Hybrid Cryptosystem Analysis by Using The Combination of Vigenere Cipher and RSA for Text Security

Abstract

The development of Information and Communication Technology (ICT) brought many benefits to the needs of human life, especially the needs for the information which is increasingly obtained easily. This is in line with the need for information security from parties who want to get important data so that it can harm the owner of the source data. One of the data safeguards used is cryptography. Once the importance of data security, almost all activities of human life cannot be separated from cryptography.  According to the key used, cryptography can be divided into two, namely: symmetric cryptography and asymmetric cryptography, which has its own advantages and disadvantages. The objective of this research is to analyze through the calculation results so that they can be applied to overcome the weaknesses that occur from the two types of cryptography. The hybrid cryptosystem coding method is always used to overcome the weaknesses of the two cryptographs. The coding process in this research uses two cryptographic algorithms. They are the Vigenere Cipher algorithm as an example of a symmetrical algorithm and the RSA (Rivest Shamir Adleman) algorithm, which is an example of an asymmetric algorithm. The result of the research on the calculation shows that there is increased security in the encryption because there will be two encodings, namely the coding of the messages by the Vigenere Cipher cryptographic algorithm and key coding by the RSA cryptographic algorithm