Future Internet_**2010**, \(2\), 96-125; doi:10.3390/fi2020096  
_future internet_  
**ISSN 1999-5903**  
www.mdpi.com/journal/futureinternet  
Survey on Wireless Sensor Network Technologies for Industrial Automation: The Security and Quality of Service Perspectives  
**[PERSON] \({}^{1,\star}\), [PERSON] \({}^{2}\) and [PERSON] \({}^{1}\)**  
\({}^{1}\) Secure Mobile Networking Lab, Center for Advanced Security Research Darmstadt, Department of Computer Science, Technische Universitat Darmstadt, Mornewegstr. 32, 64293 Darmstadt, Germany;  
E-Mail: [EMAIL_ADDRESS]  
\({}^{2}\) Multimedia Communications Lab, Department of Computer Science, Technische Universitat Darmstadt, Rundeturmstr. 10, 64283 Darmstadt, Germany;  
E-Mail: [EMAIL_ADDRESS]  
\({}^{\star}\) Author to whom correspondence should be addressed;  
E-Mail: [EMAIL_ADDRESS]; Tel. : +49 6151 16-70923  
_Received: 30 January 2010; in revised form: 19 March 2010 / Accepted: 24 March 2010 / Published: 8 April 2010_  
**Abstract:** Wireless Sensor Networks (WSNs) are gradually adopted in the industrial world due to their advantages over wired networks. In addition to saving cabling costs, WSNs widen the realm of environments feasible for monitoring. They thus add sensing and acting capabilities to objects in the physical world and allow for communication among these objects or with services in the future Internet. However, the acceptance of WSNs by the industrial automation community is impeded by open issues, such as security guarantees and provision of Quality of Service (QoS). To examine both of these perspectives, we select and survey relevant WSN technologies dedicated to industrial automation. We determine QoS requirements and carry out a threat analysis, which act as basis of our evaluation of the current state-of-the-art. According to the results of this evaluation, we identify and discuss open research issues. **Keywords:** Wireless Sensor Networks; Industrial Automation; Quality of Service; Security; State-of-the-art; WirelessHART; ISA100.11a-2009; ZigBee; Wireless Interface for Sensors and Actuators ; 802.15.4e Factory Automation MAC LayerIntroduction  
Industrial automation has been successfully introduced in a countless amount of industries ranging from food to energy industries. Even if the products differ from one industry to another, the automated processes can be classified according to three main layers as proposed by [1]: the plant-floor automation layer, the manufacturing execution system layer and the enterprise resource planning layer. Internet technology can be considered as the link that interconnects all these layers and allows for information exchange. For example, it serves as a backbone to interconnect different production locations within one enterprise, to transfer production control data in near real-time to the headquarters or to integrate suppliers into a production workflow. Within the scope of this survey, we focus on the plant-floor automation layer including sensors, switches, programmable controllers and motor starters (Fig. 1) that ensure the correct operation of machines and execution of processes, while the remaining layers are dedicated to the optimization of the production by managing resource allocation and operation scheduling for example. In addition to productivity gain and precision improvement, the automation of processes at the plant-floor automation layer allows the replacement of workers in harsh and hazardous environments or assigned to tedious tasks [2]. The WSNs are part of this layer and can be used for multiple purposes, such as monitoring synchronous or asynchronous events that require periodic data collection or detecting exceptional events, respectively [3]. For example, vibration, heat or thermal sensors can be deployed in proximity of machines to monitor their health. The analysis of the measured parameters can allow the detection of abnormal operating conditions and aids therefore in preventing potential machine failure.