JAMBU Lightweight Authenticated Encryption Mode and AES-JAMBU

In this paper, we propose a lightweight authenticated encryption mode JAMBU. It only needs n-bit extra register for a block cipher with 2n-bit block size. It achieves n-bit authentication security when 2 bits are processed under a single key. When nonce (IV) is reused, the encryption security is similar to that of the CFB mode while the message authentication maintains strong security. We instantiate JAMBU with AES-128 as the underlying block cipher to construct an authenticated cipher AES-JAMBU. There are more lightweight authenticated ciphers can be constructed by applying JAMBU with lightweight block ciphers such as SIMON. To the best of our knowledge, JAMBU is the most lightweight authentication mode which provides n-bit authentication security.