May 23rd, 2007

with Cat The Cat

Забавное про стеганографию.

со слешдота. Цитата, практически полная:
I was working in Eastern Europe on a now unclassified project, working against a low budget illegal foreign intelligence agency. They were selling and distributing porn CD's and DVD's with thousands of pictures, one or more of which would contain an encrypted stenographic message. Their contact would purchase the DVD at one of hundreds of little markets, and decrypt the proper image(s).

It was really quite a good plan. Not only were there many possible valid messages to one or more agents, but there were also an unknown number of false messages, they even may have even been all false messages that could only be put together by inference. However, since they were encrypted with PGP, we never were able to break that particular system before I left the project.

The real genius of the plan was that it brought them in some much needed cash as well.
Голь на выдумки хитра. ;)
with Cat The Cat

Там же, рядом.

Про шифр Навахо, Тоже обширная цитата:
The reason Navajo Code Talkers were succesful wasn't because the scheme was particularly advanced. In fact, it would have been computationally trivial to break. However the messages relayed were only ever "tactical" in nature; i.e. communications in the field, of use during a fight, but old news in about 10 minutes. Had Navajo code talking been used to relay top-secret messages, it would have been broken fairly quickly. The reason for its success was that is was extremely cheap to implement for the US, and the secrets protected weren't valuable enough to spend huge effort on breaking. Economics, rather than mathematics.

Navajo wasn't used in Europe, because Germany had sent anthropologists to the US to learn native languages, anticipating precisely this scheme.