Primary Key Encryption Using Hill Cipher Chain (Case Study: STIE Mandala PMB Site)

Abstract

The condition of the world experiencing the COVID-19 pandemic has resulted in some daily activities limited by health protocols. The Indonesian government's policy in the academic field has forced STIE Mandala Jember, as one of the private universities, to implement online-based new student admissions. The registrant's identity must be kept confidential during the online-based new student registration process, so the running system needs an identity coding (encryption) process. Hill Cipher is a cryptographic algorithm that utilizes the multiplication of matrix inverse operations. In ordinary Hill Cipher, to encrypt the entire plaintext, a key is needed. In this paper, we will modify the Hill Cipher named Hill Cipher Chain. The process of chained Hill Cipher will encrypt and decrypt the primary key based on the previous character. Firstly, we will encrypt the primary key with the key from the next column of the database. In this case, we use the name column. The encryption result will be used as a key for the subsequent character encryption. Implementation of this method makes the difficulty level of decryption more complex than the ordinary Hill Cipher, which only uses one key for all so that the security of the data obtained is also getting better.

NFC Data Security Using Hill Cipher

“…[5] The Hill Cipher is a polygraphic substitution cipher based on linear algebra [6]. It operates on blocks of letters, rather than single letters as in traditional substitution ciphers [7]…”

Hill Matrix and Radix-64 Bit Algorithm to Preserve Data Confidentiality

“…When the recipient decrypts the file, they access it using the same method and Key. Rohim et al [34] wanted to encrypt primary key data. Researchers modified the Hill Cipher algorithm to solve this problem and developed a new algorithm called the Hill Cipher Chain Algorithm.…”

“…In 2021 [34], researchers developed a symmetric hill cipher encryption algorithm that encrypts and decrypts data with the same Key. After encrypting the data, the data and the Key are uploaded to the server.…”

“…The advantage of deriving the Key from each encryption time text is that the data can be transmitted across the network in a reliable form. Various researchers [31][32][33][34][35] developed different algorithms to secure data in which the length of the plaintext and the length of the ciphertext was same. A static key was then used to secure the data, with the help of which the data was encrypted and decrypted.…”