PORT: a price-oriented reliable transport protocol for wireless sensor networks

In wireless sensor networks, to obtain reliability and minimize energy consumption, a dynamic rate-control and congestion-avoidance transport scheme is very important. We notice that reporting packets may contribute to the sink´s fidelity of its knowledge on the phenomenon of interest to different extents. Thus, reliability cannot simply be measured by the sink´s total incoming packet rate as considered in current schemes. Also, communication costs between sources and the sink may be different and may change dynamically. Based on these considerations, we propose PORT (price-oriented reliable transport protocol) to facilitate the sink to achieve reliability. Under the constraint that the sink must obtain enough fidelity for reliability purpose, PORT minimizes energy consumption with two schemes. One is based on the sink´s application-based optimization approach that feeds back the optimal reporting rates. The other is a locally optimal routing scheme according to the feedback of downstream communication conditions. PORT can adapt well to the communication conditions for energy saving while maintaining the necessary level of reliability. Simulation results in an application case study demonstrate the effectiveness of PORT