⁉️ Unknown Tag for Revision
General Information
This test validates MISB ST 0601 packets against the tag range allowed by the packet revision. It does not flag every unfamiliar tag individually. Instead, it compares the highest tag number present in the decoded packet with the highest tag number defined by the schema for that revision.
The revision is derived from Tag 65: UAS Datalink LS Version Number.
If Tag 65 is not present, the validator falls back to the base MISB ST 0601 revision.
Revision Limits
The validator resolves the highest allowed tag number from the MISB ST 0601 revision metadata for the detected revision.
MISB601 Revisions
| Revision | Highest defined tag |
|---|---|
| base | 143 |
| Revision 1 | 72 |
| Revision 2 | 73 |
| Revision 3 | 76 |
| Revision 4 | 80 |
| Revision 5 | 93 |
| Revision 6 | 94 |
| Revision 7 | 95 |
| Revision 8 | 95 |
| Revision 9 | 96 |
| Revision 10 | 102 |
| Revision 11 | 105 |
| Revision 12 | 108 |
| Revision 13 | 141 |
| Revision 14 | 141 |
| Revision 15 | 141 |
| Revision 16 | 141 |
| Revision 17 | 142 |
| Revision 18 | 142 |
| Revision 19 | 143 |
What This Test Does
The Unknown Tag for Revision test:
- decodes the packet into raw KLV items
- reads Tag 65 when present to determine the MISB ST 0601 revision
- resolves the highest valid tag number for that revision from the schema
- finds the highest tag number present in the packet
- fails when the highest observed tag exceeds the highest allowed tag for that revision
If Tag 65 contains an invalid value or an unsupported revision number, the validator reports that as an unknown-tag-for-revision failure as well.
✅ Pass Criteria
The test passes when every decoded MISB ST 0601 packet stays within the highest allowed tag number for its resolved revision.
❌ Fail Criteria
The test fails when:
- a packet contains a tag number above the highest allowed tag for its revision
- Tag 65 cannot be decoded as a valid version number
- Tag 65 specifies a revision the validator does not recognize
Example
A typical failure looks like:
unknown-tag-for-revision validation failed: Tag 73 exceeds the highest allowed tag 72 for revision rev1
The process result points to the first packet where the revision-specific tag limit was exceeded and reports the byte offset and packet index of that source packet.