I nt roduct ion St reaming video of t en does not like TCP Want s - - PowerPoint PPT Presentation

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I nt roduct ion St reaming video of t en does not like TCP Want s - - PowerPoint PPT Presentation

Jun 08, 2023 263 likes •409 views

MediaPlayer vs. RealPlayer A Comparison of Network Turbulence Mingzhe Li, Mark Claypool, Robert Kinicki CS Depart ment Worcest er Polyt echnic I nst it ut e Worcest er, MA, USA http://perform.wpi.edu/ I nt roduct ion St reaming

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SLIDE 1

MediaPlayer ™ vs. RealPlayer ™

A Comparison of Network Turbulence

Mingzhe Li, Mark Claypool, Robert Kinicki

CS Depart ment Worcest er Polyt echnic I nst it ut e Worcest er, MA, USA

http://perform.wpi.edu/

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SLIDE 2

November 2002 SI GCOMM I nt ernet Measurement Workshop

I nt roduct ion

  • St reaming video of t en does not like TCP

– Want s smoot h st r eam, so r at e-based – Does not always want r et ransmissions !Chooses UDP

  • UDP f lows may be unresponsive t o congest ion

!Handle wit h Act ive Queue Management (AQM)

  • Typical AQMs model UDP f lows as CBR (“f irehose”)
  • More realist ic models of st reaming UDP f lows will

make AQMs more ef f ect ive

  • We invest igat e size and dist ribut ion over t ime

! Turbulence

  • Big 3: RealPlayer, MediaPlayer, QuickTime [J up01]
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SLIDE 3

November 2002 SI GCOMM I nt ernet Measurement Workshop

Met hodology

  • Build aut omat ed video players

(MediaTr acker and RealTr acker [WCZ01])

– Use commercial cores – Sof t ware Development Kit s (SDKs) – Record applicat ion st at s: f rame rat e…

  • Select host s wit h bot h RealNet wor ks and

Microsof t Media video servers

  • St ream ident ical cont ent t o players on t he

same host

  • Analyze result s
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SLIDE 4

November 2002 SI GCOMM I nt ernet Measurement Workshop

Clip Select ion

Real Microsof t Type Bandwidth (Kbps) (Kbps) 1 Sport s High 284 323 3:46 Low 36 50 2 Commercial High 268 307 0:39 Low 84 102 3 Sport s High 284 307 0:60 Low 37 38 4 Music T.V. High 181 309 4:05 Low 26 50 5 News High 218 250 1:47 Low 22 39 6 Movie Clip Very High 637 731 2:27 High 271 347 Low 39 102

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SLIDE 5

November 2002 SI GCOMM I nt ernet Measurement Workshop

Experiment al Set up

  • Player Plat f orm

– Microsof t Windows 2000 PC – P4 1.8 GHz, 512M RAM, AGP 32MB video card – mindspeed.wpi.edu (Worcest er, MA, USA)

  • Net work

– LAN: PCI 10M NI C Win2k prof essional – Campus uplink: ~50 Mbps (Yipes in 15 Mbps)

  • Sof t ware

– Microsof t Media Player version 7.1 – RealNet wor ks RealOne Player build 6.0.10.505 – Et hereal version 0.8.20

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SLIDE 6

November 2002 SI GCOMM I nt ernet Measurement Workshop

1720 1725 1730 1735 1740 1745 1750 1755 1760 30 30.2 30.4 30.6 30.8 31

Time (Seconds)

Real Packet Number 790 795 800 805 810 815 820 825 830 Media Packet Number

Real Play (217K) Windows Media Player (250K)

I P Packet Arrivals

  • RealPlayer – single packet s
  • Media Player – groups of packet s (3 in t his example)

– 2 at about 1500 byt es (t ypical MTU) – 1 “lef t -over” less t han MTU

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SLIDE 7

November 2002 SI GCOMM I nt ernet Measurement Workshop

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 200 400 600 800

Encoded Bandwidth (Kbits/ s) I P Packet s w/ out UDP Header

Media Player I P Packet Fragment at ion

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SLIDE 8

November 2002 SI GCOMM I nt ernet Measurement Workshop

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.5 1 1.5 2

Normalized Packet size Probabilit y Densit y

Real Player Windows Media

Normalized UDP Packet Sizes

Media Player – More “Const ant Packet Size” RealPlayer – Less “Const ant Packet Size”

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SLIDE 9

November 2002 SI GCOMM I nt ernet Measurement Workshop

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.5 1 1.5 2 2.5 3

Normalized I nterarrival Time I nterval Cumulative Density

Real Player Window Media Player

UDP Packet I nt erarrival Times

Media Player – More “Const ant Packet Rat e” RealPlayer – Less “Const ant Packet Rat e”

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SLIDE 10

November 2002 SI GCOMM I nt ernet Measurement Workshop

100 200 300 400 500 600 700 50 100 150 200 250

Time (seconds) Bandwidth (Kbits/ sec. )

Real Player (284K) Real Player (36K) Windows Media Player (323K) Windows Media Player (49K)

Playout Rat e

RealPlayer buffers at a higher rate

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SLIDE 11

November 2002 SI GCOMM I nt ernet Measurement Workshop

Frame Rat e

5 10 15 20 25 30 35 200 400 600 800

Average Bandwidth (Kbits/ sec.)

Frame Rate (f ps)

Real Player Media Player

RealPlayer signif icant ly higher at low bandwidt h

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SLIDE 12

November 2002 SI GCOMM I nt ernet Measurement Workshop

Summary

  • Microsof t Media Player t ypical CBR

– Const ant packet sizes and int erarrivals

  • RealNet works RealPlayer less CBR

– Range of packet sizes and int erarrivals – Buf f ers at up t o 3 t imes playout rat e

  • Media Player has signif icant I P f r ag.

– 3-5 I P f rags / UDP f or broadband+ bwidt h

  • Result s can be used f or more realist ic

st r eaming simulat ions and emulat ions

  • MediaTracker and RealTr acker online:

http://perform.wpi.edu/real-tracer/

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SLIDE 13

November 2002 SI GCOMM I nt ernet Measurement Workshop

Fut ure Work

  • Build simulat ed st reaming applicat ion

– I n NS

  • Server side cont rol

– Clip encoding, Cont ent t ype – (We have server set -up, preliminary result s)

  • Bandwidt h under congest ion

– TCP-Friendly? – (We have result s f or RealPlayer)

  • More players and prot ocols

– QuickTime (QuickTracker)

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SLIDE 14

MediaPlayer ™ vs. RealPlayer ™

A Comparison of Network Turbulence

Mingzhe Li, Mark Claypool, Robert Kinicki

CS Depart ment Worcest er Polyt echnic I nst it ut e Worcest er, MA, USA

http://perform.wpi.edu/