Modern Block Cipher Intermediate
AES Modes of Operation: CTR, CFB, OFB, and XTS
AES only encrypts one 16-byte block. A mode of operation is the wrapper that turns that single block into something that protects a whole message or an entire disk. This guide walks through four modes, CTR, CFB, OFB, and XTS, with verified NIST numbers you can check yourself.
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