Weakening the isolation assumption of tamper-proof hardware tokens

Rafael Dowsley, Jörn Müller-Quade, Tobias Nilges

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearchpeer-review

6 Citations (Scopus)


Recent results have shown the usefulness of tamper-proof hardware tokens as a setup assumption for building UC-secure two-party computation protocols, thus providing broad security guarantees and allowing the use of such protocols as buildings blocks in the modular design of complex cryptography protocols. All these works have in common that they assume the tokens to be completely isolated from their creator, but this is a strong assumption. In this work we investigate the feasibility of cryptographic protocols in the setting where the isolation of the hardware token is weakened. We consider two cases: (1) the token can relay messages to its creator, or (2) the creator can send messages to the token after it is sent to the receiver. We provide a detailed characterization for both settings, presenting both impossibilities and information-theoretically secure solutions.

Original languageEnglish
Title of host publicationInformation Theoretic Security
Subtitle of host publication8th International Conference, ICITS 2015 Lugano, Switzerland, May 2–5, 2015 Proceedings
EditorsAnja Lehmann, Stefan Wolf
Place of PublicationCham Switzerland
Number of pages17
ISBN (Electronic)9783319174709
ISBN (Print)9783319174693
Publication statusPublished - 2015
Externally publishedYes
Event8th International Conference on Information Theoretic Security, ICITS 2015 - Lugano, Switzerland
Duration: 2 May 20155 May 2015

Publication series

NameLecture Notes in Computer Science
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


Conference8th International Conference on Information Theoretic Security, ICITS 2015


  • Hardware Tokens
  • Isolation Assumption
  • Oblivious Transfer
  • One-Time Memory
  • UC security

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