ZyXEL Communications XMG1930 Series User Manual page 209

Table 96 Advanced Application > Multicast > IPv4 Multicast > IGMP Snooping (continued)
LABEL DESCRIPTION
* Settings in this row apply to all ports.
Use this row only if you want to make some settings the same for all ports. Use this row first to set
the common settings and then make adjustments on a port-by-port basis.
Changes in this row are copied to all the ports as soon as you make them.
Normal Leave Enter an IGMP normal leave timeout value (from 200 to 6348800) in miliseconds. Select this
option to have the Switch use this timeout to update the forwarding table for the port.
In normal leave mode, when the Switch receives an IGMP leave message from a host on a
port, it forwards the message to the multicast router. The multicast router then sends out an
IGMP Group-Specific Query (GSQ) message to determine whether other hosts connected to
the port should remain in the specific multicast group. The Switch forwards the query message
to all hosts connected to the port and waits for IGMP reports from hosts to update the
forwarding table.
This defines how many seconds the Switch waits for an IGMP report before removing an IGMP
snooping membership entry when an IGMP leave message is received on this port from a
host.
Fast Leave Enter an IGMP fast leave timeout value (from 200 to 6348800) in miliseconds. Select this option
to have the Switch use this timeout to update the forwarding table for the port.
In fast leave mode, right after receiving an IGMP leave message from a host on a port, the
Switch itself sends out an IGMP Group-Specific Query (GSQ) message to determine whether
other hosts connected to the port should remain in the specific multicast group. This helps
speed up the leave process.
This defines how many seconds the Switch waits for an IGMP report before removing an IGMP
snooping membership entry when an IGMP leave message is received on this port from a
host.
Group Limited Select this option to limit the number of multicast groups this port is allowed to join.
Max Group Num. Enter the number of multicast groups this port is allowed to join. Once a port is registered in the
specified number of multicast groups, any new IGMP join report frames is dropped on this
port.
Throttling IGMP throttling controls how the Switch deals with the IGMP reports when the maximum
number of the IGMP groups a port can join is reached.
Select Deny to drop any new IGMP join report received on this port until an existing multicast
forwarding table entry is aged out.
Select Replace to replace an existing entry in the multicast forwarding table with the new
IGMP reports received on this port.
IGMP Filtering Select the name of the IGMP filtering profile to use for this port. Otherwise, select Default to
Profile prohibit the port from joining any multicast group.
You can create IGMP filtering profiles in the Multicast > IPv4 Multicast > IGMP Snooping > IGMP
Filtering Profile screen.
IGMP Querier The Switch treats an IGMP query port as being connected to an IGMP multicast router (or
Mode server). The Switch forwards IGMP join or leave packets to an IGMP query port.
Select Auto to have the Switch use the port as an IGMP query port if the port receives IGMP
query packets.
Select Fixed to have the Switch always use the port as an IGMP query port. Select this when
you connect an IGMP multicast server to the port.
Select Edge to stop the Switch from using the port as an IGMP query port. The Switch will not
keep any record of an IGMP router being connected to this port. The Switch does not forward
IGMP join or leave packets to this port.
Chapter 24 Multicast
XMG1930 Series User's Guide
209