by Rex Buddenberg

Diana one-time pads, were fairly common usage in the USCG, but we avoided their use like the plague because they were very labour intensive.  They came in two variations,  resulting in an each end unit having to carry three pads.  Besides, use aboard ship, Diana pads were used in the Loran station that I commanded in 1980.

The pads were simply lists of random characters (all uppercase alpha, no numbers), if I recall, in 5-letter groups.  I had a point-receive pad; my boss had the matching point-send pad.  I also had the converse - a point-send pad that matched the boss'.  Finally, we had a group-receive pad that was identical at all the Loran stations and the boss had the group-send pad.

The physical packaging was simply a stack of pages gummed together with a cover (with instructions printed on it) and a translation/garble sheet.

If you received a Diana-coded message, the opening code group told you which page you were to go to (all previous pages could be assumed to have been used and were to be destroyed).  Then you wrote the encrypted text under the random letters in the pad, and broke each letter pair with the translation sheet.  Numbers were spelled out (e.g. thirty five).

 Back to Menu Page
May 20/02