Configuration Interface for Industrial Wireless Sensor Networks José Cecílio 1 , João Costa 1 , Pedro Martins 1 , Pedro Furtado 1 1 University of Coimbra, Coimbra, Portugal jcecilio@dei.uc.pt, jpcosta@dei.uc.pt, pmom@student.dei.uc.pt, pnf@dei.uc.pt Abstract— Wireless sensor networks (WSNs) are deployed to sense, monitor and act on the environment. Some applications of these networks, especially in industrial sense and react scenarios, require high performance and guaranties. Our work is focused on building a system that allows configuring/reconfiguring alarms, actions or closed-loop techniques in the context of GINSENG project – wireless sensor networks with performance control guarantees. We propose an approach for interaction with real-world devices through a web services interface, allowing users to configure and apply various operations, including complex closed-loop techniques that monitor and act over any actuator in the WSN. To allow the interaction between a client application and the motes we implemented an API to access services of the motes. Keywords - WSN, Configuration/Reconfiguration, Industrial application I. INTRODUCTION Sensor Networks are used nowadays in many application contexts, with quite different characteristics. One application scenario of these networks consists on industrial environments. In an industrial setting for monitoring-and- control applications, easy configuration and reconfiguration capabilities become important during deployment and tests, where issues such as latencies may dictate modification. During the lifetime of the network, a deployment may not meet all requirements. It is important to check if all requirements are guaranteed, if not, it is needed to change something in the network. Closed-loop control is an important issue in industrial settings. Since sensor motes have limited computation capability and control computations may require operation on values coming from multiple sensors, immediate sensor- triggered control will typically be only for emergency actuation (e.g. opening a valve if pressure goes beyond an emergency level). More complex closed-loop control computations can be done in a control workstation, subject to larger latencies and more data (e.g. multiple samples, inputs from multiple sensors). In this paper, we present an approach to connect wireless sensor or actuator nodes to a web services interface for configuring and applying various operations, including complex closed-loop control techniques. This work is done in the context of a European GINSENG project – wireless sensor networks with performance control guarantees. Sensors and actuators are represented as resources of the corresponding node and are made accessible using a web service interface that establishes the communication with the nodes. Our main goal is to enable a flexible architecture where sensor networks data can be accessed by users to configure the system, including configuration of alarms, sending rates, closed-loop control and actions. We present our system architecture and show a user interface called GWeb. Lastly we show some results obtained from experimental tests done at Petrogal refinery, a critical environment where is needed to define alarms and actions to prevent accidents. II. RELATED WORK Our proposal consists on an application programming interface (API) that allows to configure/reconfigure a WSN for industrial applications. Related work includes strategies to connect a WSN to the internet and API to sensor networks. Interconnecting WSNs with the Internet is a subject that attracts a lot of attention of the research community in recent years. There are some different ways to interconnect TCP/IP networks with sensor networks. In this section we review three main types: using IP protocols, bridges or gateways. Using IP protocol, which assumes that sensor nodes are powerful enough to run a u-IP protocol [9]: by running u-IP protocol in WSNs, Internet users can access any sensor node by using IP address. But, the assumption that sensor nodes always have enough resources to support the overhead that is brought by the IP protocol stack is not feasible. Using only IP protocol is not suitable for application-specific WSNs, since different WSNs may have different requirements from applications. Using a bridge: In [10] authors proposed VIP Bridge to connect heterogeneous WSNs with IP based networks. Packets that come from one side will be translated into corresponding packet formats and sent to another side by this VIP Bridge. In this research different translators are used for translating different packet formats, e.g. ZigBee and Bluetooth, into IPv6 protocol packet format. Using a gateway: The most common approach for connecting sensor networks with an external network is using application-level gateway, e.g. GSN [11]. Different protocols in both side networks are translated in the application layer. In GSN, authors use wrappers to translate different protocols packet formats into unified data format. 2011 Workshops of International Conference on Advanced Information Networking and Applications 978-0-7695-4338-3/11 $26.00 © 2011 IEEE DOI 10.1109/WAINA.2011.72 447