Tightness of the Security Bound of CENC
نویسنده
چکیده
CENC (Cipher-based ENCryption) is the recently designed encryption mode for blockciphers. It is provably secure with beyond the birthday bound. In this note, we present a simple distinguishing attack on CENC, and show that the attack is the best attack for some parameter. This proves the tightness of the security bound, and gives a partial answer to the open question posed at FSE 2006.
منابع مشابه
New Blockcipher Modes of Operation with Beyond the Birthday Bound Security
In this paper, we define and analyze a new blockcipher mode of operation for encryption, CENC, which stands for Cipher-based ENCryption. CENC has the following advantages: (1) beyond the birthday bound security, (2) security proofs with the standard PRP assumption, (3) highly efficient, (4) single blockcipher key, (5) fully parallelizable, (6) allows precomputation of keystream, and (7) allows ...
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