Sliding Window Method for NTRU

  • Mun-Kyu Lee
  • Jung Woo Kim
  • Jeong Eun Song
  • Kunsoo Park
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4521)


The NTRU cryptosystem is a ring-based public key system using hard problems over lattices. There has been an extensive research on efficient implementation of NTRU operations, including recent results such as Bailey et al.’s software implementation over a resource-constrained device and Gaubatz et al.’s hardware implementation using only 3,000 gates. In this paper, we present a new algorithm to improve further the performance of NTRU. We speed up the encryption and decryption operations of NTRU up to 32% using some temporary memory, and if we can use precomputation, then the speed-up becomes up to 37%. Our method is based on the observation that specific sub-operations are repeated frequently in the underlying polynomial operations of NTRU.


Simple Pattern Convolution Operation Modular Reduction Temporary Memory Convolution Algorithm 
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 Berlin Heidelberg 2007

Authors and Affiliations

  • Mun-Kyu Lee
    • 1
  • Jung Woo Kim
    • 2
  • Jeong Eun Song
    • 1
  • Kunsoo Park
    • 2
  1. 1.School of Computer Science and Engineering, Inha University, Incheon 402-751Korea
  2. 2.School of Computer Science and Engineering, Seoul National University, Seoul 151-742Korea

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