Black-Box Models of Computation in Cryptology

Generic group algorithms solve computational problems defined over algebraic groups without exploiting properties of a particular representation of group elements. This is modeled by treating the group as a black-box. The fact that a computational problem cannot be solved by a reasonably restricted class of algorithms may be seen as support towards the conjecture that the problem is also hard in the classical Turing machine model. Moreover, a lower complexity bound for certain algorithms is a helpful insight for the search for cryptanalytic algorithms.

Tibor Jager addresses several fundamental questions concerning algebraic black-box models of computation: Are the generic group model and its variants a reasonable abstraction? What are the limitations of these models? Can we relax these models to bring them closer to the reality?

• Black-Box Models of Computation
• Computational Complexity
• Computational Number Theory and Algebra
• Cryptographic Hardness Assumptions
• Generic Group Model

• Velbert, Germany

  Tibor Jager

Dr. Tibor Jager completed his doctoral thesis at the Horst Görtz Institute for IT Security at Ruhr-Universität Bochum under the supervision of Prof. Dr. Jörg Schwenk. He is now a postdoctoral researcher at the Karlsruhe Institute of Technology.

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