Comtech EF Data SLM-5650A - Manual (Page 205)

SLM-5650A Satellite Modem Revision 8
Network Processor (NP) Interface MN-SLM5650A
8–43
8.6.6.6.3 Routing | IGMP
Use this page to facilitate use of Internet Group Management Protocol (IGMP) with configured
multicast routes.
Figure 8-28. Routing | IGMP page
IGMP, when enabled, responds to IGMP queries for the configured multicast routes on the
transmit side and generates IGMP queries on the receive side. If there are no active IGMP
receivers on the LAN, it will stop forwarding the multicast traffic (received from the satellite) to
the LAN.
Selection Description / Setting
IGMP Select IGMP as Enabled or Disabled.
Query Interval
This is the interval between general queries sent by the modem. By varying the query
interval, a modem administrator may tune the number of IGMP messages on the subnet;
note that larger numbers cause the IGMP queries to be sent less often.
Enter a value, in seconds, from 1 to 60 (default = 1 second).
Response Interval
This is the maximum response time inserted into the periodic general queries. By
varying the Response Interval, a modem administrator may tune the “burstiness” of
IGMP messages on the subnet; note that larger values make the traffic less “bursty” as
host responses are spread out over a large interval.
Enter a value, in seconds, from 1 to 25 (default = 10 seconds).
Note: The number of seconds assigned to the Response Interval must be less than
what is assigned to the Query Interval.
Last Member Query
Interval
This is the maximum response time inserted into group-specific queries that are set in
response to Leave Group messages, and is also amount of time between group-
specific query messages. This value may be tuned to modify the "leave latency" of the
network; a reduced value results in reduced time to detect the loss of the last member
of a group.
Enter a value, in seconds, from 1 to 25 (default = 1 second).