This is the per-entry hit counter for the extended ACL table, the same concept as cienaCesAclEntryHits in the base ACL table but scoped to this MIB's extended entries, which per the notification objects above appear to match on both source and destination criteria rather than source alone. An admin uses a zero or low hit count here similarly to the base table's version -- as a signal that a specific source-destination authorization pairing may be stale and worth pruning -- but the extended nature of the match makes a hit here a stronger confirmation that a specific, narrower flow is actually in active use. For example, an extended entry authorizing a specific partner subnet to a specific internal server showing steady non-zero hits confirms that exact pairing is actively used and shouldn't be removed during a cleanup pass, unlike a base-table entry that only confirms the source address alone is active.