**18.310 Assignment 7: RSA Coding ****Due
Monday November 1 -- Wednesday November 3, 2004**

2. Find two 4 digit primes, p and q and consider the RSA code based in their product. Choose a value z relatively prime to (p-1)(q-1) and construct an encoder, which raises any 8 number less than p*q to power x mod N. Hint: choose p and q both to be under 3000 and you won’t have trouble with excel.

3. Set up a spreadsheet which does

gcd(A,B) = a*A + b*B

Use this spreadsheet to find the power you need
to raise a received message to, mod N in order to decode it (by using

4. Build a decoder spreadsheet that will decode your encoded message to give back the original message, and get it to work so it actually does so.