Master Thesis Presentation

Waqas Daar (daar@kth.se)

School of Information and Communication TechnologyRoyal Institute of Technology (KTH)

Stockholm, Sweden

Examiner : Markus HaidelSupervisor: Renato Lo Cigno

University of Trento, Italy

Opponent : Waqas WarraichDate: May 17, 2010

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

2

Motivation

New multimedia streaming applications are not immune to interaction with the current Internet and client server model.

To compare distinct streaming technologies.

4

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.

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

6

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)

7

8

Scalable video server architecture

Figure 3.1: A Scalable Video Server Architecture [57]

9

Yima system architecture

Figure 3.2: Yima system architecture [58]

10

Elvira video server architecture

Figure 3.3: Elvira video server architecture [59]

11

Flash Media Server

Figure 3.5: Adobe streaming server architecture [46]

Design of Distribution Agnostic Video Server (DAVS) Video server is based on a modular design, and is

composed by a set of components

13

Design of Distribution Agnostic Video Server (DAVS) contd.

14

DAVS API

DAVS API is implemented by the streaming engine through a set of 5 scripts

Validate

Import

Start

Stop

Deport

16

17

Validate

Import

18

Start

19

Deport

20

DAVS Database

22

Used MYSQL

Provides variety of connectors to interact with the MYSQL data base

Video server interface

24

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.

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.

26

DAVS Client contd.

27

DAVS Architecture

29

Testing Objective Test the engine agnostic functionality of the video

server

Measure the utilization of hardware resources of the DAVS.

31

DAVS Testing

32

Tested with two streaming engines

Tools used in the experiments for system monitoring

sar

ifstat

dstat

Performance metrics

33

Performance metrics (contd.)

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.

35

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.

36

Future work

Plug in for P2P streaming

Scalability issues

Should be tested with more streaming engines.

HTTP interface for DAVS

37

Thanks.