Igmp Versions; Igmp Version 1 - Cisco Catalyst 3650 Configuration Manual

Configuring IGMP
• IGMP Version 2 (IGMPv2) leave messages are destined to the address 224.0.0.2 (all multicast routers
Related Topics
Configuring the Device as a Member of a Group (CLI), on page 34
Example: Configuring the Device as a Member of a Multicast Group, on page 81

IGMP Versions

The device supports IGMP version 1, IGMP version 2, and IGMP version 3. These versions are interoperable
on the device. For example, if IGMP snooping is enabled and the querier's version is IGMPv2, and the device
receives an IGMPv3 report from a host, then the device can forward the IGMPv3 report to the multicast router.

IGMP Version 1

IGMP version 1 (IGMPv1) primarily uses a query-response model that enables the multicast router and
multilayer device to find which multicast groups are active (have one or more hosts interested in a multicast
group) on the local subnet. IGMPv1 has other processes that enable a host to join and leave a multicast group.
For more information, see RFC 1112.
IGMP Version 2
IGMPv2 extends IGMP functionality by providing such features as the IGMP leave process to reduce leave
latency, group-specific queries, and an explicit maximum query response time. IGMPv2 also adds the capability
for routers to elect the IGMP querier without depending on the multicast protocol to perform this task. For
more information, see RFC 2236.
IGMP version 2 is the default version for the device.
Note
IGMP Version 3
The device supports IGMP version 3. The following are considerations for the device and IGMP version 3:
• An IGMPv3 device supports Basic IGMPv3 Snooping Support (BISS), which includes support for the
• The device supports IGMPv3 snooping based only on the destination multicast IP address. It does not
• IGMPv3 join and leave messages are not supported on devices running IGMP filtering or Multicast
OL-29890-01
on a subnet). In some old host IP stacks, leave messages might be destined to the group IP address rather
than to the all-routers address.
snooping features on IGMPv1 and IGMPv2 switches and for IGMPv3 membership report messages.
BISS constrains the flooding of multicast traffic when your network includes IGMPv3 hosts. It constrains
traffic to approximately the same set of ports as the IGMP snooping feature on IGMPv2 or IGMPv1
hosts.
support snooping based on a source IP address or proxy report.
VLAN registration (MVR).
IP Multicast Routing Configuration Guide, Cisco IOS XE Release 3SE (Catalyst 3650 Switches)
IGMP Versions
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