Allied Telesis AT-S63 - Manual (Page 237)

AT-S63 Management Software Menus Interface User’s Guide
Section II: Advanced Features 237
3. Adjust the following parameters as necessary:
1 - IGMP Snooping Status
Enables or disables IGMP snooping on the switch. After you
choose this selection, type E to enable to D to disable this feature.
2 - Multicast Host Toplogy
Defines whether there is only one host node per switch port or
multiple host nodes per port. Possible settings are:
Single-Host/Port (Edge)
The Single-Host/Port setting is appropriate when there is only one
host node connected to each port on the switch. This setting
causes the switch to immediately stop sending multicast packets
out a switch port when a host node signals its desire to leave a
multicast group by sending a leave request or when the host node
stops sending reports. The switch responds by immediately
ceasing the transmission of additional multicast packets out the
port where the host node is connected.
Multiple Host/Ports (Intermediate)
The Multi-Host setting is appropriate if there is more than one
host node connected to a switch port, such as when a port is
connected to an Ethernet hub to which multiple host nodes are
connected. With this setting selected the switch continues
sending multicast packets out a port even after it receives a leave
request from a host node on the port. This ensures that the
remaining active host nodes on the port continue to receive the
multicast packets. Only after all the host nodes connected to a
switch port have transmitted leave requests or have timed out
does the switch stop sending multicast packets out the port.
If a switch has a mixture of host nodes, that is, some connected
directly to the switch and others through an Ethernet hub, you
should select the Multi-Host Port (Intermediate) selection.
3 - Host/Router Timeout Interval
Specifies the time period in seconds at which the switch
determines that a host node has become inactive. An inactive
host node is a node that has not sent an IGMP report during the
specified time interval. The range is from 1 second to 86,400
seconds (24 hours). The default is 260 seconds.
This parameter also specifies the time interval used by the switch
in determining whether a multicast router is still active. The switch
makes the determination by watching for queries from the router.
If the switch does not detect any queries from a multicast router
during the specified time interval, it assumes that the router is no
longer active on the port.