When Pow Is Good

In cryptography we deal with large numbers … in fact very large numbers. While are processors have registers that hold 64 bits, and our integer values in programs are stored as 64-bit values, in crypto land these values are normally constrained only by the length of a large prime number. And, for example, if we operate on two 64-bit values, the result will be 128 bits in length, and we do not allow it to overflow (as we would in our normal operations).