Multicast After 9112001 NANOG 23

1
Multicast After 9/11/2001NANOG 23

• Marshall Eubanks
• tme_at_multicasttech.com
• Rich Mavrogeanes
• rmavro_at_Vbrick.com
• Prashant Rajvaidya
• prash_at_cs.ucsb.edu

2
Internet News Melt-down9/11/2001

• Web Site Performance 900 AM to 1000 AM
• Site Users able to access
• ABCNews.com 0
• CNN.com 0
• NYTimes.com 0
• USAToday.com 18
• MSNBC.com 22
• (source Keynotes Business Performance /
• Interactive Week 9/17/2001)

3
Internet News Performance 9/11/2001

• Of course, the melt-down was caused by the
  incredible demand for news after the attacks.
• Unicast Streaming web sites suffered similar
  problems, at least from anecdotal evidence
• By contrast, multicast performed well
• Large Increase in traffic
• Roughly 1 Gigabit per second saved at peak
• Over time, the multicast peering mesh degraded,
  but this was NOT due to increased traffic

4
Eyewitness Accounts

• We had a large plasma screen in the iLabs at
  NetworldInterop intended to demonstrate high
  rate HDTV over I2. We came in Tuesday morning and
  were preparing for the first day of the show when
  word came in about the initial plane crash into
  the towers. Our I2 Lead, Roy Hockett was able to
  switch the stream to a CNN broadcast from UMich.
  We began attracting exhibitors to the display
  even before the showfloor opened. Once the
  attendees were on the floor, the crowd had grown
  to well over a hundred.
• By this point, three things had happened. The
  crowds around the one display had grown so large
  as to constitute a fire hazard, all the major
  news web sites had completely melted down, and
  CNN was being multicast from several sources. We
  then started loading multicast tools on every PC
  in the NOC, from the one driving the large video
  wall to people's individual laptops. By 1030
  (about half an hour after the floor opened) we
  had at least 3 large displays as well as a number
  of normal monitors turned out towards the
  plexiglass walls.
• Soon after, we had a good number of exhibitors
  come and ask how to get "the CNN viewer
  software".
• Jim Martin, ltjrm_at_nortelnetworks.comgt
• More than 1,000 copies of StreamPlayerII, our
  multicast MPEG viewer, were downloaded or handed
  out on disk between 9/11 and 9/12. We normally
  average 20 to 100 per day.
• Rich Mavrogeanes ltrmavro_at_vbrick.comgt

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Viewership

• Sudden increase in Multicast traffic of at least
  1000 group members
• Mostly viewing VBricks television broadcast
• Measured Viewership gt 830
• But each measured point could have many
  individual viewers since they multicast locally
• BANDWIDTH SAVED IN EXCESS OF 1 GIGABIT / SEC. VS
  UNICAST

Crowds viewing the 9/11 multicasts at
NetworldInterop
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Multicast Activityat FIX-West / Mantra
Purple is of group members
9/11 attack
Note that extra traffic seems to be mostly US -
also not all multicast traffic is visible to
Mantra Attack traffic spurt was so rapid and
unusual that we first thought it was a MSDP storm
! from http//www.caida.org/tools/measurement/Mant
ra/session-mon/session-mon.html
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Multicast Receivers Week of 9/10
9/11 attack
Two independent monitoring efforts on two coasts
saw very similar audience bursts after the
attacks
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Multicast Receivers in September
9/11 attack
9/11 attack
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Multicast Activity on 9/11 and after

• Sudden increase in Mantra traffic of gt
  1000 group members
• Most of these seem to be television viewers
• Known TV viewership gt 830
• Bandwidth saved approaches or exceeds 1 Gigabit
  / sec.
• Performance as seen from MCT was good.

10
The Stability of Multicast

• How did Multicast Connectivity behave under the
  attack?
• We (Multicast Technologies) monitor multicast
  connectivity as seen by MBGP from our AS.
• There were no apparent problems on 9/11
• However, there were problems starting on 9/13
  when the backup power for 25 Broadway went down.
• Our connectivity suffered from this.

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Multicast Redundancy

• We (Multicast Technologies) have 3 connections
  into the multicast enabled Internet.
• Of the 4642 MBGP prefixes advertised to us
  recently, 28 had only one route !
• Number Routes Number Prefixes
• 1 1280 28
• 2 2445 53
• 3 917 20

The Multicast Mesh Needs to be More Robust
12
Multicast As the Generators Ran Out
lt 25 Broadway Failure
Attack
Alternate Access through AUCS
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Conclusions

• Multicast Met a Real Need after the 9/11 attacks
• Over 800 video users (at least)
• 1 Gigabit / sec of bandwidth saved (at least)
• Multicast passed its baptism under fire
• Availability when other sites were spotty at best
• The Multicast mesh and peering need to be made
  more robust.