Evaluation of Performance Characteristics of Polynomial based and Lattice based NRTU Cryptosystem

In order to achieve the security for the e-business application, generally, the organizations follow the cryptographic methods. The two widely accepted and used cryptographic methods are symmetric and asymmetric. The DES ideally belongs to the category of symmetric key cryptosystem and RSA, NTRU[3] belongs to the category of asymmetric key cryptosystem. NTRU (Nth degree truncated polynomial ring units) is a collection of mathematical algorithms based on manipulating lists of very small integers. NTRU is the first secure public key cryptosystem not based on factorization or discrete logarithmic problems. The keys are generated by having small potent polynomials from the ring of truncated polynomials. NTRU can also be implemented using matrices instead of polynomials [4, 5]. We proceed with the encryption and decryption of the plain text required by implementing the algorithms of both the approaches of NTRU cryptosystems. It is already shown that the matrix approach is algorithmically better than the polynomial approach of NTRU cryptosystem [5]. We propose and test both the methods for variable sized text files, using polynomial and matrix cryptosystems. This paper presents the comparative study of polynomial NTRU and matrix NTRU algorithms for variable sized text files as input. The final results were observed using Mathematica5.1, analyzed and compared so as to identify which method is appropriate to the business needs.