Encyclopedia of Cryptography and Security

2005 Edition
| Editors: Henk C. A. van Tilborg

Trapdoor One-Way Function

  • Matt Robshaw
Reference work entry
DOI: https://doi.org/10.1007/0-387-23483-7_436

A trapdoor one-way function is a one-way function with an additional requirement. Informally, a one-way function might be described as a function for which evaluation in one direction is straightforward, while computation in the reverse direction is far more difficult. Such a function becomes a trapdoor one-way function when we add the requirement that computation in the reverse direction becomes straightforward when some additional (trapdoor) information is revealed [3].

While there are alternative descriptions [2] we might describe a trapdoor one-way function as a function f with domain X and range (codomain) Y where f (x) is ‘easy’ to compute for all \(x \in X\)

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© International Federation for Information Processing 2005

Authors and Affiliations

  • Matt Robshaw

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