SSH supports two signature algorithms for key pairs: RSA and DSA. Which is preferred, if any? For RSA, what is the minimum acceptable key length?
RSA is generally preferred (now that the patent issue is over with) because it can go up to 4096 bits, where DSA has to be exactly 1024 bits (in the opinion of
ssh-keygen). 2048 bits is
ssh-keygen's default length for RSA keys, and I don't see any particular reason to use shorter ones. (The minimum possible is 768 bits; whether that's "acceptable" is situational, I suppose.)