Abstract
Big Data applications are characterized by processing an amount of data too huge to be stored. Cryptographic protocols are by construction supposed to define huge data spaces that cannot be handled by any attacker. Nevertheless, the task of protocol cryptanalysis is to properly select cryptographic parameter lengths that guarantee both efficiency and security. This requires to break cryptographic protocols and their underlying hardness assumptions for mid-sized parameters. But even for mid-sized parameters cryptographic search spaces are way too huge to be stored. This asks for technical solutions that traverse the search space without storing elements. As an appealingly simple example, we address the subset sum problem which lies at the heart of many modern cryptographic protocols designed to offer security even against quantum computers. In the subset sum problem, one obtains integers
Funding statement: This work was funded by DFG under Germany’s Excellence Strategy - EXC 2092 CASA - 390781972.
About the author
Studied Computer Science at Frankfurt University (Diplom 1999). He did his PhD under the supervision of Johannes Blömer at ETH Zürich and Paderborn University (Promotion 2003). In 2005, he became Juniorprofessor at TU Darmstadt. Since 2007, he is Chair for Cryptology and IT Security at Ruhr-University Bochum. Currently, he is member of the DFG-Cluster of Excellence CASA – Cyber Security in the Age of Large-Scale Adversaries.
Acknowledgment
The author wants to thank the anonymous reviewers for their constructive comments.
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