The Department of Computer Science awarded a PhD to student Suhad Muhajir Karim for her thesis tagged (New update of analogue encryption algorithms based on reduced polynomials for Galous Field) Multi-level key encryption algorthim based on irreducible polynomials Galois Field Wednesday 08/19/2020 in the discussion room in the building of the Computer Science Department. The discussion committee consisted of:
- Prof. Dr. Ziad Tariq Mustafa as chairman
- Prof. Hala Bahjat Abdel-Wahab, member
- Prof. Alaa Kazem Farhan, member
- Prof. Nidaa Falih Hasan, member
- Prof. Muhammad Abdullah Nasser, member
- Prof. Abdel-Moneim Saleh Rahma, member and supervisor
The thesis aims to present a new development on analogue encryption algorithms (DES, Blowfish, Twofish, etc.) AES, RC4 and MD5)
In addition to providing a hybrid between two algorithms (RC4 & MD5). This is to enhance security. This is achieved by replacing the base binary operation (XOR) in each of these algorithms' rounds with two new proposed operations. The first proposition is a new process called (#E) based on the application of multi-state tables created based on the addition process in GF (2n) with variable size (n) blocks may be (1, 2, 4 and 8 blocks). The second proposition represents another process called cyclic group # operation (CGE #) with multi-state tables created based on the term irreducible polynomial group in GF (28). The two operations require additional keys to control the number of bits and the tables used in Encryption and decryption. The proposed algorithms were applied to text and images and were examined using a number of security criteria, including: complexity, coding time, randomness assay (NIST), statistical gradient analysis, correlation coefficients, number of change rate points (NPCR) and mean intensity of standard change (UACI)).