This read-only counter reports the highest 1-minute multicast packet rate, in packets per minute, observed on this port's inbound direction since tracking began or was last cleared. An admin watches this on ports carrying multicast video or routing-protocol traffic to catch abnormal multicast storms or bursts. For example, an unusually high portInMulticastPktsPeak on an access port that shouldn't be receiving multicast traffic could indicate a misconfigured device or a multicast loop.