Sunday, July 11, 2010


Sparks asked about the difference between DSA and RSA keys for SSH authentication.  Following is from a collection of notes over the years.  My sources have faded so you may want to do your own research if you planning on quoting any of the following:

  • DSA generates keys faster, but verifies them slower,  than RSA

  • DSA supposedly scales better

  • DSA doesn't have the license restrictions that RSA has

  • SSH protocol 1 only supports RSA

  • SSH protocol 2 supports both RSA and DSA, though many implementations only include DSA support for protocol 2

Hope this answers your question, Sparks.


  1. Actually, I wasn't specifically asking about SSH. I'm actually more interested in general data signing and encryption. And let's throw ElGamal and anything else we can think about and do a comparison.

  2. Will gen a list (table?) up...