Using Distributed Mutual Exclusion for Coordinating Virtual Meeting in an Ubiquitous Chat System

The purpose of this paper is to present the application of distribute mutual exclusion for controlling the text message exchange in a ubiquitous chat named M-SynchroTalk. This chat allows tutors and students to be in contact even on the move. The main issue is to organize the entire communication when several students speak at the same time and about many subjects. All in all, the chat hold the dialog context controlling the message broadcast by means of the distributed mutual exclusion algorithms. In this context, just one student could send a message at a time. To achieve mutual exclusion in the ubiquitous chat, the centralized and the token ring algorithms have been developed. The centralized algorithm was implemented in two versions: human coordinator and computer coordinator. Preliminary results show that this solution provides a well-controlled environment suitable for M-Learning environments.