关键词：无线传感器网络；接收器；源节点
摘 要：Since wireless sensor networks (WSNs) are vulnerable to malicious attacks due to their characteristics, privacy is a critical issue in many WSN applications. In this chapter, we discuss existing privacy enhancing technologies designed for protecting system privacy, data privacy and context privacy in wireless sensor networks (WSNs). The privacy-preserving techniques for the system privacy hide the information about the location of source nodes and the location of receiver nodes. The data privacy techniques mainly protect the privacy of data content and in-network data aggregation. The context privacy refers to location privacy of users and the temporal privacy of events. For each of these three kinds of privacy in WSNs, we describe its threats and illustrate its existing privacy-preserving techniques. More importantly, we make comparisons between different techniques and indicate their strengths and weaknesses. We also discuss possible improvement, thus highlighting some research trends in this area.