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IGMP Commands
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IGMP Commands
Internet Group Management Protocol (IGMP) is the multicast group
membership discovery protocol used for IPv4 multicast groups. Three
versions of IGMP exist. Versions one and two are widely deployed. Since
IGMP is used between end systems (often desktops) and the multicast router,
the version of IGMP required depends on the end-user operating system
being supported. Any implementation of IGMP must support all earlier
versions.
The following list describes the basic operation of IGMP, common to all
versions. A multicast router can act as both an IGMP host and an IGMP
router and as a result can respond to its own IGMP messages. The
PowerConnect implementation of IGMPv3 supports the multicast router
portion of the protocol (that is, not the host portion). It is backward
compatible with IGMPv1 and IGMPv2.
• One router periodically broadcasts IGMP Query messages onto the
network.
• Hosts respond to the Query messages by sending IGMP Report messages
indicating their group memberships.
• All routers receive the Report messages and note the memberships of hosts
on the network.
• If a router does not receive a Report message for a particular group for a
period of time, the router assumes there are no more members of the
group on the network.
All IGMP messages are raw IP data grams and are sent to multicast group
addresses, with a time to leave (TTL) of 1. Since raw IP does not provide
reliable transport, some messages are sent multiple times to aid reliability.
IGMPv3 is a major revision of the protocol and provides improved group
membership latency. When a host joins a new multicast group on an
interface, it immediately sends an unsolicited IGMP Report message for that
group.
2CSPC4.XCT-SWUM2XX1.book Page 925 Monday, October 3, 2011 11:05 AM
Summary of Contents for PowerConnect 7000 Series
Page 74: ...74 Contents 2CSPC4 XCT SWUM2XX1 book Page 74 Monday October 3 2011 11 05 AM ...
Page 164: ...164 Command Groups 2CSPC4 XCT SWUM2XX1 book Page 164 Monday October 3 2011 11 05 AM ...
Page 266: ...266 AAA Commands 2CSPC4 XCT SWUM2XX1 book Page 266 Monday October 3 2011 11 05 AM ...
Page 316: ...316 Auto VoIP Commands 2CSPC4 XCT SWUM2XX1 book Page 316 Monday October 3 2011 11 05 AM ...
Page 368: ...368 DHCP Snooping Commands 2CSPC4 XCT SWUM2XX1 book Page 368 Monday October 3 2011 11 05 AM ...
Page 454: ...454 Ethernet CFM Commands 2CSPC4 XCT SWUM2XX1 book Page 454 Monday October 3 2011 11 05 AM ...
Page 468: ...468 Green Ethernet Commands 2CSPC4 XCT SWUM2XX1 book Page 468 Monday October 3 2011 11 05 AM ...
Page 558: ...558 IP Source Guard Commands 2CSPC4 XCT SWUM2XX1 book Page 558 Monday October 3 2011 11 05 AM ...
Page 578: ...578 Link Dependency Commands 2CSPC4 XCT SWUM2XX1 book Page 578 Monday October 3 2011 11 05 AM ...
Page 606: ...606 LLDP Commands 2CSPC4 XCT SWUM2XX1 book Page 606 Monday October 3 2011 11 05 AM ...
Page 700: ...700 QoS Commands 2CSPC4 XCT SWUM2XX1 book Page 700 Monday October 3 2011 11 05 AM ...
Page 728: ...728 RADIUS Commands 2CSPC4 XCT SWUM2XX1 book Page 728 Monday October 3 2011 11 05 AM ...
Page 808: ...808 VLAN Commands 2CSPC4 XCT SWUM2XX1 book Page 808 Monday October 3 2011 11 05 AM ...
Page 814: ...814 Voice VLAN Commands 2CSPC4 XCT SWUM2XX1 book Page 814 Monday October 3 2011 11 05 AM ...
Page 848: ...848 802 1x Commands 2CSPC4 XCT SWUM2XX1 book Page 848 Monday October 3 2011 11 05 AM ...
Page 850: ...850 Layer 3 Commands 2CSPC4 XCT SWUM2XX1 book Page 850 Monday October 3 2011 11 05 AM ...
Page 912: ...912 DHCPv6 Commands 2CSPC4 XCT SWUM2XX1 book Page 912 Monday October 3 2011 11 05 AM ...
Page 920: ...920 DVMRP Commands 2CSPC4 XCT SWUM2XX1 book Page 920 Monday October 3 2011 11 05 AM ...
Page 946: ...946 IGMP Proxy Commands 2CSPC4 XCT SWUM2XX1 book Page 946 Monday October 3 2011 11 05 AM ...
Page 1062: ...1062 IPv6 Routing Commands 2CSPC4 XCT SWUM2XX1 book Page 1062 Monday October 3 2011 11 05 AM ...
Page 1174: ...1174 OSPF Commands 2CSPC4 XCT SWUM2XX1 book Page 1174 Monday October 3 2011 11 05 AM ...
Page 1234: ...1234 OSPFv3 Commands 2CSPC4 XCT SWUM2XX1 book Page 1234 Monday October 3 2011 11 05 AM ...
Page 1294: ...1294 Utility Commands 2CSPC4 XCT SWUM2XX1 book Page 1294 Monday October 3 2011 11 05 AM ...
Page 1304: ...1304 Auto Install Commands 2CSPC4 XCT SWUM2XX1 book Page 1304 Monday October 3 2011 11 05 AM ...
Page 1348: ...1348 CLI Macro Commands 2CSPC4 XCT SWUM2XX1 book Page 1348 Monday October 3 2011 11 05 AM ...
Page 1366: ...1366 Clock Commands 2CSPC4 XCT SWUM2XX1 book Page 1366 Monday October 3 2011 11 05 AM ...
Page 1478: ...1478 RMON Commands 2CSPC4 XCT SWUM2XX1 book Page 1478 Monday October 3 2011 11 05 AM ...
Page 1518: ...1518 Sflow Commands 2CSPC4 XCT SWUM2XX1 book Page 1518 Monday October 3 2011 11 05 AM ...
Page 1578: ...1578 Syslog Commands 2CSPC4 XCT SWUM2XX1 book Page 1578 Monday October 3 2011 11 05 AM ...
Page 1646: ...1646 Telnet Server Commands 2CSPC4 XCT SWUM2XX1 book Page 1646 Monday October 3 2011 11 05 AM ...
Page 1686: ...1686 Web Server Commands 2CSPC4 XCT SWUM2XX1 book Page 1686 Monday October 3 2011 11 05 AM ...
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