@inproceedings{8f5202ebde2b4807a3a8a29e2e5c85b4,
title = "Counter Mode for Long Messages and a Long Nonce",
abstract = "This paper proposes “Compound-CTR” mode—a simple variation of Counter mode (CTR) with an n bits block cipher. Its goal is to increase the allowed length of a single message and the total number of messages that can be encrypted under a single key. Compound-CTR encrypts a message and a (randomly chosen) nonce with length greater or equal n bits. It uses a master key to derive a nonce-based encryption key and subsequently uses it for encrypting the message in CTR mode. We show how Compound-CTR mode achieves its goal and explain why it can be used as a valid variation of CTR mode that could be of interest in some practical scenarios. Compared to CTR mode, the overhead of Compound-CTR is only the per-message key derivation and one extra key expansion (for the block cipher). We show here key derivation options that require only a few extra block cipher calls.",
keywords = "Block ciphers, Counter mode, Modes of operation",
author = "Shay Gueron",
note = "Publisher Copyright: {\textcopyright} 2022, Springer Nature Switzerland AG.; 6th International Symposium on Cyber Security Cryptography and Machine Learning, CSCML 2022 ; Conference date: 30-06-2022 Through 01-07-2022",
year = "2022",
doi = "10.1007/978-3-031-07689-3\_17",
language = "American English",
isbn = "9783031076886",
series = "Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)",
publisher = "Springer Science and Business Media Deutschland GmbH",
pages = "224--231",
editor = "Shlomi Dolev and Amnon Meisels and Jonathan Katz",
booktitle = "Cyber Security, Cryptology, and Machine Learning - 6th International Symposium, CSCML 2022, Proceedings",
address = "Germany",
}