Time-Stable Geocast in Intermittently Connected IEEE 802.11 MANETs

By geocast protocols, information can be directly disseminated to users of mobile devices who currently reside in selected geographical regions. Time-stable geocast protocols enhance these mechanisms by providing the information to the users in the regions for a specified duration. This becomes a challenging task under the harsh conditions in mobile ad-hoc networks with sparse user densities, especially if the information should be provided to a new user immediately when he enters a region. This paper introduces a new approach which increases the probability of a user to immediately receive respective information when he enters a region. It is based on an enlarged message forwarding region, being dynamically adapted depending on the currently perceived spatial user density. Besides, the paper presents the realization of the time-stable geocast mechanisms based on IEEE 802.11 technology.