User Manual

AT-S62 Management Software Web Browser Interface User’s Guide
Section II: Advanced Operations 185
router and simultaneously ceases transmission of any further multicast
packets out the port where the host node is connected.
The Intermediate (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 of 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 Intermediate Multi-Host Port selection.
Multicast Router Ports Mode
Specifies whether the router ports will be determined automatically or if
you will enter them manually. If you want the switch to determine the
ports automatically, select Auto-Detect, which is the default. To enter
them yourself, click Manual Select and enter the ports in the field.
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 0 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specified time interval, it assumes that the router is no longer active on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.
The actual timeout may be ten seconds less that the specified value.
For example, a setting of 25 seconds can result in the switch
classifying a host node or multicast router as being inactive after just
15 seconds. A setting of 10 seconds or less can result in the
immediate timeout of an inactive host node or router.
A value of 0 disables the timer. A switch with a disabled timer never
times out inactive host nodes or multicast routers.
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.