DSA (Digital Signature Algorithm) is an Asymmetric encryption algorithm that is known for being fast at cryptographically signing but slow at verifying. Slow at encrypting but fast at decrypting.
RSA (named after its published creators Rivest, Shamir and Adleman) and is also an Asymmetric encryption algorithm.
To define the difference between Asymmetric and Symmetric encryption: Symmetric relies on a single private key mixed with secret input - you can use block or stream ciphers. Asymmetric uses a combination of a public and private keys and require fixed bit lengths such as 1024, 2048 etc. The public key is allowed to be distributed so long as the private key remains secure. The private key is used for digitally signing where the public key can be used to verify the integrity of that.
The encryption is done through the intended recipients public key and the creators private key, then the combination of the recipients private key and senders public key can decrypt it.
DSA is based on a discrete logarithmic problem. RSA is based on the difficulty in the factorization of large integers.
RSA is far more common and commercially accepted. While it is possible for DSA to be over 1024 bits, many applications limit it to this. As such 2048 RSA algorithms are widely accepted as the minimum security standard to be cryptographically secure.
I am not well aware of the technique behind digital signature but this article helped me to learn about this important aspect. All the points are clearly described. Thanks.
ReplyDeletedigital signature FAQ