Please tell me how to achieve 1024 bit and above Arithmetic operation using 8, 16, 32 bit microcontroller. The Arithmetic operation consist of Addition, Subtraction, Multiplication, Division, Modulo.
1024 bit arithmetic is used in RSA and other crtyptography algorithms.
RSA is a public-key algorithm and uses so big numbers just to make it hard to factor the product of two very big primes and get back the primes.
Anyway - it is really trivial to implement arbitrary precision arithmetic just as long as the processor has enough RAM to store the numbers and any intermediary results.