What is the number of rounds used in Camellia encryption?

Camellia encryption is designed to provide a high level of security while being efficient in terms of performance. The number of rounds used in the encryption process is a critical factor affecting the algorithm's strength and resistance to various types of cryptographic attacks.

In the case of Camellia, the correct answer indicates that it employs either 18 or 24 rounds depending on the key length used in the encryption process. Specifically, for a 128-bit key, Camellia uses 18 rounds, while for 192-bit and 256-bit keys, it utilizes 24 rounds. This structure enhances the algorithm's security by providing enough computational complexity to thwart most cryptanalytic attacks.

The variations in the number of rounds based on key length highlights Camellia's adaptability to different security requirements while maintaining efficiency, making it suitable for a broad range of applications. Understanding the rationale behind the selection of 18 or 24 rounds is crucial for recognizing how the algorithm balances security and performance.