Number Of ElGamal

If all the prime factors of p - 1 are relatively
small, lots of cryptographic attacks are possible. Generally, primes p such that p-1 has a big prime
factor are much better.









Note: k; r can be computed before the message is seen. In addition, you need a new k and r
every time you sign a message. Otherwise, it will not be secure.







Digital Signature Algorithm (DSA)