| Item | Description |
| AlignmentErrors | non-integral # of octets |
| FCSErrors | FCS error |
| IMacTransmitError | internal MAC layer error |
| IMacReceiveError | internal MAC layer error |
| CarrierSenseError | CSE problem |
| FrameTooLong | > 1518 octets |
| SQETestError | signal quality error |
| DeferredTransmiss | delay due to media busy |
| SingleCollFrames | one collision |
| MultipleCollFrames | multiple collision |
| LateCollisions | detect after 64 octets |
| ExcessiveCollis | excessive collisions |