Instant Messaging Systems

The number of users of instant messaging (IM) has significantly increased in the last few years. Commercial providers are using closed centralized networks and do not enable users to communicate with other networks, although standardized protocols for IM do exist. The present thesis explores an alternative option of IM with the use of the XMPP protocol and a federated network of servers. Furthermore, it includes a description of the basic purpose, additional services and security requirements of IM. In addition, there is a description of the architecture and properties of the XMPP protocol and security tools for end-to-end security. The main goal of the present thesis is to set up an IM open-source Prosody server, and to analyse the possibilities and the use of open-source clients. The conclusion of the thesis presents the advantages and disadvantages of open-source solution versus commercial providers