Finite-size effects in low-density parity-check codes applied to cryptography

Abstract

Low density parity check error-correcting codes can be applied as an efficient public key cryptosystem. The scheme, based on the computational difficulty in factorising dense matrices, has been studied so far in the limit of infinite system size. In this work we study numerically the finite-size effects in such a system, such that may have a significant impact on the reliability of the cryptosystem, and we derive the corresponding practical limitations in using these algorithms. We also describe the difficulties we encountered in using a similar approach to devise an electronic signature cryptosystem.

Date of Award	Sept 2001
Original language	English
Awarding Institution	Aston University