Describes a set of dynamic service flow statistics. Two entries exist for each Docsis mac layer interface for the upstream and downstream direction. On the CMTS, the downstream direction row indicates messages transmitted or transactions originated by the CMTS. The upstream direction row indicates messages received or transaction originated by the CM. On the CM, the downstream direction row indicates messages received or transactions originated by the CMTS. The upstream direction row indicates messages transmitted by the CM or transactions originated by the CM. The ifIndex is an ifType of docsCableMaclayer(127).