Allied Telesis AT-S39 - Manual (Page 147)

AT-S39 User’s Guide
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multicast group by sending a leave request or when the host node
stops sending reports. The switch responds by immediately
ceasing the transmission of further multicast packets out the port
where the host node is connected.
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 will 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)
will 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 after 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during the specified time interval, it assumes that the router is no
longer active on the port.
4 - Maximum Multicast Groups
Specifies the maximum number of multicast groups the switch
will learn. The range is 1 to 2048 groups. The default is 256
multicast groups.
This parameter is useful with networks that contain a large
number of multicast groups. You can use the parameter to
prevent the switch’s MAC address table from filling up with
multicast addresses, leaving no room for dynamic or static MAC
addresses. The range is 1 address to 2048 addresses. The default is
256 multicast addresses.