A survey of security issues in wireless sensor networks <s> NETWORK AND ROUTING LAYER <s> As sensor networks edge closer towards wide-spread deployment, security issues become a central concern. So far, much research has focused on making sensor networks feasible and useful, and has not concentrated on security. We present a suite of security building blocks optimized for resource-constrained environments and wireless communication. SPINS has two secure building blocks: SNEP and μTESLA SNEP provides the following important baseline security primitives: Data confidentiality, two-party data authentication, and data freshness. A particularly hard problem is to provide efficient broadcast authentication, which is an important mechanism for sensor networks. μTESLA is a new protocol which provides authenticated broadcast for severely resource-constrained environments. We implemented the above protocols, and show that they are practical even on minimal hardware: the performance of the protocol suite easily matches the data rate of our network. Additionally, we demonstrate that the suite can be used for building higher level protocols. <s> BIB001 </s> A survey of security issues in wireless sensor networks <s> NETWORK AND ROUTING LAYER <s> We consider routing security in wireless sensor networks. Many sensor network routing protocols have been proposed, but none of them have been designed with security as a goal. We propose security goals for routing in sensor networks, show how attacks against ad-hoc and peer-to-peer networks can be adapted into powerful attacks against sensor networks, introduce two classes of novel attacks against sensor networks sinkholes and HELLO floods, and analyze the security of all the major sensor network routing protocols. We describe crippling attacks against all of them and suggest countermeasures and design considerations. This is the first such analysis of secure routing in sensor networks. <s> BIB002 </s> A survey of security issues in wireless sensor networks <s> NETWORK AND ROUTING LAYER <s> As mobile ad hoc network applications are deployed, security emerges as a central requirement. In this paper, we introduce the wormhole attack, a severe attack in ad hoc networks that is particularly challenging to defend against. The wormhole attack is possible even if the attacker has not compromised any hosts, and even if all communication provides authenticity and confidentiality. In the wormhole attack, an attacker records packets (or bits) at one location in the network, tunnels them (possibly selectively) to another location, and retransmits them there into the network. The wormhole attack can form a serious threat in wireless networks, especially against many ad hoc network routing protocols and location-based wireless security systems. For example, most existing ad hoc network routing protocols, without some mechanism to defend against the wormhole attack, would be unable to find routes longer than one or two hops, severely disrupting communication. We present a new, general mechanism, called packet leashes, for detecting and thus defending against wormhole attacks, and we present a specific protocol, called TIK, that implements leashes. <s> BIB003 </s> A survey of security issues in wireless sensor networks <s> NETWORK AND ROUTING LAYER <s> Security is important for many sensor network applications. A particularly harmful attack against sensor and ad hoc networks is known as the Sybil attack based on J.R. Douceur (2002), where a node illegitimately claims multiple identities. This paper systematically analyzes the threat posed by the Sybil attack to wireless sensor networks. We demonstrate that the attack can be exceedingly detrimental to many important functions of the sensor network such as routing, resource allocation, misbehavior detection, etc. We establish a classification of different types of the Sybil attack, which enables us to better understand the threats posed by each type, and better design countermeasures against each type. We then propose several novel techniques to defend against the Sybil attack, and analyze their effectiveness quantitatively. <s> BIB004
The network and routing layer of sensor networks is usually designed according to the following principles  : • Power efficiency is an important consideration. • Sensor networks are mostly data-centric. • An ideal sensor network has attribute-based addressing and location awareness. The attacks in the network and the routing layer include the following. Spoofed, Altered, or Replayed Routing InformationThe most direct attack against a routing protocol in any network is to target the routing information itself while it is being exchanged between nodes. An attacker may spoof, alter, or replay routing information in order to disrupt traffic in the network BIB002 . These disruptions include the creation of routing loops, attracting or repelling network traffic from select nodes, extending and shortening source routes, generating fake error messages, partitioning the network, and increasing end-to-end latency. A countermeasure against spoofing and alteration is to append a message authentication code (MAC) after the message. By adding a MAC to the message, the receivers can verify whether the messages have been spoofed or altered. To defend against replayed information, counters or timestamps can be included in the messages BIB001 . Selective Forwarding -A significant assumption made in multihop networks is that all nodes in the network will accurately forward received messages. An attacker may create malicious nodes which selectively forward only certain messages and simply drop others BIB002 . A specific form of this attack is the black hole attack in which a node drops all messages it receives. One defense against selective forwarding attacks is using multiple paths to send data BIB002 . A second defense is to detect the malicious node or assume it has failed and seek an alternative route. Sinkhole -In a sinkhole attack, an attacker makes a compromised node look more attractive to surrounding nodes by forging routing information [5, BIB002 . The end result is that surrounding nodes will choose the compromised node as the next node to route their data through. This type of attack makes selective forwarding very simple, as all traffic from a large area in the network will flow through the adversary's node. Sybil -The Sybil attack is a case where one node presents more than one identity to the network  BIB002 BIB004 . Protocols and algorithms which are easily affected include fault-tolerant schemes, distributed storage, and network-topology maintenance. For example, a distributed storage scheme may rely on there being three replicas of the same data to achieve a given level of redundancy. If a compromised node pretends to be two of the three nodes, the algorithms used may conclude that redundancy has been achieved while in reality it has not. Wormholes -A wormhole is a low-latency link between two portions of the network over which an attacker replays network messages BIB002 . This link may be established either by a single node forwarding messages between two adjacent but otherwise non-neighboring nodes or by a pair of nodes in different parts of the network communicating with each other. The latter case is closely related to the sinkhole attack, as an attacking node near the base station can provide a one-hop link to that base station via the other attacking node in a distant part of the network. Hu et al. presented a novel and general mechanism called packet leashes for detecting and defending against wormhole attacks BIB003 . Two types of leashes were introduced: geographic leashes and temporal leashes. The proposed mechanisms can also be used in WSNs. Hello Flood Attacks -Many protocols which use HELLO packets make the naive assumption that receiving such a packet means the sender is within radio range and is therefore a neighbor. An attacker may use a high-powered transmitter to trick a large area of nodes into believing they are neighbors of that transmitting node BIB002 . If the attacker falsely broadcasts a superior route to the base station, all of these nodes will attempt transmission to the attacking node, despite many being out of radio range in reality. Acknowledgment Spoofing -Routing algorithms used in sensor networks sometimes require Acknowledgments to be used. An attacking node can spoof the Acknowledgments of overheard packets destined for neighboring nodes in order to provide false information to those neighboring nodes BIB002 . An example of such false information is claiming that a node is alive when in fact it is dead.