DynaChannAl: dynamic channel allocation with minimal end-to-end delay for two-tier wireless sensor networks

AbstractWith recent advances in wireless communication, networking, and low powersensor technology, wireless sensor network (WSN) systems have begun to takesigni cant roles in various applications ranging from environmental sensing tomobile healthcare sensing. While some WSN applications only require a lim-ited amount of bandwidth, new emerging applications operate with a notice-ably large amount of data transfers. One way to deal with such applicationsis to maximize the available capacity by utilizing the use of multiple wirelesschannels. This work proposes DynaChannAl, a distributed dynamic wirelesschannel algorithm with the goal of e ectively distributing nodes on multiplewireless channels in WSN systems. Speci cally, DynaChannAl targets applica-tions where mobile nodes connect to a pre-existing wireless backbone and takesthe expected end-to-end queuing delay as its core metric. We use the link qual-ity indicator (LQI) values provided by IEEE 802.15.4 radios white-list potentiallinks with good link quality and evaluate such links with the aggregated packettransmission latency at each hop. Our approach is useful for applications thatrequire minimal end-to-end delay (i.e., healthcare applications). DynaChannAlis a light weight and highly adoptable scheme that can be easily incorporatedwith various pre-developed components and pre-deployed applications. We eval-uate DynaChannAl in on a 45 node WSN testbed. As the rst study to considerend-to-end latency as the core metric for channel allocation in WSN systems, theexperimental results indicate that DynaChannAl successfully distributes multi-ple (mobile) source nodes on di erent wireless channels and enables the nodesto select wireless channel and links that can minimize the end-to-end latency.Keywords: Wireless Sensor Networks, Dynamic Channel Allocation, LatencyAware Protocols