IJCSMS International Journal of Computer Science and Management Studies, Vol. 12, Issue 03, Sept 2012 ISSN (Online): 2231-5268 www.ijcsms.com IJCSMS www.ijcsms.com 143 Attacks on Wireless Sensor Network: A Survey Dr. Yudhvir Singh 1 , Dheer Dhwaj Barak 2 , Vikas Siwach 3 , Prabha Rani 4 1 Associare Professor, Department of CSE, U.I.E.T, M.D.U. Rohtak -124001 (INDIA) dr.yudhvirs@gmail.com 2 Assistant Professor, Department of CSE, HIT Asodha M.D.U. Rohtak -124001 (INDIA) barakdheer410@gmail.com 3 Assistant Professor, Department of CSE, U.I.E.T, M.D.U. Rohtak -124001 (INDIA) singhvikash94@yahoo.com 4 Department of CSE, U.I.E.T, M.D.U. Rohtak -124001 (INDIA) Abstract Security is a crucial service in wireless sensor networks that is becoming increasingly common in WSNs because wireless sensor nodes are typically deployed in an unattended environment, leaving them open to possible hostile network attack. Because wireless sensor nodes are limited in computing power, data storage and communication capabilities, any user authentication protocol must be designed to operate efficiently in a resource constrained environment. With a widespread growth in the potential applications of WSN, the need for reliable security mechanisms for them has increased manifold. Security protocols in WSNs, unlike the traditional mechanisms, need special efforts and issues to be addressed. The set of challenges in sensor networks are diverse, we focus on attacks on Wireless Sensor Network in this paper. Keywords: Wireless Sensor Network, WSN, Security, Attacks. 1. Introduction Wireless Sensor Networks (WSN) consist of small Devices—called sensor nodes—with RF radio, processor, memory, battery and sensor hardware. We use the term sensor network to refer to a heterogeneous system combining tiny sensors and actuators with general purpose computing elements. One can precisely monitor the environment with widespread deployment of these devices. Sensor nodes are resource-constrained in terms of the RF radio range, processor speed, memory size and power. Apart from this, sensor nodes are generally stationary. The traffic rate is very low and traffic is periodic as well. There may be long idle periods during which sensor nodes turn off their radio to save energy consumed by idle listening. Recharging or replacing batteries is expensive and may not even be feasible in some situations. Therefore, WSN applications need to be extremely energy-aware. WSNs are mostly unguarded. Hence capturing a node physically, altering its code and getting private information like cryptographic keys is easily possible for an attacker. Wireless medium is inherently broadcast in nature. This makes them vulnerable to attacks. These attacks can disrupt the operation of WSN and can even defeat the purpose of their deployment. An adversary can launch DoS attacks without much effort (e.g. even without cracking keys used for cryptography-based solutions). The Application domain of Wireless Sensor Network is diverse due to the availability of micro- sensors and low-power wireless communications. Unlike the traditional sensors, in the remote sensor network, a vast numbers of sensors are densely deployed. These sensor nodes will perform significant signal processing, computation, and network self- configuration to achieve scalable, robust and long-lived networks [3]. WSN’s unique features, sensor networks are used in wide range of applications in areas like health, military, home and commercial industries in our day to day life [4] [5] [6]. In the near future, this wide range of application areas will make sensor networks an integral part of life [7]. WSN technology enables monitoring of vast and remote geographical region, in such a way that abnormal events can be quickly detected. The cost of sensor nodes varies from hundreds of dollars to a few cents, depending upon their size and complexity. Size and cost constraints on sensor nodes result in corresponding constraints on resources such as energy, memory, computational speed and transmission range [8].