Combining Light-weight Cryptography with Arabic Text Steganography for Higher Security

Abstract

Light-weight Cryptography is a kind of cryptographic primitives that concentrates on optimizing encryption algorithms to run on small and resources-limited devices such as IoT devices. It is different from Conventional Cryptography methods that can work on systems with high power and memory capabilities. Arabic Text Steganography is the method of hiding messages within Arabic Text, so that any intruder cannot even detect there is a message hidden. The integration between the two techniques gives higher security level. The secret message is not only hidden with robust techniques, but is also encrypted with effective cryptographic methods. Some studies have used the idea of the integration between Cryptography and Steganography methods. The work in this thesis added the value of the choice between different cryptographic techniques. The study suggested the usage of the Arabic Feature, all of the Diacritics, instead of using some of them. The work in the thesis have used Light-weight Cryptography (LWC) using three encryption algorithms which are, AES, DES and IDEA. The message is encrypted using one of the three algorithms and it is turned into encrypted message in a form of binary bits. After the message is encrypted, it goes though Arabic Text Steganography phase. The steganography uses all of the diacritics in Arabic to hide the encrypted bits within the cover-text. The chosen cover-text in the study is Arabic historical poetry. The output of the integration is a Stego-file, which includes an encrypted hidden message. The study showed the results from different prospective, which are mainly Security and Capacity. Each aspect is demonstrated using different experiment such as Histogram analysis, PSNR and Letters Variations. The experiment have tested the usage of different bits count to record the best case hiding the message. The study added the value of using all of the diacritics and compared it with a previous study of using two diacritics only. The research analyzed the capacity of hidden bits within the historical poetry and within samples from the holy Quran to verify the results. Security analysis has been part of the experiment in the study to check which cryptographic algorithms gives better results and determine the best number of bits to hide. The histogram analysis includes using different letters, starting from two letters up to 16 in the encryption phase using the three algorithm The results have indicated that AES gives better results in terms of capacity. The results have shown that using the full diacritics is better than using two diacritics in terms of capacity and the value changes with the diacritics in the cover text. The security quantity test is suggesting using AES in the 2-layer hiding information. While observing all of the histograms for all the letters used, IDEA gives the nearest histogram compared to the original one. The results of PSNR analysis are showing interesting similar values indicating that all three methods are acceptable from security visual comparisons point of view. The research uses various ways to test the system effectiveness and robustness. It compares the results with similar studies and uses different cover-text. The limitation in the study is the variance of determining which encryption method is the most effective.