ACC-MIB::accIpxRtCost tracks the cumulative cost metric to reach the destination network as a read-only integer, used to choose the best route when multiple paths exist. Network engineers compare cost values across routes to ensure the router is using the most efficient path and to detect when link quality degrades. For example, a cost of 7 is better (lower) than a cost of 15 to the same destination, so the router would prefer the path with cost 7.