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Recently NSA published two new algorithms, Simon and Speck. In the abstract they say

The aim of SIMON and SPECK is to fill the need for secure, flexible, and analyzable lightweight block ciphers.

so as the question title says, what does 'analyzable' mean? BTW I found the publication through Schneier's blog post about it.

I haven't had time to read the entire document but haven't found any other references to that particular word. Do they mean the algorithms are easy to be 'proven secure'? Or is it something else? To conclude, this question does invite some degree of discussion, if you feel it doesn't comply with the site's policy, please flag it down. Cheers

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The algorithms are similar to existing blockciphers, so cryptographers know how to analyze them. Being easy to analyze them is a good thing, because it becomes less likely that somebody suddenly find a new and much better attack. – CodesInChaos Jul 1 '13 at 13:53
Later on, they state: But the fact of the matter is that our algorithms have simple round functions that invite analysis, and we are hopeful that this will entice the cryptographic community to expend some e ffort studying them. This is probably an explanation of their meaning. – minar Jul 1 '13 at 17:24
up vote 9 down vote accepted

Analyzable in this case means "simple to study".

If your cipher consists of a small function that mixes a few things together, and then you repeat that often then your cipher is more easily understood and more easily fit into previous research knowledge than a overclomplicated large design. This is the case with Simon and Speck.

Being easy to analyze is a good property for a strong cipher. If people fully understand it and fully checked everything and still couldn't find a weakness then it adds confidence in the cipher. A more complicated design is more likely to have a "hidden weakness" - because more things can go wrong.

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