A tutorial on using ElGamal cryptosystem and RC4-P1 cipher in a hybrid scheme

Abstract

Digital document is a form of information that can be transmitted over a digital channel. Public key cryptosystem such as ElGamal may provide secure transmission of digital document. However, securing a large document in.docx extension, it is usually not efficient to use public key cryptosystem directly, since the ciphertext generated is usually much larger than the original document itself, making it difficult to transmit. In this research, this problem is avoided by using a scheme called hybrid cryptosystem. A combination of ElGamal algorithm and RC4-P1 cipher will be used to perform the hybrid cryptosystem scheme for data security. The RC4-P1 cipher is the latest variant of RC4 cipher and relatively shorter time to do the encryption and decryption process, but only by using single-key.