An adaptive rendezvous data dissemination for irregular sensor networks with multiple sinks

Rendezvous mechanisms that mix pull and push dissemination strategies have significant importance as reporting mechanisms in sensor networks. Ordinary rendezvous approaches are optimized for flat architecture and face challenges such as irregularities in topology and the uncontrolled propagation of events. In this paper, we introduce TRDD, a topology adaptive rendezvous data dissemination approach for irregular, tiered sensor network architecture. In our proposal, sinks cooperatively build a query region QR along the perimeter of the network. This QR surrounds the network interior and forms a virtual closed region. The construction of the QR explicitly triggers interior nodes to initiate event paths to carry the events to the QR. The events could propagate in any direction yet the intersection at the query region is guaranteed. Different policies by which nodes could select the direction of events propagation (random, round-robin, centroid-based) are investigated. All of them guarantee the query-events intersection. In addition to the topological adaptation, the protocol has the ability to adapt its dissemination behavior according to the type of the submitted queries. The protocol is evaluated with simple analytical model and extensive software simulation. Comparisons to benchmark protocols that exemplify both pull and hybrid schemes are given. Results show the robustness and efficiency of the proposed solution in any network topology whether regular or irregular. Results also show noticeable reduction in the communication cost and an even distribution of events propagation through the network