New Multiplicative Knapsack-Type Public Key Cryptosystems

Shinya KIUCHI  Yasuyuki MURAKAMI  Masao KASAHARA  

Publication
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences   Vol.E84-A   No.1   pp.188-196
Publication Date: 2001/01/01
Online ISSN: 
DOI: 
Print ISSN: 0916-8508
Type of Manuscript: Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
Morii-Kasahara cryptosystem,  Schalkwijk algorithm,  high rate,  fast encryption,  discrete logarithm problem,  

Full Text: PDF(354.2KB)
>>Buy this Article


Summary: 
In this paper, first, we propose two of the high rate methods based on Morii-Kasahara cryptosystem. Method A-I is based on Schalkwijk algorithm. Method A-II is based on the extended Schalkwijk algorithm, which is proposed in this paper. We then show that these proposed methods can yield a higher rate compared with ElGamal cryptosystem. Next, we also propose two methods for a fast encryption by dividing the message vector into several pieces. Regarding each of the divided vectors as an index, we can realize a fast transformation of the index into a limited weight vector. In Method B-I, Schalkwijk algorithm is used for the fast transformation. In Method B-II, the fast transformation is realized with the method of table-lookup. These methods can realize a faster encryption than Method A-I, Method A-II and Morii-Kasahara cryptosystem. The security of these proposed methods are based on the security of Morii-Kasahara cryptosystem.