January 23, 2012
Hosted by: Columbia CS/EE Networking Seminar
Speaker: Peter van de Ven , Goldstine Postdoctoral Fellow (IBM T.J. Watson Research Lab)
Wireless networks equipped with the CSMA protocol are subject to collisions due to interference. For a given interference range we investigate the tradeoff between collisions (hidden nodes) and unused capacity (exposed nodes). We show that the sensing range that maximizes throughput critically depends on the activation rate of nodes. For infinite line networks, we prove the existence of a threshold: when the activation rate is below this threshold the optimal sensing range is small (to maximize spatial reuse). When the activation rate is above the threshold the optimal sensing range is just large enough to preclude all collisions. Simulations suggest that this threshold policy extends to more complex linear and non-linear topologies.
Peter van de Ven received the M.Sc. degree in Applied Mathematics in 2007 from Eindhoven University of Technology, The Netherlands; from 2007-2011, he was a Ph.D. student at EUT working on stochastic models for wireless networks. He is currently the Goldstine Postdoctoral Fellow at the IBM T.J. Watson Research Lab. His research interests are in scheduling, queuing theory and the performance analysis of wireless networks