Twin Clouds: Secure Cloud Computing with Low Latency

(Full Version)
  • Sven Bugiel
  • Stefan Nürnberger
  • Ahmad-Reza Sadeghi
  • Thomas Schneider
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7025)


Cloud computing promises a cost effective enabling technology to outsource storage and massively parallel computations. However, existing approaches for provably secure outsourcing of data and arbitrary computations are either based on tamper-proof hardware or fully homomorphic encryption. The former approaches are not scaleable, while the latter ones are currently not efficient enough to be used in practice.

We propose an architecture and protocols that accumulate slow secure computations over time and provide the possibility to query them in parallel on demand by leveraging the benefits of cloud computing. In our approach, the user communicates with a resource-constrained Trusted Cloud (either a private cloud or built from multiple secure hardware modules) which encrypts algorithms and data to be stored and later on queried in the powerful but untrusted Commodity Cloud. We split our protocols such that the Trusted Cloud performs security-critical precomputations in the setup phase, while the Commodity Cloud computes the time-critical query in parallel under encryption in the query phase.


Secure Cloud Computing Cryptographic Protocols Verifiable Outsourcing Secure Computation 


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Copyright information

© IFIP International Federation for Information Processing 2011

Authors and Affiliations

  • Sven Bugiel
    • 1
  • Stefan Nürnberger
    • 1
  • Ahmad-Reza Sadeghi
    • 1
  • Thomas Schneider
    • 1
  1. 1.Center for Advanced Security Research DarmstadtTechnische Universität DarmstadtGermany

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