CHAPTER 15: IGMP IGMP
MULTILINK ML2400 ETHERNET COMMUNICATIONS SWITCH – INSTRUCTION MANUAL 15–5
15.1.4 Reserved Addresses Excluded from IP Multicast (IGMP) Filtering
Traffic to IP multicast groups in address range 224.0.0.0 to 224.0.0.255 will always be
flooded because addresses in this range are “well known” or “reserved”. Thus, if IP Multicast
is enabled and there is an IP multicast group within the reserved address range, traffic to
that group will be flooded instead of filtered by the switch.
15.1.5 IGMP Support
The MultiLink family of switches support IGMP version 1 and version 2. The switch can act
either as a querier or a nonquerier. The querier router periodically sends general query
messages to solicit group membership information. Hosts on the network that are
members of a multicast group send report messages. When a host leaves a group, it sends
a leave group message. The difference between Version 1 and Version 2 is that version 1
does not have a “Leave” mechanism for the host. The MultiLink family of switches do
pruning when there is a leave message or a time expires on a port, we prune the multicast
group membership on that port.
1. The MultiLink switch supports only the default VLAN. It can be enabled within a
port VLAN, tagged VLAN, or no VLAN. It can snoop up to 256 multi-cast
Groups.
2. IGMP is disabled as a default. It has to be enabled to leverage the benefits of
IGMP.
3. The MultiLink switch supports only the default VLAN. It can be enabled within a
port VLAN, tagged VLAN, or no VLAN. It can snoop up to 256 multi-cast
Groups.
4. IGMP works only on default VLAN (DEFAULT_VLAN or VID = 1).