User Manual
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(Figure 5.7.1.5)
:
VLAN maximum support 64 VLAN item, VID value range:1~4095
Manged port is the port that manage and configure switch, it must in a same VLAN as CPU port
5.7.2 IGMP snooping
IP host applies to join (or leave) multicast group to the neighboring router through IGMP (Internet Group
Management Protocol) protocol. IGMP Snooping is multicast constraining mechanism. It manages and
controls multicast group by snooping and analysis of the IGMP messages between the host and the
multicast device.
Work process of IGMP Snooping: the switch snoops messages between the host computer and the
router and tracks multicast information and the port applied for. When the switch snoops IGMP Report
message sent from the host computer to the router, the switch would add this port to multicast
forwarding list; when the switch snoops IGMP Leave message sent by the host computer, the router will
send Group-Specific Query message of this port. If other hosts need this multicast, then the rely IGMP
Report message. If the router doesn't get any reply from the hosts, the switch would delete this port from
the multicast forwarding list. The router will send IGMP Query message regularly, the switch will deletes
the port from the multicast forwarding list if it doesn't get the IGMP Report message from the host.
IGMP Snooping:
Enable or disable IGMP snooping function
IGMP Query:
Enable or disable IGMP query function
IGMP Query Interval:
after
enabling IGMP Query, the interval to check existing multicast members.
MAX Age:
the maximum existing time of the members
(Figure 5.7.2.1 )
1. Must configure the VLAN of 802.1q at first, then open IGMP Snooping function
2. Please do not open more IGMP snooping, waste source.
5.7.3 Static Multicast
