[j-nsp] IGMP Join Rate Limiting

[Judah Scott]

When testing IGMP join rates I see an unusual rate of ~500pps.  In an
example I look at interface stats and see 1000 packets in, 539 input to
local, 461 input to transit.  Corresponding to this I see 539 IGMP groups
setup.  If I burst the same range again in the next second I don't learn any
more.  If I burst a new range of joins then these will go through.

This leads me to believe that there is some filter or DOS protection for
multicast packets because looking at the CPU I only see ~10% utilization.  I
only see the default arp l2-policer being applied on this interface.  Does
anyone have experience with DOS protection in JUNOS?


Thanks,
J Scott