This is the byte-volume counterpart to cktInODEFrames, showing exactly how many bytes of this circuit's optionally-discard-eligible traffic have arrived, which the admin uses alongside the frame counter to judge average frame size in that discard-priority tier. For example, a low octet count paired with a high frame count in this ODE class suggests the customer is marking many small control-type frames as optionally discardable rather than bulk data.