Which algorithm uses a sponge construction and is designed to complement the SHA-2 family?

Which algorithm uses a sponge construction and is designed to complement the SHA-2 family?

• A. SHA-2
• B. SHA-3
• C. MD5
• D. RC6

Answer: (B)

SHA-3 is built on a sponge construction, where input is absorbed into a large internal state and then output is squeezed out, allowing for flexible output lengths. This approach comes from the Keccak design, which uses a permutation core and a different structure than the Merkle-Damgård scheme used by SHA-2. Because it leverages a distinct mechanism, SHA-3 is intended to complement the SHA-2 family, providing an alternative design with different security properties and resilience against certain attack vectors. The other options don’t fit: SHA-2 relies on Merkle-Damgård, MD5 is an older, compromised hash, and RC6 is a symmetric encryption algorithm, not a hash function.

SHA-3 is built on a sponge construction, where input is absorbed into a large internal state and then output is squeezed out, allowing for flexible output lengths. This approach comes from the Keccak design, which uses a permutation core and a different structure than the Merkle-Damgård scheme used by SHA-2. Because it leverages a distinct mechanism, SHA-3 is intended to complement the SHA-2 family, providing an alternative design with different security properties and resilience against certain attack vectors. The other options don’t fit: SHA-2 relies on Merkle-Damgård, MD5 is an older, compromised hash, and RC6 is a symmetric encryption algorithm, not a hash function.