Ismail Butun

A Survey of Intrusion Detection Systems in Wireless Sensor Networks

Wireless Sensor Networking is one of the most promising technologies that have applications ranging from health care to tactical military. Although Wireless Sensor Networks (WSNs) have appealing features (e.g., low installation cost, unattended network operation), due to the lack of a physical line of defense (i.e., there are no gateways or switches to monitor the information flow), the security of such networks is a big concern, especially for the applications where confidentiality has prime importance. Therefore, in order to operate WSNs in a secure way, any kind of intrusions should be detected before attackers can harm the network (i.e., sensor nodes) and/or information destination (i.e., data sink or base station). In this article, a survey of the state-of-the-art in Intrusion Detection Systems (IDSs) that are proposed for WSNs is presented. Firstly, detailed information about IDSs is provided. Secondly, a brief survey of IDSs proposed for Mobile Ad-Hoc Networks (MANETs) is presented and applicability of those systems to WSNs are discussed. Thirdly, IDSs proposed for WSNs are presented. This is followed by the analysis and comparison of each scheme along with their advantages and disadvantages. Finally, guidelines on IDSs that are potentially applicable to WSNs are provided. Our survey is concluded by highlighting open research issues in the field.

An energy-efficient access control scheme for wireless sensor networks based on elliptic curve cryptography

For many mission-critical related wireless sensor network applications such as military and homeland security, users access restriction is necessary to be enforced by access control mechanisms for different access rights. Public key-based access control schemes are more attractive than symmetric-key based approaches due to high scalability, low memory requirement, easy key-addition/revocation for a new node, and no key pre-distribution requirement. Although Wang et al. recently introduced a promising access control scheme based on elliptic curve cryptography (ECC), it is still burdensome for sensors and has several security limitations (it does not provide mutual authentication and is strictly vulnerable to denial-of-service (DoS) attacks). This paper presents an energy-efficient access control scheme based on ECC to overcome these problems and more importantly to provide dominant energy-efficiency. Through analysis and simulation based evaluations, we show that the proposed scheme overcomes the security problems and has far better energy-efficiency compared to current scheme proposed by Wang et al.

Impact of mobility prediction on the performance of Cognitive Radio networks

Wireless technology has enabled the development of increasingly diverse applications and devices resulting in an exponential growth in usage and services. These advancements made the radio frequency spectrum a scarce resource, and consequently, its efficient use is of the ultimate importance. To cope with the growing demand, network design focused on increasing the spectral efficiency by making use of advancement in Cognitive Radio technology. Cognitive Radio can reduce the spectrum shortage problem by enabling unlicensed users equipped with Cognitive Radios to reuse and share the licensed spectrum bands. Using the fact that a Cognitive Radio is capable of sensing the environmental conditions and automatically adapting its operating parameters in order to enhance network performance, we would like to make use of its knowledge to predict the mobility of Cognitive Radio users to improve the overall performance of the Cognitive Radio network. This study makes novel use of mobility prediction techniques to enhance reliability, bandwidth efficiency and scalability of the cognitive radio networks. Firstly, prediction techniques are evaluated and compared for prediction accuracy. Secondly, routing protocol reliability, efficiency and scalability performances are evaluated under different prediction techniques. Simulation results verify the performance improvements even with moderate accuracy predictors. Results clearly show that hybrid Markov CDF prediction performs the best. When compared with no prediction it significantly improves average reliability and efficiency by 11% and 8%, respectively.

A brief survey of access control in Wireless Sensor Networks

In this paper, we investigate applications of access control to Wireless Sensor Networks (WSNs). Although access control was well established for traditional computer systems, it has not been studied thoroughly in WSN environments. We briefly provide the WSN specifications and then stress the constraints of the WSNs that would affect the access control implementation. We also provide a literature overview and discuss further possible solutions.

Intrusion prevention with two-level user authentication in heterogeneous wireless sensor networks

In this paper, we propose a secure and scalable user authentication scheme for heterogeneous wireless sensor networks to prevent intrusions. Our scheme employs both public and secret key cryptography schemes, such that it takes advantages from both. Our analysis and simulation results show that our scheme is not only more secure and scalable than existing secret key cryptography-based schemes, but also requires less processing power and provides higher energy efficiency than existing public key cryptography-based schemes.

