Practical implementation and performance analysis on security of sensor networks

A wireless sensor network (WSN) is a network made of thousands of sensing elements called as nodes with wireless capabilities. Their application is varied and diverse ranging from military to domestic and household. As the world of self-organizing sensor networks tip to the edge of maximum utilization, their wider deployment is adding pressure on the security front. Powerful laptops and workstations make it more challenging for small sensors. In addition, there are many security challenges in WSN, e.g- confidentiality, authentication, freshness, integrity etc. Contributions of this work are as follows: “Symmetric” security implementation: This thesis work designs a symmetric-key based security in sensor hardware in the Link layer of sensor network protocols. Link Layer security can protect a wireless network by denying access to the network itself before a user is successfully authenticated. This prevents attacks against the network infrastructure and protects the network from devastating attacks. “Public key” implementation in sensor hardware: Asymmetric key techniques are attractive for authentication data or session keys. Traditional schemes like RSA require considerable amounts of resources which in the past has limited their use. This thesis has implemented Elliptic Curve Cryptography (ECC) in Mica2 hardware, which is an approach to public-key cryptography based on the mathematics of elliptic curves. Quantitative overhead analysis: This thesis work analyzes the wireless communication overhead (No. of packets transmitted) vs the (transmit and receive) energy consumed in mJoules and memory storage overhead (bytes) for ECC as compared to the symmetric counterpart for the implemented WSN security protocols

Public key cryptography in resource-constrained WSN

In this paper we present a detailed review of the works on public key cryptography (PKC) in wireless sensor networks (WSNs). In the early days of sensor networks, public key cryptography was thought to be completely unfeasible considering its computational complexity and energy requirements. By this time, several works have proved that the lightweight versions of many well-known public key algorithms can be utilized in WSN environment. With the expense of a little energy, public key based schemes could in fact be the best choice for ensuring data security in high-security demanding WSN applications. Here, we talk about the notion of public key cryptography in WSN, its applicability, challenges in its implementation, and present a detailed study of the significant works on PKC in WSN

Cryptographic Key Distribution In Wireless Sensor Networks Using Bilinear Pairings

It is envisaged that the use of cheap and tiny wireless sensors will soon bring a third wave of evolution in computing systems. Billions of wireless senor nodes will provide a bridge between information systems and the physical world. Wireless nodes deployed around the globe will monitor the surrounding environment as well as gather information about the people therein. It is clear that this revolution will put security solutions to a great test. Wireless Sensor Networks (WSNs) are a challenging environment for applying security services. They differ in many aspects from traditional fixed networks, and standard cryptographic solutions cannot be used in this application space. Despite many research efforts, key distribution in WSNs still remains an open problem. Many of the proposed schemes suffer from high communication overhead and storage costs, low scalability and poor resilience against different types of attacks. The exclusive usage of simple and energy efficient symmetric cryptography primitives does not solve the security problem. On the other hand a full public key infrastructure which uses asymmetric techniques, digital signatures and certificate authorities seems to be far too complex for a constrained WSN environment. This thesis investigates a new approach to WSN security which addresses many of the shortcomings of existing mechanisms. It presents a detailed description on how to provide practical Public Key Cryptography solutions for wireless sensor networks. The contributions to the state-of-the-art are added on all levels of development beginning with the basic arithmetic operations and finishing with complete security protocols. This work includes a survey of different key distribution protocols that have been developed for WSNs, with an evaluation of their limitations. It also proposes Identity- Based Cryptography (IBC) as an ideal technique for key distribution in sensor networks. It presents the first in-depth study of the application and implementation of Pairing- Based Cryptography (PBC) to WSNs. This is followed by a presentation of the state of the art on the software implementation of Elliptic Curve Cryptography (ECC) on typical WSNplatforms. New optimized algorithms for performing multiprecision multiplication on a broad range of low-end CPUs are introduced as well. Three novel protocols for key distribution are proposed in this thesis. Two of these are intended for non-interactive key exchange in flat and clustered networks respectively. A third key distribution protocol uses Identity-Based Encryption (IBE) to secure communication within a heterogeneous sensor network. This thesis includes also a comprehensive security evaluation that shows that proposed schemes are resistant to various attacks that are specific to WSNs. This work shows that by using the newest achievements in cryptography like pairings and IBC it is possible to deliver affordable public-key cryptographic solutions and to apply a sufficient level of security for the most demanding WSN applications

An Implementation of Digital Signature and Key Agreement on IEEE802.15.4 WSN Embedded Device

A wireless sensor network (WSN) now becomes popular in context awareness development to distribute critical information and provide knowledge services to everyone at anytime and anywhere. However, the data transfer in a WSN potentially encounters many threats and attacks. Hence, particular security schemes are required to prevent them. A WSN usually uses low power, low performance, and limited resources devices. One of the most promising alternatives to public key cryptosystems is Elliptic Curve Cryptography (ECC), due to it pledges smaller keys size. This implies the low cost consumption to calculate arithmetic operations in cryptographic schemes and protocols. Therefore, ECC would be strongly required to be implemented in WSN embedded devices with limited resources (i.e., processor speed, memory, and storage). In this paper, we present an implementation of security system on IEEE802.15.4 WSN device with the employment of Elliptic Curve Digital Signature Algorithm (ECDSA) and Elliptic Curve Diffie-Hellman (ECDH) key exchange protocol. Our experimental results on Intel Mote2 showed that the total time for signature generation is 110 ms, signature verification is 134 ms, and ECDH shared key generation is 69 ms on the setting of 160-bit security level

Unified Compact ECC-AES Co-Processor with Group-Key Support for IoT Devices in Wireless Sensor Networks

Security is a critical challenge for the effective expansion of all new emerging applications in the Internet of Things paradigm. Therefore, it is necessary to define and implement different mechanisms for guaranteeing security and privacy of data interchanged within the multiple wireless sensor networks being part of the Internet of Things. However, in this context, low power and low area are required, limiting the resources available for security and thus hindering the implementation of adequate security protocols. Group keys can save resources and communications bandwidth, but should be combined with public key cryptography to be really secure. In this paper, a compact and unified co-processor for enabling Elliptic Curve Cryptography along to Advanced Encryption Standard with low area requirements and Group-Key support is presented. The designed co-processor allows securing wireless sensor networks with independence of the communications protocols used. With an area occupancy of only 2101 LUTs over Spartan 6 devices from Xilinx, it requires 15% less area while achieving near 490% better performance when compared to cryptoprocessors with similar features in the literature

A Lightweight Policy System for Body Sensor Networks

Body sensor networks (BSNs) for healthcare have more stringent security and context adaptation requirements than required in large-scale sensor networks for environment monitoring. Policy-based management enables flexible adaptive behavior by supporting dynamic loading, enabling and disabling of policies without shutting down nodes. This overcomes many of the limitations of sensor operating systems, such as TinyOS, which do not support dynamic modification of code. Alternative schemes for adaptation, such as network programming, have a high communication cost and suffer from operational interruption. In addition, a policy-driven approach enables finegrained access control through specifying authorization policies. This paper presents the design, implementation and evaluation of an efficient policy system called Finger which enables policy interpretation and enforcement on distributed sensors to support sensor level adaptation and fine-grained access control. It features support for dynamic management of policies, minimization of resources usage, high responsiveness and node autonomy. The policy system is integrated as a TinyOS component, exposing simple, well-defined interfaces which can easily be used by application developers. The system performance in terms of processing latency and resource usage is evaluated. © 2009 IEEE.Published versio

Secure Platform Over Wireless Sensor Networks

Life sciences: general issue