| sna.rh | Request/Response Header | No value |
| sna.rh.0 | Request/Response Header Byte 0 | Unsigned 8-bit integer |
| sna.rh.1 | Request/Response Header Byte 1 | Unsigned 8-bit integer |
| sna.rh.2 | Request/Response Header Byte 2 | Unsigned 8-bit integer |
| sna.rh.bbi | Begin Bracket Indicator | Boolean |
| sna.rh.bci | Begin Chain Indicator | Boolean |
| sna.rh.cdi | Change Direction Indicator | Boolean |
| sna.rh.cebi | Conditional End Bracket Indicator | Boolean |
| sna.rh.csi | Code Selection Indicator | Unsigned 8-bit integer |
| sna.rh.dr1 | Definite Response 1 Indicator | Boolean |
| sna.rh.dr2 | Definite Response 2 Indicator | Boolean |
| sna.rh.ebi | End Bracket Indicator | Boolean |
| sna.rh.eci | End Chain Indicator | Boolean |
| sna.rh.edi | Enciphered Data Indicator | Boolean |
| sna.rh.eri | Exception Response Indicator | Boolean |
| sna.rh.fi | Format Indicator | Boolean |
| sna.rh.lcci | Length-Checked Compression Indicator | Boolean |
| sna.rh.pdi | Padded Data Indicator | Boolean |
| sna.rh.pi | Pacing Indicator | Boolean |
| sna.rh.qri | Queued Response Indicator | Boolean |
| sna.rh.rlwi | Request Larger Window Indicator | Boolean |
| sna.rh.rri | Request/Response Indicator | Unsigned 8-bit integer |
| sna.rh.rti | Response Type Indicator | Boolean |
| sna.rh.ru_category | Request/Response Unit Category | Unsigned 8-bit integer |
| sna.rh.sdi | Sense Data Included | Boolean |
| sna.th | Transmission Header | No value |
| sna.th.0 | Transmission Header Byte 0 | Unsigned 8-bit integer |
| sna.th.cmd_fmt | Command Format | Unsigned 8-bit integer |
| sna.th.cmd_sn | Command Sequence Number | Unsigned 16-bit integer |
| sna.th.cmd_type | Command Type | Unsigned 8-bit integer |
| sna.th.daf | Destination Address Field | Unsigned 16-bit integer |
| sna.th.dcf | Data Count Field | Unsigned 16-bit integer |
| sna.th.def | Destination Element Field | Unsigned 16-bit integer |
| sna.th.dsaf | Destination Subarea Address Field | Unsigned 32-bit integer |
| sna.th.efi | Expedited Flow Indicator | Unsigned 8-bit integer |
| sna.th.er_vr_supp_ind | ER and VR Support Indicator | Unsigned 8-bit integer |
| sna.th.ern | Explicit Route Number | Unsigned 8-bit integer |
| sna.th.fid | Format Identifer | Unsigned 8-bit integer |
| sna.th.iern | Initial Explicit Route Number | Unsigned 8-bit integer |
| sna.th.lsid | Local Session Identification | Unsigned 8-bit integer |
| sna.th.mft | MPR FID4 Type | Boolean |
| sna.th.mpf | Mapping Field | Unsigned 8-bit integer |
| sna.th.nlp_cp | NLP Count or Padding | Unsigned 8-bit integer |
| sna.th.nlpoi | NLP Offset Indicator | Unsigned 8-bit integer |
| sna.th.ntwk_prty | Network Priority | Unsigned 8-bit integer |
| sna.th.oaf | Origin Address Field | Unsigned 16-bit integer |
| sna.th.odai | ODAI Assignment Indicator | Unsigned 8-bit integer |
| sna.th.oef | Origin Element Field | Unsigned 16-bit integer |
| sna.th.osaf | Origin Subarea Address Field | Unsigned 32-bit integer |
| sna.th.piubf | PIU Blocking Field | Unsigned 8-bit integer |
| sna.th.sa | Session Address | Byte array |
| sna.th.snai | SNA Indicator | Boolean |
| sna.th.snf | Sequence Number Field | Unsigned 16-bit integer |
| sna.th.tg_nonfifo_ind | Transmission Group Non-FIFO Indicator | Boolean |
| sna.th.tg_snf | Transmission Group Sequence Number Field | Unsigned 16-bit integer |
| sna.th.tg_sweep | Transmission Group Sweep | Unsigned 8-bit integer |
| sna.th.tgsf | Transmission Group Segmenting Field | Unsigned 8-bit integer |
| sna.th.tpf | Transmission Priority Field | Unsigned 8-bit integer |
| sna.th.vr_cwi | Virtual Route Change Window Indicator | Unsigned 16-bit integer |
| sna.th.vr_cwri | Virtual Route Change Window Reply Indicator | Unsigned 16-bit integer |
| sna.th.vr_pac_cnt_ind | Virtual Route Pacing Count Indicator | Unsigned 8-bit integer |
| sna.th.vr_rwi | Virtual Route Reset Window Indicator | Boolean |
| sna.th.vr_snf_send | Virtual Route Send Sequence Number Field | Unsigned 16-bit integer |
| sna.th.vr_sqti | Virtual Route Sequence and Type Indicator | Unsigned 16-bit integer |
| sna.th.vrn | Virtual Route Number | Unsigned 8-bit integer |
| sna.th.vrprq | Virtual Route Pacing Request | Boolean |
| sna.th.vrprs | Virtual Route Pacing Response | Boolean |