On Modeling the Coexistence of WiFi and Wireless Sensor Networks

The explosion in the number of WiFi and Wireless Sensor Network (WSN) deployments is exacerbating the coexistence problem, observed and reported in the literature as a significant performance degradation in co-located networks employing the two different wireless standards. The wireless coexistence problem has, thus far, been studied primarily using real hardware, due to the lack of analytical results and lack of good wireless coexistence models in network simulators. Thus, the progress on addressing the wireless coexistence issues has been slow. This paper presents the first analytical model and the first protocol coexistence simulator for coexisting WiFi and WSNs. We derive analytically, using Markov chains, the normalized saturated throughput of coexisting WiFi and WSNs, simulate the protocol coexistence using Monte Carlo methods, and validate our results through extensive experiments on real hardware (~4 million and ~60 million WSN and WiFi packets, respectively). These tools can be used for convenient and accurate performance estimation of medium-large scale deployments.