This object tunes the IGMP Robustness Variable for this interface, which allows the protocol to tolerate a certain number of lost packets on lossy subnets; IGMP is robust to (Robustness Variable minus 1) packet losses. Administrators increase this value on subnets known to have poor reliability to prevent premature timeout of legitimate group memberships. For example, an engineer managing a wireless multicast segment with frequent packet loss might raise this value above the default to reduce false membership expirations.