Musobaqa DSA

The DSA (Digital Signature Algorithm) approach involves using of a hash function to create a hash code, same as RSA. This hash code is combined with a randomly generated number k as an input to a signature function. The signature function depends on the sender private key (PR_a) as well as a set of parameters that are known to a group of communicating principals. This set can be considered as a global public key (PU_G). The output of the signature function is a signature with two components, s and r. When an incoming message is received, a hash code is generated for the message. This hash code is then combined with the signature and input into a verification function. The verification function depends on the global public key as well as the sender's public key (PU_a) which is paired with the sender's private key. The output of the verification function returns a value equal to the signature's component r, if the signature is valid. The signature function is designed in such a way that only the sender, with knowledge of the private key, can produce a valid signature.