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| | exam1sol.doc |
 | | In general, an affine encryption function with keys A and B, where A and B are integers in the set {0,1,2,...,25} takes the form e(x) = (Ax + B) mod 26. |
 | | Assuming that a=0, b=1,..., z=25, the following is an affine encryption function: e(x) = (7x + 12) mod 26 Find the corresponding decryption function d(x) of the form d(x) = (Cx + D) mod 26, where C and D are in the set {0, 1, 2,..., 25} for the encryption function given above. |
 | | Incidentally, 12 values from {0,1, 2,..., 25} are relatively prime to 26, so there are a possible 12x26 = 312 keys for the affine cipher. |
| longwood.cs.ucf.edu /~dmarino/ucf/cot5937/exam1sol.doc (1211 words) |
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