4 ms·
What is DSA? I checked wiki and it looks like RSA for signatures, using modular exponentials. RSA is going to stay for a while, so why is DSA removed?
by charlieyu1 3y ago
What is DSA? I checked wiki and it looks like RSA for signatures, using modular exponentials. RSA is going to stay for a while, so why is DSA removed?
- skissane 3y agoDSA was an alternative to RSA developed by the NSA, which used (other parts of) the US government to push for its implementation. It was never entirely clear why they were doing that, and there have always been (unproven) suspicions that the NSA wanted it adopted over RSA for underhanded reasons. Due to this history, it was never anywhere near as popular as RSA. Anyway, the US government (NIST) now recommends use of DSA be discontinued. By contrast, RSA was developed in academia and its adoption was independent of the US government’s influence (and at times even against its preference for DSA instead)
- jepler 3y agoMy impression is that RSA was covered by patent (from 1983 until 2001). DSA was attractive in part because, while patented, the primary patent was held by the US government and royalty-free. I have vague memories (from circa 1995 comp sci undergrad coursework) that discrete log and integer factorization both appeared similarly difficult as mathematical/algorithmic problems. Thus, if you had to choose between a patent-encumbered protocol and a royalty-free one, it would make sense to choose DSA. That said, it seems to have never offered a particular advantage, and the modern view appears to be that DSA is weaker in practical terms.
- abraxis 3y agoRSA and DSA rely on different number theory problems. RSA relies on prime factorization being hard while DSA relies on the discrete logarithm being hard.