You are looking at a specific version 20180222:161528 of this paper. See the latest version.

Paper 2018/209

Hidden in Plain Sight: Storing and Managing Secrets on a Public Ledger

Eleftherios Kokoris-Kogias and Enis Ceyhun Alp and Sandra Deepthy Siby and Nicolas Gaillya and Philipp Jovanovic and Linus Gasser and Bryan Ford

Abstract

Current blockchain systems are incapable of holding sensitive data securely on their public ledger while supporting accountability of data access requests and revocability of data access rights. Instead, they either keep the sensitive data off-chain as a semi-centralized solution or they just publish the data on the ledger ignoring the problem altogether. In this work, we introduce SCARAB the first secure decentralized access control mechanism for blockchain systems that addresses the challenges of accountability, by publicly logging each request before granting data access, and of revocability, by introducing collectively managed data access policies. SCARAB introduces, therefore, on-chain secrets, which utilize verifiable secret sharing to enable collectively managed secrets under a Byzantine adversary, and identity skipchains, which enable the dynamic management of identities and of access control policies. The evaluation of our SCARAB implementation shows that the latency of a single read/write request scales linearly with the number of access-securing trustees and is in the range of 200 ms to 8 seconds for 16 to 128 trustees.

Metadata
Available format(s)
PDF
Category
Applications
Publication info
Preprint. MINOR revision.
Keywords
blockchaindecentralisationaccess controlkey managementthreshold cryptographyfair-exchange
Contact author(s)
eleftherios kokoriskogias @ epfl ch
History
2020-12-23: last of 6 revisions
2018-02-22: received
See all versions
Short URL
https://ia.cr/2018/209
License
Creative Commons Attribution
CC BY
Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content.