International Journal of Computer Applications (0975 – 8887) Volume 78 – No.11, September 2013 23 Analysis of Detection of Multiple Attackers in Wireless Networks Pornima K.Girwalkar PG Student M.B.E.S’s College of Engineering, Ambajogai Maharashtra B.M. Patil Professor M.B.E.S’s College of Engineering, Ambajogai Maharashtra ABSTRACT Wireless networks are usually deployed in hostile environment where an adversary can masquerade some internal nodes which may launch various inside attacks which may leads to reduction in network performance. Although the identity of a node can be verified through cryptographic authentication, conventional security approaches are not always desirable because of their overhead requirements. In this paper one method is used based on spatial correlation of Received signal strength of each node to find out the presence of attack and a cluster based mechanism is used to find out number of attackers. An efficiency based RADAR gridded algorithm is used further to localize the no of attackers in the network. Experimental evaluation is carried out using two test simulations of IEEE 802.11 and Zigbee networks. The comparison shows that the packet overheads are lesser as compared to other schemes. It has been observed that packet delivery ratio and end to end delay increases as increase number of nodes while energy decreases with optimal point. Keywords Wireless Network Security, Attack Detection, RSS value, Localization etc. 1. INTRODUCTION We ask that Wireless networks have displaced the well established and widely deployed wired communication networks of the past. Also, the reliability of wireless communication has improved significantly and is reflected in its application to areas such as police radio, military communication, and disaster recovery services. This reliability is not only reflected in such public safety applications, but also in many civilian applications [1]. Similarly, it is common to carry out a secure transaction over the Internet through a wireless local area network (WLAN). WLAN deployments based upon IEEE 802.11 standard are planned in many metropolitan areas. ZigBee Network is based on an IEEE 802.15.4 standard. Though low-powered, ZigBee devices often transmit data over longer distances by passing data through intermediate devices to reach more distant ones, i.e., a network with no centralized control or high-power transmitter/receiver able to reach all of the networked devices. The decentralized nature of such wireless ad-hoc networks make them suitable for applications where a central node can't be relied upon. The explosive growth of 802.11b networks has coincided with an increased presence of security threats to these networks. A large proportion of these threats are in the form of spoof attacks or wormhole attacks. Due to the identity masquerading, Wireless networks are susceptible to the different types of network attacks. However, this same ease of access and mobility can also be leveraged by malicious individuals to attack from the most unlikely of locations. Attacks on a wireless network can come from all directions and target at any node. Damages can include leaking secret information, message contamination, and node impersonation, sniff sensitive information, and access the internal network or attack wireless hosts without direct access to the network. All these mean that a wireless network will not have a clear line of defense, and every node must be prepared for encounters with an adversary directly or indirectly. Along with these issues, a wireless network has several special requirements that raise novel technical challenges such as network size, power constraints and energy consumption by nodes. However, there is no perfect approach which has yet proven to be robust against all attacks. They can be combined to create more complex forms of attacks by flooding, packet dropping or manipulating nodes in the network. In the rest of this paper, we focus on the problem of detecting attacks on wireless networks. Attack Determination and localization can be done by various techniques. Many different types of approaches are available for security of network applications, some focus on energy saving, resource awareness or in-built security mechanisms. Cryptographic methods provide the strategic prevention and detection of attackers on account of identification and confidentiality of the network nodes. 2. RELATED WORK There are many approaches regarding wireless network security. The existing 802.11 security techniques such as including Wired Equivalent Privacy (WEP), WiFi Protected Access (WPA), or 802.11i (WPA2), these methodologies only protect data frames. But an attacker can still spoof management or control frames to cause significant impact on networks [2]. Traditionally cryptographic techniques are used for secure communications in wired and wireless networks. The asymmetric cryptography is widely used because it has the significant features like authentication, integrity, and confidentiality and simplicity for key distribution. With regards to the cryptographic approach, Bing, Jie and Eduardo [3] have proposed one approach which is the centralized framework of public key infrastructure (PKI).By applying a secret and secure sharing scheme and an underlying multicast server group, a PKI is build. And after in SEKM, a view of the certification authority (CA) is created by the server group, which provides certificate update service for all nodes, including the servers themselves. In that a ticket scheme is introduced for efficient certificate service. By Bohge and Trappe [4] have presented a new type of certificate, called a TESLA certificate that can be used by low-powered nodes to perform entity authentication. The framework authenticates incoming nodes, maintains trust