A hybrid combination of symmetric and asymmetric encryption technique with graph labeling

Abstract

Cryptography is the study of methodologies to promote secure communications by hiding or converting the original information to some unintelligible form. Graph Labeling is allocation of integers to edges and vertices of a graph following a set of conditions. Cryptography and graph theory are inextricably linked to each other since time immemorial. Here we implement cryptographic writing by combining the concepts of symmetric and asymmetric encryption techniques namely Pairwise Alternating Nested Caesar Cipher and RSA Algorithm with graph labeling. The former is an improved version of the popular symmetric encryption technique namely Caesar Cipher whereas the latter is an asymmetric cryptography algorithm widely used by modern computers to encrypt and decrypt messages. The plaintext undergoes hybrid encryption producing a Hybrid ciphertext which the sender passes to receiver as a Cryptographic writing comprising of Cipher Graph accompanied with a clue. We embrace Simply Sequential Additive labeling technique for ciphertext identification and the original plaintext is retrieved through corresponding decryption. The proposed methodology thus adopts the positive traits of both symmetric and asymmetric encryption ensuring double layer security of encrypted messages from adversaries, as knowledge of both Cryptography and Graph labeling is essential to proceed further.