---
_id: '9011'
abstract:
- lang: eng
  text: "Distributed ledgers provide high availability and integrity, making them
    a key enabler for practical and secure computation of distributed workloads among
    mutually distrustful parties. Many practical applications also require strong
    confidentiality, however. This work enhances permissioned and permissionless blockchains
    with the ability to manage confidential data without forfeiting availability or
    decentralization. The proposed Calypso architecture addresses two orthogonal challenges
    confronting modern distributed ledgers: (a) enabling the auditable management
    of secrets and (b) protecting distributed computations against arbitrage attacks
    when their results depend on the ordering and secrecy of inputs.\r\n\r\nCalypso
    introduces on-chain secrets, a novel abstraction that enforces atomic deposition
    of an auditable trace whenever users access confidential data. Calypso provides
    user-controlled consent management that ensures revocation atomicity and accountable
    anonymity. To enable permissionless deployment, we introduce an incentive scheme
    and provide users with the option to select their preferred trustees. We evaluated
    our Calypso prototype with a confidential document-sharing application and a decentralized
    lottery. Our benchmarks show that transaction-processing latency increases linearly
    in terms of security (number of trustees) and is in the range of 0.2 to 8 seconds
    for 16 to 128 trustees."
acknowledgement: 'We thank Nicolas Gailly, Vincent Graf, Jean-Pierre Hubaux, Wouter
  Lueks, Massimo Marelli, Carmela Troncoso, Juan-Ramón Troncoso Pastoriza, Frédéric
  Pont, and Sandra Siby for their valuable feedback. This project was supported in
  part by the ETH domain under PHRT grant #2017−201, and by the AXA Research Fund,
  Byzgen, DFINITY, and the Swiss Data Science Center (SDSC).'
article_processing_charge: No
article_type: original
author:
- first_name: Eleftherios
  full_name: Kokoris Kogias, Eleftherios
  id: f5983044-d7ef-11ea-ac6d-fd1430a26d30
  last_name: Kokoris Kogias
- first_name: Enis Ceyhun
  full_name: Alp, Enis Ceyhun
  last_name: Alp
- first_name: Linus
  full_name: Gasser, Linus
  last_name: Gasser
- first_name: Philipp
  full_name: Jovanovic, Philipp
  last_name: Jovanovic
- first_name: Ewa
  full_name: Syta, Ewa
  last_name: Syta
- first_name: Bryan
  full_name: Ford, Bryan
  last_name: Ford
citation:
  ama: 'Kokoris Kogias E, Alp EC, Gasser L, Jovanovic P, Syta E, Ford B. CALYPSO:
    Private data management for decentralized ledgers. <i>Proceedings of the VLDB
    Endowment</i>. 2020;14(4):586-599. doi:<a href="https://doi.org/10.14778/3436905.3436917">10.14778/3436905.3436917</a>'
  apa: 'Kokoris Kogias, E., Alp, E. C., Gasser, L., Jovanovic, P., Syta, E., &#38;
    Ford, B. (2020). CALYPSO: Private data management for decentralized ledgers. <i>Proceedings
    of the VLDB Endowment</i>. Association for Computing Machinery. <a href="https://doi.org/10.14778/3436905.3436917">https://doi.org/10.14778/3436905.3436917</a>'
  chicago: 'Kokoris Kogias, Eleftherios, Enis Ceyhun Alp, Linus Gasser, Philipp Jovanovic,
    Ewa Syta, and Bryan Ford. “CALYPSO: Private Data Management for Decentralized
    Ledgers.” <i>Proceedings of the VLDB Endowment</i>. Association for Computing
    Machinery, 2020. <a href="https://doi.org/10.14778/3436905.3436917">https://doi.org/10.14778/3436905.3436917</a>.'
  ieee: 'E. Kokoris Kogias, E. C. Alp, L. Gasser, P. Jovanovic, E. Syta, and B. Ford,
    “CALYPSO: Private data management for decentralized ledgers,” <i>Proceedings of
    the VLDB Endowment</i>, vol. 14, no. 4. Association for Computing Machinery, pp.
    586–599, 2020.'
  ista: 'Kokoris Kogias E, Alp EC, Gasser L, Jovanovic P, Syta E, Ford B. 2020. CALYPSO:
    Private data management for decentralized ledgers. Proceedings of the VLDB Endowment.
    14(4), 586–599.'
  mla: 'Kokoris Kogias, Eleftherios, et al. “CALYPSO: Private Data Management for
    Decentralized Ledgers.” <i>Proceedings of the VLDB Endowment</i>, vol. 14, no.
    4, Association for Computing Machinery, 2020, pp. 586–99, doi:<a href="https://doi.org/10.14778/3436905.3436917">10.14778/3436905.3436917</a>.'
  short: E. Kokoris Kogias, E.C. Alp, L. Gasser, P. Jovanovic, E. Syta, B. Ford, Proceedings
    of the VLDB Endowment 14 (2020) 586–599.
corr_author: '1'
date_created: 2021-01-17T23:01:13Z
date_published: 2020-12-01T00:00:00Z
date_updated: 2024-10-09T21:00:32Z
day: '01'
department:
- _id: ElKo
doi: 10.14778/3436905.3436917
external_id:
  isi:
  - '000658495400012'
intvolume: '        14'
isi: 1
issue: '4'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://dl.acm.org/doi/10.14778/3436905.3436917
month: '12'
oa: 1
oa_version: Published Version
page: 586-599
publication: Proceedings of the VLDB Endowment
publication_identifier:
  eissn:
  - 2150-8097
publication_status: published
publisher: Association for Computing Machinery
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'CALYPSO: Private data management for decentralized ledgers'
tmp:
  image: /images/cc_by_nc_nd.png
  legal_code_url: https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode
  name: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
    (CC BY-NC-ND 4.0)
  short: CC BY-NC-ND (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 14
year: '2020'
...