This cyclic counter tallies non-mac frames that included a routing information field (RIF) received by higher-level software on this interface; meaningful for token ring interfaces only. Admins use it to see how much traffic is source-route-bridged (carrying a RIF) versus locally-originated, useful when troubleshooting source-route bridging behavior on the ring. For example, an unexpectedly high count here on a ring that shouldn't see bridged traffic would flag an unwanted bridging path.