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ElGamal e-signature scheme.

COMPLETED.

This protocol is executed between Student Alice (You) and Mentor Bob. Parameter values sent by Alice are included in brackets [ ] and must be entered in the corresponding input fields.

The following functions are used in the protocol:

**>> genstrongprime(bl)**

**>> mod_exp(g,x,p)**

**>> randi(z)**

**>> H28(D)**

To compute H-function value ** h** for the message

1. Generate strong prime number ** p** of 28 bits length using Octave function

>> genstrongprime(28)

You could wait for a moment. You must check that generated ** p** is greater than 2^27= 134217728. Send [

2. If it is OK, find a generator ** g** of multiplicative group

3. If it is OK, generate at random secret number ** x** in the interval

4. Sign message containing current date and time in the format ** DT**=MMDDhhmm, by computing

5. Mentor’s Public Key is ** B**, where e.g.

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