Thesis (MSc) - Cyprus International University. Institute of Graduate Studies and Research Information Technologies Department

Includes bibliography (sheets 76-83)

ABSTRACT
The unsecured electronic document can be exposed to a data breach, whereby sensitive
or confidential data is copied, transmitted, viewed, stolen, or used by an unauthorized
person. This study aims to develop an encryption and decryption software entitled
VBDES22 for document files based on the comparison of converting plaintext into
cipher text (Encrypt) and converting cipher text into plaintext (Decrypt), using a key
known to both sender and receiver of such document. This study provides a
performance comparison simulation evaluation to analyze four encryption algorithms
i.e. Data Encryption Algorithms, Rivest Cipher2 Algorithm (RC2), Triple Data
Encryption Standard (3DES), and Advanced Encryption Standard (AES) to choose the
best in terms of speed. The comparison has been conducted by running several
encryption settings to process different sizes of data blocks to evaluate the algorithm's
encryption/decryption speed. The simulation has been conducted using Visual
basic.Net by measuring the time taken for the algorithms to encrypt and decrypt the
file in different data block sizes using an electronic codebook (ECB). As a result, four
algorithms are analyzed and found that Data Encryption Standard (DES) performs
encryption/decryption faster than Advanced Encryption Standard (AES), Rivest
Cipher2 (RC2), and Triple Data Encryption Standard (3DES). Therefore, the Data
Encryption Standard (DES) was chosen for the VBDES22 development.
Keywords: Advanced Encryption Standard, Data Encryption Standard, Decrypt,
Electronic Code Book (ECB), Encrypt, Rivest Cipher2, Triple Data Encryption
Standard