### Modelling Time, or A Step Towards Reduction-based Security Proofs for OTP and Kerberos

Jörg Schwenk

##### Abstract

The notion of time plays an important role in many practically deployed cryptographic protocols, ranging from One-Time-Password (OTP) tokens to the Kerberos protocol. However, time is difficult to model in a Turing machine environment. We propose the first such model, where time is modelled as a global counter T . We argue that this model closely matches several implementations of time in computer environments. The usefulness of the model is shown by giving complexity-theoretic security proofs for OTP protocols, HMQV-like one-round AKE protocols, and a variant of the basic Kerberos building block.

##### Metadata
Available format(s)
Category
Cryptographic protocols
Publication info
Preprint. MINOR revision.
Keywords
BR modeltimestampOTPone-round AKEKerberos
Contact author(s)
joerg schwenk @ rub de
History
2013-09-23: received
Short URL
https://ia.cr/2013/604
License

CC BY

BibTeX

@misc{cryptoeprint:2013/604,
author = {Jörg Schwenk},
title = {Modelling Time, or A Step Towards Reduction-based Security Proofs for OTP and Kerberos},
howpublished = {Cryptology ePrint Archive, Paper 2013/604},
year = {2013},
note = {\url{https://eprint.iacr.org/2013/604}},
url = {https://eprint.iacr.org/2013/604}
}

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