Synchronization of Multi-hop Wireless Sensor Networks at the Application layer

Time synchronization is a key issue in wireless sensor networks; timestamping collected data, tasks scheduling, and efficient communications are just some applications. From all the existing techniques to achieve synchronization, those based on precisely time-stamping sync messages are the most accu...

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Detalles Bibliográficos
Autores: Marco, A., Casas, R., Sevillano, J.L., Coarasa, V., Asensio, A., Obaidat, M.S.
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2011
País:España
Institución:Universidad de Zaragoza
Repositorio:Zaguán. Repositorio Digital de la Universidad de Zaragoza
OAI Identifier:oai:zaguan.unizar.es:130911
Acceso en línea:http://zaguan.unizar.es/record/130911
Access Level:acceso abierto
Descripción
Sumario:Time synchronization is a key issue in wireless sensor networks; timestamping collected data, tasks scheduling, and efficient communications are just some applications. From all the existing techniques to achieve synchronization, those based on precisely time-stamping sync messages are the most accurate. However, working with standard protocols such as Bluetooth or ZigBee usually prevents the user from accessing lower layers and consequently reduces accuracy. A receiver-to-receiver schema improves timestamping performance because it eliminates the largest non-deterministic error at the sender's side: the medium access time. Nevertheless, utilization of existing methods in multihop networks is not feasible since the amount of extra traffic required is excessive. In this article, we present a method that allows accurate synchronization of large multihop networks, working at the application layer while keeping the message exchange to a minimum. Through an extensive experimental study, we evaluate the protocol’s performance and discuss the factors that influence synchronization accuracy the most.