Classical polygraphic substitution cipher using two 5x5 Polybius squares for digraph encryption with enhanced security.
| Property | Value |
|---|---|
| Category | Classical Ciphers |
| Sub-category | Polygraphic Cipher |
| Security status | 🎓 Educational Only |
| Complexity | Intermediate |
| Inventor | Unknown |
| Year | 1850 |
| Origin | ❓ Unknown |
| Source | algorithms/classical/twosquare.js |
Status: 🎓 Educational Only
No vulnerabilities are recorded for this implementation.
2 vectors ship with this algorithm and run in the test suite. Byte values are hexadecimal.
Vector 1 — Keywords SECRET and CIPHER, odd-length message padded with X. No published source carries this value
| Field | Value |
|---|---|
key |
5345435245542c434950484552 |
input |
48454c4c4f |
expected |
4d434b4d5057 |
Vector 2 — Keywords EXAMPLE and KEYWORD, J folded onto I. No published source carries this value
| Field | Value |
|---|---|
key |
4558414d504c452c4b4559574f5244 |
input |
41545441434b41544441574e |
expected |
455652434c59455643425650 |