trial division is a type of integer

trial division is a type of integer factorization algorithm. it is the simplest algorithm to factor the modulus for breaking RSA cryptosystem. The modulus usually is trial divided by all possible odd integers which are less than the square root of the modulus. So, the initial odd integer for trial dividing the modulus is started by 3 and up to square root of the modulus. The disadvantage of TD is that, we must waste time to trial divide the modulus by some odd integers which are not primes, the factors of the modulus must be only primes.