Video streaming, video server, live streaming, video on demand

1. Master Thesis Presentation
Waqas Daar
(daar@kth.se)
School of Information and Communication Technology
Royal Institute of Technology (KTH)
Stockholm, Sweden
Examiner : Markus Haidel
Supervisor: Renato Lo Cigno
University of Trento, Italy
Date: May 17, 2010 Opponent : Waqas Warraich

2. Outline
 Motivation
 Background
 Video streaming
 Challenges for streaming
 Streaming protocols
 Study of video server architecture
 Distribution Agnostic Video Server (DAVS) design
 Testing of DAVS
 Conclusion and future work
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4. Motivation
 New multimedia streaming applications are not immune to
interaction with the current Internet and client server
model.
 To compare distinct streaming technologies.
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5. Problem statement
 A video server which can be dynamically coupled to
different streaming and distribution techniques,
making the service independent, or agnostic, to the
streaming technique chosen by the client.

6. Video Streaming
 The term streaming is associated to digital media (such as
an audio / video stream) to reveal the act of dismissing the
media stream from a server to a client.
 Diverse multimedia streaming services like YouTube, Hulu,
Veoh etc.
 Challenges for Video Streaming
 Bandwidth
 Delay
 Loss
 Forward Error Control (FEC)
 Retransmission
 Error Concealment
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7. Streaming Protocols
 Real Time Streaming Protocol (RTSP)
 RFC 2326
 VCR like functionality
 Session Description Protocol (SDP)
 RFC 2327
 Defines procedure for describing session parameters.
 Real Time Protocol (RTP)
 Real Time Control Protocol (RTCP)
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8. Scalable video server architecture
Figure 3.1: A Scalable Video Server Architecture [57]
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9. Yima system architecture
Figure 3.2: Yima system architecture [58]
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10. Elvira video server architecture
Figure 3.3: Elvira video server architecture [59]
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11. Flash Media Server
Figure 3.5: Adobe streaming server architecture [46]
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13. Design of Distribution Agnostic
Video Server (DAVS)
 Video server is based on a modular design, and is
composed by a set of components
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14. Design of Distribution Agnostic
Video Server (DAVS) contd.
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16. DAVS API
 DAVS API is implemented by the streaming
engine through a set of 5 scripts
 Validate
 Import
 Start
 Stop
 Deport
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17. Validate
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18. Import
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19. Start
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20. Deport
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22. DAVS Database
 Used MYSQL
 Provides variety of
connectors to
interact with the
MYSQL data base
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24. Video server interface
 Video server interface is the focal entry point
into a system.
 Dual Responsibilities
 Invoke DAVS API
 Communicate with the DAVS client
 RPC mechanism is used between DAVS client
and video server interface.
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26. DAVS Client
 Pure Java base application
 DAVS client has two profile
 User profile
 Admin profile
 Fetch all available streams from the DAVS
 Interact with DAVS through RPC mechanism.
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27. DAVS Client contd.
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29. DAVS Architecture
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31. Testing Objective
 Test the engine agnostic functionality of the video
server
 Measure the utilization of hardware resources of the
DAVS.
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32. DAVS Testing
 Tested with two
streaming engines
 Tools used in the
experiments for
system monitoring
 sar
 ifstat
 dstat
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33. Performance metrics
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34. Performance metrics (contd.)

35. Advantages of DAVS
 Advantages
 Single video server that can plug in different streaming
engines.
 Minimize the cost of video servers.
 Low maintenance and management cost.
 Disadvantages
 Single point of failure
 Current implementation of DAVS API only supports
Linux and Unix platforms.
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36. Conclusion
 Design a video server that can plug in different
streaming engines.
 Tested the engine agnostic functionality in a live test
bed.
 Source code is available on git under GPL license
version 2.
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37. Future work
 Plug in for P2P streaming
 Scalability issues
 Should be tested with more streaming engines.
 HTTP interface for DAVS
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38. Thanks.