2008 Third International Conference on Risks and Security of Internet and Systems (CRiSIS 2008) proceedings : Tozeur, Tunisia, October 28-30, 2008 / edited by Mohamed Jmaiel and Mohamed Mosbah ; technically co-sponsored by IEEE-Tunisia Section ; co-organized and in cooperation with Research Unit on Development and Control of Distributed Applications, Research Laboratory on Computer Science of Bordeaux, National Agency of Computer Security ; supported by Scientific Association of Research Support and Technological Innovation ... [et al.].