AMX NXA-ENET8-2POE Operation/Reference Manual page 112

Configuring the NXA-ENET8-2POE
IGMP Snooping Configuration parameters (Cont.)
Global Configuration
• Leave Proxy
Enabled
• Proxy Enabled
Port Related Configuration
• Port
• Router Port
• Fast Leave
102
Suppresses leave messages unless received from the last member port in the
group. (Default: Disabled) IGMP leave proxy suppresses all unnecessary IGMP
leave messages so that a non-querier switch forwards an IGMP leave packet only
when the last dynamic member port leaves a multicast group.
The leave-proxy feature does not function when a switch is set as the querier.
When the switch is a non-querier, the receiving port is not the last dynamic mem-
ber port in the group, the receiving port is not a router port, and no IGMPv1 mem-
ber port exists in the group, the switch will generate and send a group-specific
(GS) query to the member port which received the leave message, and then start
the last member query timer for that port.
When the conditions in the preceding item all apply, except that the receiving port
is a router port, then the switch will not send a GS-query, but will immediately start
the last member query timer for that port. Leave proxy is also included in the gen-
eral proxy function described below.
Therefore if Leave Proxy Enabled is not selected, but Proxy Enabled is selected,
leave proxy will still be performed.
Enables IGMP Snooping with Proxy Reporting. (Default: Disabled)
When proxy reporting is enabled with this command, the switch performs IGMP
Snooping with Proxy Reporting (as defined in DSL Forum TR-101, April 2006),
including report suppression, last leave, and query suppression.
Report suppression intercepts, absorbs and summarizes IGMP reports coming
from downstream hosts. Last leave sends out a proxy query when the last mem-
ber leaves a multicast group, and query suppression means that neither specific
queries nor general queries are forwarded from an upstream multicast router to
hosts downstream from this device.
When proxy reporting is disabled, all IGMP reports received by the switch are for-
warded natively to the upstream multicast routers.
Port identifier.
Sets a port to function as a router port, which leads towards a Layer 3 multicast
device or IGMP querier. (Default: Disabled) If IGMP snooping cannot locate the
IGMP querier, you can manually designate a port which is connected to a known
IGMP querier (i.e., a multicast router/switch). This interface will then join all the
current multicast groups supported by the attached router/switch to ensure that
multicast traffic is passed to all appropriate interfaces within the switch.
Immediately deletes a member port of a multicast service if a leave packet is
received at that port. (Default: Disabled) The switch can be configured to immedi-
ately delete a member port of a multicast service if a leave packet is received at
that port and the Fast Leave function is enabled. This allows the switch to remove
a port from the multicast forwarding table without first having to send an IGMP
group-specific (GS) query to that interface.
If Fast Leave is not used, a multicast router (or querier) will send a GS-query mes-
sage when an IGMPv2/v3 group leave message is received. The router/querier
stops forwarding traffic for that group only if no host replies to the query within the
specified timeout period. If Fast Leave is enabled, the switch assumes that only
one host is connected to the interface. Therefore, Fast Leave should only be
enabled on an interface if it is connected to only one IGMP-enabled device, either
a service host or a neighbor running IGMP snooping.
Fast Leave is only effective if IGMP snooping is enabled, and IGMPv2 or IGMPv3
snooping is used.
Fast Leave does not apply to a port if the switch has learned that a multicast
router is attached to it.
Fast Leave can improve bandwidth usage for a network which frequently experi-
ences many IGMP host add and leave requests.
NXA-ENET8-2POE Gigabit Ethernet Layer 2 PoE Switch