS.SOC.CS5248 Ooi Wei Tsang MPEG + RTP. NUS.SOC.CS5248 Ooi Wei Tsang Previously, on CS5248 MPEG Compression Sequence, GOP, Picture, Slice, Macroblock,

NUS.SOC.CS5248 Ooi Wei Tsang MPEG + RTP. NUS.SOC.CS5248 Ooi Wei Tsang Previously, on CS5248 MPEG Compression Sequence, GOP, Picture, Slice, Macroblock,

Wireless Multicast for Zoomable Video Streaming · Wireless Multicast for Zoomable Video Streaming Hui Wang, Mun Choon Chan and Wei Tsang Ooi School of Computing, National University

Wireless Multicast for Zoomable Video Streaming · Wireless Multicast for Zoomable Video Streaming Hui Wang, Mun Choon Chan and Wei Tsang Ooi School of Computing, National University

NUS.SOC.CS5248-2015 Roger Zimmermann (based in part on slides by Ooi Wei Tsang) Protocols.

NUS.SOC.CS5248-2015 Roger Zimmermann (based in part on slides by Ooi Wei Tsang) Protocols.

OOI Program Update

OOI Program Update

NUS.SOC.CS5248 Ooi Wei Tsang Systems Support for Continuous Media OOI WEI TSANG.

NUS.SOC.CS5248 Ooi Wei Tsang Systems Support for Continuous Media OOI WEI TSANG.

NUS.SOC.CS5248-2015 Roger Zimmermann (based on slides by Ooi Wei Tsang) Systems Support for Continuous Media.

NUS.SOC.CS5248-2015 Roger Zimmermann (based on slides by Ooi Wei Tsang) Systems Support for Continuous Media.

NUS.SOC.CS5248-2011 Roger Zimmermann Project Packetize MP3 audio into RTP Packets.

NUS.SOC.CS5248-2011 Roger Zimmermann Project Packetize MP3 audio into RTP Packets.

NUS.SOC.CS2105 Ooi Wei Tsang Application Transport Network Link Physical you are here.

NUS.SOC.CS2105 Ooi Wei Tsang Application Transport Network Link Physical you are here.

1 Course Matters. NUS.SOC.CS5248 OOI WEI TSANG 2 Paper Review October 2003 MonTueWedThuFriSatSun 171819 20212223242526 Paper Reviews Due 20% off for each.

1 Course Matters. NUS.SOC.CS5248 OOI WEI TSANG 2 Paper Review October 2003 MonTueWedThuFriSatSun 171819 20212223242526 Paper Reviews Due 20% off for each.