TSEC-
Most U.S. government-approved communications security equipment has designations in the form TSEC/KG-99, in which TSEC/ (note slash) is purely an identification for a designation system, not an abbreviation. It complements the AN- system used for general military electronics, which does reserve certain of the letters in the AN/ system are reserved for NSA use.
While the designation system codes are quite complex and still contain special cases, the basic structure is:
- First letter: What is its function?
- Second letter: What information or physical materials does it process?
- Optional third letter: What kind of component is it?
The next numbers indicate a main model number within the series, followed by a bewildering and inconsistent set of version levels, alternate configurations, etc. Sometimes, what may seem an incremental improvement gets an entirely new model number, while a radical change may get a version change only. In other words, grasp the general principles of the system, but know that you will have to examine a specific system to understand its designation nuances.
- TSEC/KG-13 is a cryptographic key generator (code name PONTUS)
- TSEC/KY-57 was a cryptographic speech encryptor (code name VINSON)
- TSEC/KW-7 was a cryptographic key encryptor for asynchronous character data (i.e., "Teletype") (code name ORESTES)
Designation system codes
| Letter | Function | Type | Assembly |
|---|---|---|---|
| A | - | - | - |
| B | - | - | - |
| C | COMSEC equipment | - | - |
| D | - | - | - |
| E | - | - | - |
| F | - | - | - |
| G | General purpose | Key generation | - |
| H | Cryptographic ancillary | - | - |
| I | - | Data transmission | - |
| J | - | - | - |
| K | Cryptographic | - | - |
| L | - | Literal conversion | - |
| M | Manufacturing | - | - |
| N | Non-cryptographic | Signal conversion | - |
| O | - | Multipurpose | - |
| P | - | Materials Production | - |
| Q | - | - | - |
| R | - | - | - |
| S | Special purpose | Special purpose | - |
| T | - | Testing, checking, maintenance | - |
| U | - | Television | - |
| V | - | - | - |
| W | - | Teletypewriter | - |
| X | - | Facsimile | - |
| Y | - | Speech (ciphony) | - |
| Z | - | - |