Opportunistic Communications in Infostation Systems: Delay and Stability Analysis

Infostation communication is an innovative communication paradigm thought to provide connectivity in isolated areas. In infostation communications, wireless ports are deployed to act as gateways between the remote users and the communication infrastructure. However, users are allowed to exchange data with the infrastructure only when in the coverage area of one of them. In order to provide further connectivity to remote users far away from infostations, mobile nodes are assumed to be used to collect data at remote users not in the range of the infostations and, then, upload this data when they come into proximity of the infostation. In order for this process to be successful, the system stability conditions should be identified. More in depth, we denote collection process the process representing the data packets collected by the mobile node in the time between two consecutive visits of infostations and upload process the process representing the number of data packets delivered by the mobile node to the infostation. In this paper we derive conditions when the average of the upload process is higher than the average of the collection process. To this purpose a diffusion approach inherited from physics is presented and design guidelines for stable system design are identified.