RC2 uses how many rounds during encryption?

RC2 is a block cipher that was designed by Ronald Rivest in the late 1980s. For encryption, RC2 employs a variable number of rounds, which is dependent on the key size. The standard implementation of RC2 uses 18 rounds during the encryption process. This number of rounds contributes to the cipher's security level, as more rounds typically enhance resistance to various types of cryptographic attacks.

In RC2, each round involves a series of transformations and permutations applied to the data, which creates confusion and diffusion necessary for effective encryption. The design choice of 18 rounds strikes a balance between security and performance, ensuring that the algorithm is robust while still being efficient enough for practical use.

Thus, understanding that RC2 utilizes 18 rounds is fundamental when discussing its encryption process and effectiveness in secure communications. The other options suggest different round counts that do not correspond to the standard implementation details of RC2, further emphasizing that 18 rounds is the definitive answer.