Ip is a read-only Counter32 giving the number of Internet Protocol (IP) frames counted for the monitored network; per the MIB a value of 4294967294 means the count is unknown rather than genuinely zero. Because it is broken out on its own instead of folded into a generic IP total, an admin can watch this counter to see how much of the monitored network's traffic is general IP-layer traffic not broken out into one of the other named protocol buckets. If this Ip counter climbs sharply on the segment this probe watches while total traffic stays flat, that shift shows general IP-layer traffic not broken out into one of the other named protocol buckets is displacing whatever other protocol mix was there before.