What key lengths are supported by the AES encryption algorithm?

What key lengths are supported by the AES encryption algorithm?

• A. 128, 192, and 256 bits.
• B. 64, 128, 256 bits.
• C. 256, 512, and 1024 bits.
• D. 32, 64, 128 bits.

Answer: (A)

AES uses three defined key lengths to create its variants: 128, 192, and 256 bits. These correspond to AES-128, AES-192, and AES-256, offering different levels of security and performance. Longer keys mean more possible keys and thus stronger protection against brute-force attacks, with a trade-off in some cases of speed and resource use. The other options mix in key sizes that AES does not use (such as 64-bit keys or very large 512/1024-bit keys, or 32/64), so they don’t match how AES is defined.

AES uses three defined key lengths to create its variants: 128, 192, and 256 bits. These correspond to AES-128, AES-192, and AES-256, offering different levels of security and performance. Longer keys mean more possible keys and thus stronger protection against brute-force attacks, with a trade-off in some cases of speed and resource use. The other options mix in key sizes that AES does not use (such as 64-bit keys or very large 512/1024-bit keys, or 32/64), so they don’t match how AES is defined.