Internet Group Management Protocol (IGMP)
Internet group management protocol (IGMP) is a Layer 3 multicast protocol that hosts use to join or leave a multicast group.
Multicast is premised on identifying many hosts by a single destination IP address; hosts represented by the same IP address are a multicast
group. Multicast routing protocols (such as protocol-independent multicast [PIM]) use the information in IGMP messages to discover
which groups are active and to populate the multicast routing table.
IGMP Implementation Information
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Dell Networking Operating System (OS) supports IGMP versions 1, 2, and 3 based on RFCs 1112, 2236, and 3376, respectively.
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Dell Networking OS does not support IGMP version 3 and versions 1 or 2 on the same subnet.
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IGMP on Dell Networking OS supports an unlimited number of groups.
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Dell Networking systems cannot serve as an IGMP host or an IGMP version 1 IGMP Querier.
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Dell Networking OS automatically enables IGMP on interfaces on which you enable a multicast routing protocol.
Topics:
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Viewing IGMP Enabled Interfaces
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Preventing a Host from Joining a Group
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Fast Convergence after MSTP Topology Changes
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Egress Interface Selection (EIS) for HTTP and IGMP Applications
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Designating a Multicast Router Interface
IGMP Protocol Overview
IGMP has three versions. Version 3 obsoletes and is backwards-compatible with version 2; version 2 obsoletes version 1.
IGMP Version 2
IGMP version 2 improves on version 1 by specifying IGMP Leave messages, which allows hosts to notify routers that they no longer care
about traffic for a particular group.
Leave messages reduce the amount of time that the router takes to stop forwarding traffic for a group to a subnet (leave latency) after the
last host leaves the group. In version 1 hosts quietly leave groups, and the router waits for a query response timer several times the value of
the query interval to expire before it stops forwarding traffic.
To receive multicast traffic from a particular source, a host must join the multicast group to which the source is sending traffic. A host that
is a member of a group is called a receiver. A host may join many groups, and may join or leave any group at any time. A host joins and
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Internet Group Management Protocol (IGMP)
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Summary of Contents for S4048T-ON
Page 1: ...Dell Configuration Guide for the S4048 ON System 9 11 2 1 ...
Page 148: ...Figure 10 BFD Three Way Handshake State Changes 148 Bidirectional Forwarding Detection BFD ...
Page 251: ...Dell Control Plane Policing CoPP 251 ...
Page 363: ... RPM Synchronization GARP VLAN Registration Protocol GVRP 363 ...
Page 511: ...Figure 64 Inspecting the LAG Configuration Link Aggregation Control Protocol LACP 511 ...
Page 558: ...Figure 84 Configuring Interfaces for MSDP 558 Multicast Source Discovery Protocol MSDP ...
Page 559: ...Figure 85 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 559 ...
Page 564: ...Figure 88 MSDP Default Peer Scenario 2 564 Multicast Source Discovery Protocol MSDP ...
Page 565: ...Figure 89 MSDP Default Peer Scenario 3 Multicast Source Discovery Protocol MSDP 565 ...
Page 841: ...Figure 115 Single and Double Tag TPID Match Service Provider Bridging 841 ...
Page 842: ...Figure 116 Single and Double Tag First byte TPID Match 842 Service Provider Bridging ...