Advanced two tier User Authentication scheme for heterogeneous Wireless Sensor Networks

In this paper, we propose a novel User Authentication (UA) scheme for heterogeneous Wireless Sensor Networks (WSNs), which employs both Public Key Cryptography (PKC) and Symmetric Key Cryptography (SKC) approaches, such that it takes advantage of both schemes. Our analysis results have shown that, our scheme is not only more secure and scalable than existing SKC based schemes, but also requires lesser processing power and provides higher energy efficiency than existing PKC based schemes.

Coherence time-based cooperative MAC protocol 1 for wireless ad hoc networks

In this article, we address the goal of achieving performance gains under heavy-load and fast fading conditions. CoopMACI protocol proposed in Proceedings of the IEEE International Conference on Communications (ICC), Seoul, Korea, picks either direct path or relay path based on rate comparison to enhance average throughput and delay performances. However, CoopMACI performance deteriorates under fading conditions because of lower direct path or relay path reliability compared to UtdMAC (Agarwal et al. LNCS, 4479, 415-426, 2007). UtdMAC was shown to perform better than CoopMACI in terms of average throughput and delay performances because of improved transmission reliability provided by the backup relay path. Although better than CoopMACI, UtdMAC does not fully benefit from higher throughput relay path (compared to the direct path), since it uses relay path only as a secondary backup path. In this article, we develop a cooperative MAC protocol (termed as instantaneous relay-based cooperative MAC--IrcMAC) that uses channel coherence time and estimates signal-to-noise ratio (SNR) of source-to-relay, relay-to-destination, and source-to-destination links, to reliably choose between relay path or direct path for enhanced throughput and delay performances. Unique handshaking is used to estimate SNR and single bit feedbacks resolve contentions among relay nodes, which further provides source node with rate (based on SNR) information on source-to-destination, source-to-relay, and relay-to-destination links. Simulation results clearly show that IrcMAC significantly outperforms the existing CoopMACI and the UtdMAC protocols in wireless ad hoc network. Results show average throughput improvements of 41% and 64% and average delay improvementd of 98.5% and 99.7% compared with UtdMAC and CoopMACI, respectively.

An Intrusion Detection System Based on Multi-Level Clustering for Hierarchical Wireless Sensor Networks.

In this work, an intrusion detection system (IDS) framework based on multi-level clustering for hierarchical wireless sensor networks is proposed. The framework employs two types of intrusion detection approaches: (1) “downward-IDS (D-IDS)” to detect the abnormal behavior (intrusion) of the subordinate (member) nodes; and (2) “upward-IDS (U-IDS)” to detect the abnormal behavior of the cluster heads. By using analytical calculations, the optimum parameters for the D-IDS (number of maximum hops) and U-IDS (monitoring group size) of the framework are evaluated and presented.

Evaluation of Advanced Two Tier User Authentication scheme

In this paper, we evaluate the performance of our Advanced Two Tier User Authentication (ATTUA) scheme [5] which is proposed for heterogeneous Wireless Sensor Networks. ATTUA scheme employs both Public Key Cryptography (PKC) and Secret Key Cryptography (SKC) approaches, such that it takes advantage of both schemes. Our analysis and simulation results have shown that, ATTUA scheme is not only more secure and yet scalable than existing SKC based schemes, but also requires less processing power and provides higher energy efficiency than existing PKC based schemes.

Performance Evaluation of Quick-Start in Low Latency Networks

The Quick-Start mechanism has been presented as a way for transport control protocols to efficiently use available bandwidth in under-utilized networks. Although studies of performance of Quick-Start have been carried out, its performance in low latency networks has not been well investigated. In this paper, we show that the benefits of Quick-Start in low latency networks are minimal. We also show that the improvement in network utilization is much lower than in networks with higher latencies. Our future work in this field will undoubtedly lead to new algorithms and improvements to existing ones.