An Improved Pseudorandom Generator Based on Hardness of Factoring

  • Nenad Dedić
  • Leonid Reyzin
  • Salil Vadhan
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2576)


We present a simple to implement and efficient pseudorandom generator based on the factoring assumption. It outputs more than pn/2 pseudorandom bits per p exponentiations, each with the same base and an exponent shorter than n/2 bits. Our generator is based on results by Håstad, Schrift and Shamir [HSS93], but unlike their generator and its improvement by Goldreich and Rosen [GR00], it does not use hashing or extractors, and is thus simpler and somewhat more efficient. In addition, we present a general technique that can be used to speed up pseudorandom generators based on iterating one-way permutations. We construct our generator by applying this technique to results of [HSS93]. We also show how the generator given by Gennaro [Gen00] can be simply derived from results of Patel and Sundaram [PS98] using our technique.


Hash Function Discrete Logarithm Quadratic Residue Pseudorandom Generator Modular Exponentiation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Nenad Dedić
    • 1
  • Leonid Reyzin
    • 1
  • Salil Vadhan
    • 2
  1. 1.Boston University Computer ScienceBostonUSA
  2. 2.Harvard University DEASCambridgeUSA

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