关键词：无线传感器；问题；挑战；方法
摘 要：Wireless sensor networks (WSNs) have generated immense interest among researches for the last few years motivated by several theoretical and practical challenges. The increase in interest is mainly attributed to new applications designed with large scale networks consisting of devices capable of performing computations on the sensed data and finally processing the data for transmitting to remote locations. Providing security to WSNs plays a major role as these networks are generally deployed in inaccessible terrain and also for their communication being in the wireless domain. These reasons impose security mechanisms to be employed on the highly vulnerable sensor networks that are robust enough to handle attacks from adversaries. WSNs consist of nodes having limited resources and therefore classical security measures applicable in traditional networks cannot be applied here. So the need of the hour is using systems that lie within the boundary of the sensor nodes resource potential as well competent enough to handle attacks. Intrusion detection is one such defense used in sensor networks having the ability to detect unknown attacks and finding means to thwart them. Researches have found intrusion detection system (IDS) to be very much compatible in sensor networks. Therefore intrusion detection holds a very prominent research area for researchers. So familiarity with this promising research field will surely benefit the researchers. Keeping this in mind we survey the major topics of intrusion detection in WSNs. The survey work presents topics such as the architectural models used in the different approaches for intrusion detection, different intrusion detection techniques and highlights intrusion detection methods applicable for the different layers in sensor networks. The earlier achievements in intrusion detection in WSNs are also summarized along with more recent works and existing problems are discussed. We also give an insight into the possible directions for future work in intrusion detection involving different aspects in sensor networks.