A symmetric key encryption scheme is described for blocks of general size N that is a product of powers of many prime numbers. This is accomplished by realising each number (representing a message unit) as a point in a product of affine spaces over various finite fields. Then algebro-geometric transformations on those affine spaces is transported back to provide encryption. For a specific block size${ }<2^{ 128}$ we get more than $2^{ 5478}$ keys.
Categories: cs.CR math.AG math.NT