Lantech LGS-2816C-RPS, User Manual

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C
ONFIGURING
M
ULITCAST
P
ROTOCOL
The function, is used to establish the multicast groups to forward
the multicast packet to the member ports, and, in nature, avoids
wasting the bandwidth while IP multicast packets are running over
the network. This is because a switch that does not support IGMP
or IGMP Snooping can not tell the multicast packet from the
broadcast packet, so it can only treat them all as the broadcast
packet. Without IGMP Snooping, the multicast packet forwarding
function is plain and nothing is different from broadcast packet.
A switch supported IGMP Snooping with the functions of query,
report and leave, a type of packet exchanged between IP Multicast
Router/Switch and IP Multicast Host, can update the information of
the Multicast table when a member (port) joins or leaves an IP
Multicast Destination Address. With this function, once a switch
receives an IP multicast packet, it will forward the packet to the
members who joined in a specified IP multicast group before.
The packets will be discarded by the IGMP Snooping if the user
transmits multicast packets to the multicast group that had not
been built up in advance.
W
EB
I
NTERFACE
To display the set of the IGMP Mode:
1.
Click IGMP, Mode.
2.
Scroll to choice IGMP mode (Default is Disable).
3.
Click Apply
Figure 4-84: Set the IGMP MODE
IGMP MODE
CONFIGURATION
IGMP mode enables the switch to issue IGMP function that you
enable IGMP proxy or snooping on the switch, which connects to a
router closer to the root of the tree. This interface is the upstream
interface. The router on the upstream interface should be running
IGMP.