Hrishikesh Mahato

Kalika Prasad, Hrishikesh Mahato, Munesh Kumari

In this article, we have proposed a generalized Lucas matrix (recursive matrix of higher order) having relation with generalized Fibonacci sequences and established many special properties in addition to that usual matrix algebra. Further, we have proposed a modified public key cryptography using these matrices as keys in Affine cipher and key agreement for encryption-decryption with the combination of terms of generalized Lucas sequences under residue operations. In this scheme, instead of exchanging the whole key matrix, only a pair of numbers(parameters) need to be exchanged, which reduces the time complexity as well as space complexity of the key transmission and has a large key-space.

Kalika Prasad, Hrishikesh Mahato

In this article, we have proposed a public key cryptography using Affine-Hill cipher with a generalized Fibonacci matrix(called multinacci matrix). Also proposed a key establishment(exchange of key matrix $K=Q_λ^{k}$ of order $λ\timesλ$ for encryption-decryption) scheme with the help of multinacci sequences under prime modulo. In this scheme, instead of exchanging key matrix, we need to exchange the only pair of numbers $(λ, k)$, which reduces the time complexity as well as space complexity and comes with a large key-space.

Shipra Kumari, Hrishikesh Mahato

In this article, an encryption scheme based on (-1, 1) conference matrix has been developed. The decryption key comprising of fixed number of positive integers with prime power yields the high level security of message. Some popular attacks has been discussed in the context of cryptoanalysis and observed that it is robust against the popular cipher attack and the security of the information does not compromise.