engleski

Securing Communication in Chatter Application

Chatter is an Angular web application that offers registered users' ability to chat with other registered users. Users can chat with multiple users in a secure fashion. The main problem in designing a good backend for the Chatter application is dealing with message exchange security. In this paper, we will present a few security protocols and suggestions for exchanging secure messages. From single substitution ciphers (Caesar and Atbash) and multi-alphabet substitution ciphers (Vigenère and Playfair) to more complex like symmetric (XOR stream cipher and DES block ciphers) and asymmetric algorithms (using private and public key mechanisms with Diffie-Hellman key exchange and RSA algorithm with hash functions - SHA). We will present the pros and cons of using each algorithm by using man-in- the-middle attack and choose a secure asymmetric algorithm as the main security for exchanging messages at the end.

secure message exchange ; substitution cipher ; asymmetric algorithm ; hash ; man-in-the-middle attack

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