Title
Proposal for Piece In Hand Matrix Ver.2: General Concept for Enhancing Security of Multivariate Public Key Cryptosystems
Abstract
We proposed the concept, piece in hand (soldiers in hand) matrix and have developed the framework based on the concept so far. The piece in hand matrix is a general concept which can be applicable to any type of multivariate public key cryptosystems to enhance their security. In this paper, we make improvements in the PH matrix method as follows. (i) In the PH matrix method, an arbitrary number of additional variables can be introduced to the random polynomial term in the public key, which is eliminated by the multiplication of the PH matrix to the public key in the decryption. Thus these additional variables enables the public key to have more than one solution, and therefore increases the diculty to solve the public key. We show, in an experimental manner, that the PH matrix method improved in this way is secure even against the Grobner basis attack. (ii) In the nonlinear PH matrix method proposed previously, the degree of polynomials in the public key is more than two, and this may cause an undesirable increase in the length of the public key. In this paper, we propose a nonlinear PH matrix method, where the degree of the public key is kept the same as the degree of the public key of the original cryptosystem, which is normally
Year
Venue
Keywords
2006
IACR Cryptology ePrint Archive
two. key words: public key cryptosystem,soldiers in hand,multivariate public key cryptosystem,piece in hand concept,multivariate polynomial
DocType
Volume
Citations 
Journal
2006
1
PageRank 
References 
Authors
0.35
2
3
Name
Order
Citations
PageRank
Shigeo Tsujii1598131.15
Kohtaro Tadaki211817.04
Ryou Fujita3293.97