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U.S. Army Guide to Code Breaking
sebFlyte writes "From the introduction of this document, the U.S. Army's field manual guide to Cryptanalysis: 'This manual presents the basic principles and techniques of cryptanalysts and their relation to cryptography. Cryptanalytics is the art and science of solving unknown codes and ciphers.'"
This document is also 15 years old. Let's think about computing power available 15 years ago. Yes, there were computers more than powerful enough to do handle brute force decryption, not to mention more sophisiticated means. In terms of portability, however, there was nothing. Computing power has become so inexpensive and widespread now that more advanced forms of cryptography have (natrually) replaced the older, hand driven cyphers of old. Let's also think about the types of encryption that were being used back then. The mathematics that it takes to drive many of these algorithms was simply not practical in 1990. This document is serves more as a historical artifact now rather than a practial guide to decrypting like the government.
Above and beyond that is gravy - if some soldier who's MOS is not codebreaking wants to try when he isn't doing his MOS, great.
www.eFax.com are spammers
Because few people bother to use them properly. The Confederacy had access to ciphers (Vigere) which were practically unbreakable at the time, but they didn't use them, and so it was well worth the North having codebreakers as they got some pretty useful intel from them. Similarly, although J. Terrorist could use PGP and be safe, he could just as easily be using Vigere or something weaker, so codebreaking certainly has its place.
I am trolling
But seriously, what happens when, out in the field, your equipment is broken. or stolen. or there weren't enough to go around. or you're captured and held as a POW, and the escape plan is encrypted and scratched into a tree behind a chunk of bark? bet you'll wish you read that manual then.
Case sensitive +1 shift on 1337 translation of Engrish text, punctuation/spacing excluded.
0) Cypertext: "B22 z1vs cb64 S c4m107 3 vt!!!"
1) Intermediate 1337: "A11 y0ur ba53 R b3l0ng 2 us!!!" --NB, "A11" not "All" as previous translators have given.
2) Engrish Plaintext: "All your base are belong to us!!!"
55 47 55 2e 20 55 4e 41 51 2e
//Information does not want to be free; it wants to breed.
This is the manual I used when I trained as a 98C (Signals Intelligence Analyst = SigInt) some 10 years ago. This is *still used* now.
:).
FOUO classification means it shouldn't have been published at all. Just because it's common knowledge does NOT declassify a document. The document can only be declassified by the originating authority (the people who wrote it, and classified it to begin with). You'll see "DECL:OADR" on these docs a lot - "Declassify on Originating Authority Directive".
This FM is meant to teach the basics of cryptology to ASVAB-passing recruits. We run through the whole thing. Some very smart people go into Intel. Some pretty dumb ones do too
Everyone is expected to pass the final after this is taught, which consists of 4 days worth of simulated "traffic" being passed between target stations. We've reference books for traffic pattern types, run locational analysis, crack subsitution ciphers - it's romping good fun.
The encryption methods taught are still used in the field, though less and less thanks to the Internet, crypto-secured frequency-hopping radios, and whatnot, mostly for Meteo and Logistics.
Brings back some nostalgia, reading though this. I hope they don't get into too much trouble for posting it.
-AutoNiN