Certified Information Systems Security Professional (CISSP) Practice Exam 2026 – All-in-One Guide to Mastering Your Certification!

The correct choice is Blowfish, a block cipher known for its flexible key length, which can vary between 32 bits and 448 bits. This adaptability is particularly beneficial in scenarios where stronger encryption is required, allowing users to select a key size that matches their specific security needs without being limited to a fixed key length.

Blowfish employs a Feistel network structure, making it both efficient and fast for applications requiring encryption and decryption. The larger key sizes provide enhanced security against brute-force attacks, which is crucial in protecting sensitive data in various computing environments. Blowfish's design allows it to be implemented in many algorithms and is popular in applications where speed and security are both critical factors.

While other block ciphers like DES, AES, and Twofish have their unique characteristics and key lengths, they do not share the same flexibility that Blowfish offers in terms of key size. DES, for example, uses a fixed key length of 56 bits, while AES specifically employs key lengths of 128, 192, or 256 bits, leaving it unable to cater to the wide range specified in the question. Twofish, while more flexible than DES, also has a fixed key length of 128, 192, or 256 bits