Weak Consistency mode in Key Transparency: OPTIKS

Esha Ghosh; Melissa Chase

Paper 2024/796

Weak Consistency mode in Key Transparency: OPTIKS

Esha Ghosh

, Microsoft Research

Melissa Chase

, Microsoft Research

Abstract

The need for third-party auditors in privacy-preserving Key Transparency (KT) systems presents a deployment challenge. In this short note, we take a simple privacy-preserving KT system that provides strong security guarantees in the presence of an honest auditor (OPTIKS) and show how to add a auditor-free mode to it. The auditor-free mode offers slightly weaker security. We formalize this security property and prove that our proposed protocol satisfies our security definition.

Metadata

Available format(s): PDF
Category: Cryptographic protocols
Publication info: Preprint.
Keywords: Key Transparency Client Monitoring Checkpointing Zero Knowledge Set
Contact author(s): esha ghosh @ microsoft com
melissac @ microsoft com
History: 2024-05-24: approved; 2024-05-23: received; See all versions
Short URL: https://ia.cr/2024/796
License: CC BY

BibTeX

@misc{cryptoeprint:2024/796,
      author = {Esha Ghosh and Melissa Chase},
      title = {Weak Consistency mode in Key Transparency: {OPTIKS}},
      howpublished = {Cryptology {ePrint} Archive, Paper 2024/796},
      year = {2024},
      url = {https://eprint.iacr.org/2024/796}
}