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Deployment of IP Multicastin Campus Infrastructures

Kevin Almeroth (almeroth@cs.ucsb.edu)

UC--Santa Barbara

http://www.internet2.edu/multicast/

http://www.cs.ucsb.edu/~almeroth/talks/I2-ATL-01.ppt

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Outline

• multicast protocols overview—see the WWW site

– super-brief overview

• state of deployment

• getting started with deployment

• working group activities

• addendum: router configs—see the WWW site

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source

Unicast

performs routing and forwarding at the same time, and in the source-to-receiver direction

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source

Multicast Routing (and Functions)

routing (path determination) [but in the reverse direction]

packet forwarding and replication

handling dynamic membership---path pruning/grafting

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source

Building the Reverse Path

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source

Building an RP Tree

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source

Forwarding Data

routing (path determination) [but in the reverse direction]

packet forwarding and replication

handling dynamic membership---path pruning/grafting

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source

Question for the Ages

How to find the source(s)?

source

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How to Find the Sources?

• broadcast everywhere

– receivers decide when they do not want the traffic

• any source multicast (ASM) [PIM-SM/MBGP/MSDP/IGMPv2]

– use a rendezvous point (RP)

– receivers send joins along reverse path to RP

– sources send traffic to RP

• source specific multicast (SSM) [PIM/MBGP/IGMPv3]

– require receivers to already know source(s)

– use some out-of-band mechanism

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How MSDP works with PIM-SM

RP

RP

RP

RP

MSDP peer

Physical link

A

B

C D

Receiver

Source

PIM message

MSDP message

SA

SA

SA

JoinJoinJoin

Join

Join

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How SSM Works

Physical link

A

B

C D

Receiver

Source

PIM message

Join

JoinJoin

Join

Join

Join

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State of Deployment

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Status of the Multicast Pieces(Support for IGMPv2 & PIM-SM/MBGP/MSDP)

• network: lots of vendors support multicast routing: Cisco & Juniper then Nortel, Foundry, Lucent, others, etc.

• OSs/kernel: most kernels support functions (IGMPv2)

• applications:

– MBone tools (http://www-mice.cs.ucl.ac.uk/multimedia/software/)

– IPTV, Real, MediaPlayer, and now LOTS others…

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Status of the Multicast Pieces(Support for IGMPv2 & PIM-SM/MBGP/MSDP)

• content:

– UofO (http://videolab.uoregon.edu/)

– GRID (http://www-fp.mcs.anl.gov/fl/accessgrid/)

– ICAIR CSPAN (http://cspan.icair.org/)

– On-the-I (http://www.on-the-i.com/)

– Yahoo (http://www.broadcast.com/broadband/)

– NASA (http://www.nasa.gov/ntv/ntvweb.html)

– UCSB (http://imj.gatech.edu/)

– All the commodity traffic (sdr)

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Status of the Multicast Pieces(Support for IGMPv3 & SSM)

• network: most vendors already support it since functionality in the core has been simplified

• OSs/kernel: test kernels available

– http://videolab.uoregon.edu/projects.html

• applications: lots of talk, but not much action

– http://videolab.uoregon.edu/projects.html

• content: without supporting software/hardware, content is not there

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Status of Deployment

• nice and stable in Abilene (since early 1999)

• some commercial ISPs…

– but typically service is not announced and is not supported

– issues are beginning to be only political/financial (layers 8&9)

• to track multicast deployment and stats…

– see http://imj.ucsb.edu/mantra/

– see http://dast.nlanr.net/projects/beacon/

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Latest Multicast Topology

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The Internet2 (Abilene) Topology

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Site Deployment:

Getting Startedand

Using Multicast

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Deploying Multicast Locally

• experiment with multicast on a local network

• try one- or few-hop multicast topology

• connect to I2

• experiment with advanced applications

• transition to production service

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Resources

• I2 multicast WWW page

– http://www.internet2.edu/multicast/

• I2 multicast mailing list

– send email to listproc@internet2.edu with:

subscribe wg-multicast Your-Name

– in the body of the message

• I2 multicast working group meetings

– at Joint Techs meetings (http://www.ncne.nlanr.net/training/techs/)

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Working Group Activities

• Continue robust backbone service

– track deployment and use

– support Source Specific Multicast (SSM)

– provide support for gigapop and campus deployment

• Increase deployment

– campuses, international and commodity peering

– provide assistance beyond the NOC

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Working Group Activities

• Increase use of multicast

– encourage campuses to offer events

– advertise availability of events to non-geeks

– new service to track events

• Increase variety of applications

– create opportunities to use multicast in novel ways

– new service to track tools/applications

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Conclusions

• Stable backbone

– Key first step

• Deployment in some campuses (low hanging fruit)

• Working on building a robust service

– More than just one-to-many packet delivery

• applications, support, service, etc.

– Lots of issues with legacy infrastructure