DSA (Digital Signature Algorithm) is a public-key signature algorithm defined by NIST.


RSA is a common public key algorithm, which can be used for encryption and signature

Verification 10x testing

Quality Example

"This is why rsa is much slower than dsa"

from question "What is DSA complexity?"

"However dsa verification expect verification calls to be 100x issue is about 10x slower than rsa verification"

from question "Public key signing algorithm"

"I have made some testing and it came out that rsa is lot slower than dsa"

from question "What is DSA complexity?"


Quality Example

"Dsa has signature that is independent of key strength and is much smaller than rsa signature for equivalent security rsa 1024 1568 vs dsa 192"

from question "Public key signing algorithm"


"However in this case dsa key size is less than rsa key size"

from question "Encrypt a DSA private key with RSA public key"


"A dsa signature generation could be somewhat faster than a rsa signature generation maybe up to twice faster"

from question "What's the most computationally expensive step in a SSH2 session?"

Better choice

"Rsa is also a better choice than dsa because it has much better breadth of support for signatures still considered secure by nist"

from question "Get SHA1 sign of string with DSA private key from PEM file"


"Dsa signatures are signficantly shorter than rsa ones"

from question "Generating short license keys with OpenSSL"

Keys much riskier

"That continued usage of 1024-bit prime field elgamal or dsa keys is much riskier than it is for 1024-bit rsa all are still commonly used because once a successful attack has been conducted against a single well-chosen prime field all users of that prime field may be affected at little additional effort."

from question "How to choose prime for implementing Diffie-hellman key exchange"


"I guess rsa is older and dsa is newer"

from question "Ssh host key verification failed on one of the clients only"

More compact

"Use dsa it tends to be more compact than rsa"

from question "Generate reasonable length license key with asymmetric encryption?"

Back to Home
Data comes from Stack Exchange with CC-BY-SA-3.0