Improving Geo-casting by Combining Any-cast and Hovering Information

Geocasting is a variation on the notion of multicasting in which messages are deliver to the nodes residing in a specific area. This paper proposed a novel geocast protocol based on any-cast and hovering information in order to improve the performance by balancing load between server and local nodes. Thus proposed technique has two phases for geocasting, 1) any-cast from source to geocast region and 2) distribution of messages using hovering information. Our results has shown that using hovering information and creating replicas for geocasting messages we can reduce the overhead of broadcasting messages several time that helps in reducing the bandwidth

Reliable geocasting for random-access underwater acoustic sensor networks

a b s t r a c t Reliable data delivery for underwater acoustic sensor networks is a major concern in applications such as surveillance, data collection, navigation, and ocean monitoring. Geocasting is a crucial communication primitive needed to support these applications, which consists in transmitting one or multiple consecutive data packets -all carrying an atomic message -to nodes located in a certain geographic region. In this article, two versions of a distributed, reliable, and efficient underwater geocasting solution (based on different degrees of neighbor information) are proposed for underwater networks whose acoustic modems use random-access Medium Access Control (MAC) protocols. By jointly considering the position uncertainty of nodes as well as the MAC and routing functionalities, packet transmissions are prioritized and scheduled so to maximize link reliability while limiting the end-to-end geocasting delay. Moreover, a simple yet effective timer-based mechanism is designed to limit the number of transmissions by selecting only a subset of neighbors for packet forwarding. Performance is evaluated and compared via thorough simulations against existing geocasting solutions tuned for the underwater environment that were originally designed for terrestrial wireless networks