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Lantronix
SM24TBT2DPA and SM24TBT2DPB Web User Guide
2-11 IPMC
ICMP (Internet Control Message Protocol) is a protocol that generated the error response, diagnostic or
routing purposes. ICMP messages generally contain information about routing difficulties or simple
exchanges such as time-stamp or echo transactions.
2-11.1 IGMP Snooping
This function is used to establish the multicast groups to forward the multicast packet to the member ports,
and, by nature, avoid 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 cannot 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 supporting 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. 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.
2-11.1.1 Basic Configuration
This page lets you set basic IGMP 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.
Web Interface
To configure IGMP Snooping parameters in the web UI:
1. Click Configuration, IPMC, IGMP Snooping, Basic Configuration.
2. Enable or disable IPMC globally.
3. Select which port is to become a Router Port or enable/ disable the Fast Leave function.
4. At the Throttling dropdown, select the Throttling parameter.
5. Click the Apply button to save the settings.
6. To cancel the settings, click the Reset button. The page will revert to previously saved values.