An enhancementof the intru encryption algorithm applied in mobile instant messaging client applications
- Undergraduate Thesis: (Bachelor of Science in Electronics Engineering) - Pamantasan ng Lungsod ng Maynila, 2024.
ABSTRACT: Cryptosystems have been an important aspect of the cyber security industry in protecting users against the current rise of cyber criminals and attacks. Public asymmetric cryptosystem, for example, ensures that two keys, a public and a private key, can both protect sensitive and private information against unwanted attackers and hackers. Information sensitive to users often originate from sources such as instant messaging applications that involves rapid exchange of data between two users at the same time. There are lots of encryption algorithm used to counter these attacks and one of this is an INTRU-based Cryptosystem called. ITRU Encryption Algorithm . The proponents of this study had analyzed the current existing ITRU Encryption Algorithm, comparing it against other encryption and stating the problems that the existing algorithm had, and enhanced the algorithm by resolving the analyzed problems so that it could be implemented on a mobile instant messaging client application. It was observed that the existing algorithm was unable to accept and recognize Unicode characters due to the existing algorithm limiting itself to the ASCII encoding scheme of characters. The algorithm also did not trap errors produced when creating the public key using the Extended Euclidean Method. Finally, the algorithm creates an encrypted message with a pattern-like sequence similar to the patterns of the plaintext message due to its one-to-one correspondence of encryption. After further analysis and study of the existing algorithm, the proponents added changes and enhancements that had resolved the problems found before. First, the ASCII encoding scheme was changed into a Byte encoding scheme to expand the scope of encoding scheme that the algorithms uses beyond the ASCII characters. Next, the parameter generation of p was changed from being a constant 1000 to a prime number between m and 630 to prevent the errors produced when generating the keys. Finally, the block cipher algorithm of XOR operations between blocks of messages was implemented to the algorithm itself to randomize the generated ciphertext. The results of the study had shown that the enhanced algorithm was able to accept Unicode characters, particularly Emoji characters, as inputs of data. The enhanced algorithm also produced a zero percent key error rate multiple rounds of testing. Lastly, the enhanced algorithm produced a completely randomized ciphertext with no noticeable one-to-one correspondence with the plaintext message. The enhanced algorithm had been applied to an instant messaging application created by the proponents and had shown similar results from the simulation of the proposed algorithm. In conclusion, the proponents had successfully enhanced the existing ITRU encryption algorithm and had resolved all analyzed problems of the existing algorithm. The proposed algorithm had also been successfully implemented to an instant messaging application. The proponents recommend future studies to consider other platforms for messaging applications such as IOS and Windows in implementing the ITRU encryption algorithm.