The value of the object sapIgmpSnpgCfgRobustCount specifies
the robustness variable on this SAP.
This object allows tuning for the expected packet loss on this SAP.
If a SAP is expected to be lossy, the Robustness Variable may be
increased. IGMP snooping is robust to (Robustness Variable-1) packet
losses.
The value of this object is only meaningful when the value of
sapIgmpSnpgCfgSendQueries is 'enabled(1)'.