... on an entire network. B. Attacks Wireless networks are more vulnerable to security attacks than wired networks, due to the broadcast nature of the transmission medium. These attacks are normally ... conventional networks. In this paper, we investigate the security related issues and challenges in wireless sensor networks. We identify the security threats, review proposed security mechanisms ... security mechanisms for wireless sensor networks. Keywords: Wireless Sensor Networks (WSNs), Security, Threats, Attacks, I. INTRODUCTION Wireless sensor network (WSN) is a heterogeneous system...