Question about discrete logarithm problem
To convert every protocol based on DPL to ECDPL based protocol there is a limitation as EC uses generators from a very large prime(or binary) fields. For an instance consider ECDSA which is an EC analogy of DSA, in ECDSA there is a Generator G (used in calculating public key) is from a large prime subgroup of EC where as in DSA the private key (x) is just a random number such that  0 &lt; x &lt; q where q is N-bit prime number.