| atp.bitmap | Bitmap | Unsigned 8-bit integer | Bitmap or sequence number |
| atp.ctrlinfo | Control info | Unsigned 8-bit integer | control info |
| atp.eom | EOM | Boolean | End-of-message |
| atp.fragment | ATP Fragment | No value | ATP Fragment |
| atp.fragments | ATP Fragments | No value | ATP Fragments |
| atp.function | Function | Unsigned 8-bit integer | function code |
| atp.segment.error | Desegmentation error | No value | Desegmentation error due to illegal segments |
| atp.segment.multipletails | Multiple tail segments found | Boolean | Several tails were found when desegmenting the packet |
| atp.segment.overlap | Segment overlap | Boolean | Segment overlaps with other segments |
| atp.segment.overlap.conflict | Conflicting data in seagment overlap | Boolean | Overlapping segments contained conflicting data |
| atp.segment.toolongsegment | Segment too long | Boolean | Segment contained data past end of packet |
| atp.sts | STS | Boolean | Send transaction status |
| atp.tid | TID | Unsigned 16-bit integer | Transaction id |
| atp.treltimer | TRel timer | Unsigned 8-bit integer | TRel timer |
| atp.user_bytes | User bytes | Unsigned 32-bit integer | User bytes |
| atp.xo | XO | Boolean | Exactly-once flag |