The Solitaire Encryption Algorithm (1999)

[nealrs]

https://www.schneier.com/solitaire.html

[thristian]

It's worth noting that despite Schneier's best efforts, the Solitaire algorithm may not be as cryptographically strong as he hoped:

http://www.ciphergoth.org/crypto/solitaire/

(there's also the potential problem that the NSA's supercomputers have grown a lot more powerful in the decade-and-a-half since Cryptonomicon was published)

[ahazred8ta → thristian]

Yes, but apparently it's good enough for short messages of a page or so. Its weakness only matters when an adversary has megabytes to work with.

[robbintt → ahazred8ta]

It is also reasonable to use abbreviations. This not only impacts letter frequency, it also speeds encryption and reduces the efficacy of a Dictionary style attack.

[srtjstjsj → thristian]

That shows some weakness, but of the sort "less bits of entropy than ideal", not "orders of magnitude more crackable"

[dllthomas → srtjstjsj]

If it's more than 6.65 bits of entropy, those are the same thing. There remains the question of whether it is sufficient orders of magnitude more crackable...

[i336_ → thristian]

Thanks for mentioning this. I was wondering if this was "too good to be true" in the technical sense :)

[i336_]

Is anyone aware of any newer hand ciphers that have been produced since 1999, especially those subjected to continuous, aggressive high-speed attack throughout their design?

[ademarre → i336_]

There's Handycipher[0] from 2014. I remember learning about it from Bruce's blog[1], but haven't a clue how secure it is.

[0] http://eprint.iacr.org/2014/257.pdf

[1] https://www.schneier.com/blog/archives/2014/04/a_new_pencil-...