02.10.2013 Views

FTOS Configuration Guide for the C-Series - Force10 Networks

FTOS Configuration Guide for the C-Series - Force10 Networks

FTOS Configuration Guide for the C-Series - Force10 Networks

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Chapter 29<br />

Internet Group Management Protocol is supported only on plat<strong>for</strong>ms: c e<br />

IGMP Snooping versions 1 and 2 are supported on plat<strong>for</strong>ms: c e s<br />

IGMP Snooping version 3 is supported only on plat<strong>for</strong>m e<br />

Multicast is premised on identifying many hosts by a single destination IP address; hosts represented by<br />

<strong>the</strong> same IP address are a multicast group. Internet Group Management Protocol (IGMP) is a Layer 3<br />

multicast protocol that hosts use to join or leave a multicast group. Multicast routing protocols (such as<br />

PIM) use <strong>the</strong> in<strong>for</strong>mation in IGMP messages to discover which groups are active and to populate <strong>the</strong><br />

multicast routing table.<br />

IGMP Implementation In<strong>for</strong>mation<br />

• <strong>FTOS</strong> supports IGMP versions 1, 2, and 3 based on RFCs 1112, 2236, and 3376, respectively.<br />

• E-<strong>Series</strong> E<strong>the</strong>rScale supports IGMP only on physical interfaces.<br />

• C-<strong>Series</strong> does not support IGMP on port-channels.<br />

• IGMP version 3 is supported only on E-<strong>Series</strong>.<br />

• <strong>FTOS</strong> does not support IGMP version 3 and versions 1 or 2 on <strong>the</strong> same subnet.<br />

• IGMP version 3 on <strong>FTOS</strong> supports up to 512 interfaces and an unlimited number of groups.<br />

• <strong>Force10</strong> systems cannot serve as an IGMP host or an IGMP version 1 IGMP Querier.<br />

• <strong>FTOS</strong> automatically enables IGMP on interfaces on which you enable a multicast routing protocol.<br />

IGMP Protocol Overview<br />

IGMP has three versions. Version 3 obsoletes and is backwards-compatible with version 2; version 2<br />

obsoletes version 1.<br />

IGMP version 2<br />

Internet Group Management<br />

Protocol<br />

IGMP version 2 improves upon version 1 by specifying IGMP Leave messages, which allows hosts to<br />

notify routers that <strong>the</strong>y no longer care about traffic <strong>for</strong> a particular group. Leave messages reduce <strong>the</strong><br />

amount of time that <strong>the</strong> router takes to stop <strong>for</strong>warding traffic <strong>for</strong> a group to a subnet (leave latency) after<br />

<strong>the</strong> last host leaves <strong>the</strong> group. In version 1 hosts quietly leave groups, and <strong>the</strong> router waits <strong>for</strong> a query<br />

response timer several times <strong>the</strong> value of <strong>the</strong> query interval to expire be<strong>for</strong>e it stops <strong>for</strong>warding traffic.<br />

<strong>FTOS</strong> <strong>Configuration</strong> <strong>Guide</strong>, version 7.7.1.0 583

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!