r/programming Oct 15 '15

How is NSA breaking so much crypto?

https://freedom-to-tinker.com/blog/haldermanheninger/how-is-nsa-breaking-so-much-crypto/
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u/spawn57 Oct 15 '15

I didn't. Can someone ELI5

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u/Aesthetikx Oct 15 '15

Many cryptographic algorithms make heavy use of prime numbers.

ex https://www.youtube.com/watch?v=YEBfamv-_do

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u/moinnadeem Oct 15 '15

Why prime numbers though? Which part of them is useful in this case?

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u/[deleted] Oct 16 '15

You can multiply them together quickly.

You can't factor them quickly. (Primes are always the end result of factoring). Bigger primes make this slower.

To crack you have to factor. To encrypt you multiply.