Design and Development of an Efficient Cryptographic Algorithm for Wireless Sensor Networks

Abstract

The need of security in any application becomes vital when two parties want to communicate through insecure channel in presence of some unfaithful third party (adversary). The adversary may capture sensitive information during transmission through active or passive attacks. Due to its resource-constrained nature, security in embedded devices is of great concern and needs to be addressed seriously. A Wireless Sensor Network (WSN) is a collection of massive number of sensor nodes with limited computing power, storage, battery but is still able to communicate so that information gathered from the physical environment by individual sensor node, can reach the base station (a powerful device - may be a laptop). Recent advances in WSN have led to several new promising applications, including forest re detection, target tracking in military applications, healthiness of humans, health monitoring of civil structures and forecasting of natural disasters to name a few. In a WSN, sensor nodes are not temper resistant and the communication mode is wireless, therefore, it is extremely vulnerable to various types of attacks. These attacks may be of stealing the information from the sensor node physically or it may be a case of eavesdropping during transmission of gathered information. To protect the transmitted information, medium of transmission should be secured as well as the message should be in some unreadable form. Cryptography is widely used to provide the secure data transmission and also lend some computation as well as communication overheads. The contributions of this thesis to the area of cryptography are manifold. Firstly, a historical perspective and brief introduction of the area are presented. It includes the overview of WSN, security requirement for WSN, measures of security and security solutions based on cryptography. Also, a literature review of speci fically designed and implemented cryptographic frameworks for WSN is presented. Secondly, we provide the preliminary concepts of cryptography like Elliptic Curve Cryptography (ECC), bilinear pairing, computational hardness problems, formal models of signature and signcryption algorithms and their security models. Also, we present the simulation and experimental setup for the implementation of the proposed work. It includes an overview of the motes, TinyOS operating system for the MICAz mote, RELIC cryptographic library, and the AVRORA simulator. Thirdly, we propose two signature schemes for WSN, one is based on Identity-Based Cryptography and the other is based on Certi cateLess Cryptography. The former The need of security in any application becomes vital when two parties want to communicate through insecure channel in presence of some unfaithful third party (adversary). The adversary may capture sensitive information during transmission through active or passive attacks. Due to its resource-constrained nature, security in embedded devices is of great concern and needs to be addressed seriously.

A Wireless Sensor Network (WSN) is a collection of massive number of sensor nodes with limited computing power, storage, battery but is still able to communicate so that information gathered from the physical environment by individual sensor node, can reach the base station (a powerful device - may be a laptop). Recent advances in WSN have led to several new promising applications, including forest fire detection, target tracking in military applications, healthiness of humans, health monitoring of civil structures and forecasting of natural disasters to name a few.

In a WSN, sensor nodes are not temper resistant and the communication mode is wireless, therefore, it is extremely vulnerable to various types of attacks. These attacks may be of stealing the information from the sensor node physically or it may be a case of eavesdropping during transmission of gathered information. To protect the transmitted information, medium of transmission should be secured as well as the message should be in some unreadable form. Cryptography is widely used to provide the secure data transmission and also lend some computation as well as communication overheads.

The contributions of this thesis to the area of cryptography are manifold. Firstly, a historical perspective and brief introduction of the area are presented. It includes the overview of WSN, security requirement for WSN, measures of security and security solutions based on cryptography. Also, a literature review of specifically designed and implemented cryptographic frameworks for WSN is presented.

Secondly, we provide the preliminary concepts of cryptography like Elliptic Curve Cryptography (ECC), bilinear pairing, computational hardness problems, formal models of signature and signcryption algorithms and their security models. Also, we present the simulation and experimental setup for the implementation of the proposed work. It includes an overview of the motes, TinyOS operating system for the MICAz mote, RELIC cryptographic library, and the AVRORA simulator.

Thirdly, we propose two signature schemes for WSN, one is based on Identity-Based Cryptography and the other is based on CertificateLess Cryptography. The former signature scheme is based on Elliptic Curve Discrete Logarithm Problem (ECDLP).

The major benefit of this scheme is evading the use of bilinear pairing and the latter signature scheme is based on RSA. In order to evaluate the performance of the proposed schemes for WSN, the parameters used are running time, energy consumption and memory consumption. Further, cryptanalysis of three certificateless signature schemes against malicious-user and/or malicious-KGC-attack is presented. In addition, a novel insight to extend certificateless authentication to WSN has also been proposed. The analysis is encouraging as the computation cost reduced by more than 50 percent.

Fourthly, we also propose two ring signcryption schemes based on (Identity-Based and CertificateLess) for WSN. Further, the proposed Identity-based Ring SignCryption (IRSC) scheme has been compared with all existing ring signcryption schemes and proved to be superior. Also, a novel efficient CertificateLess Ring SignCryption scheme has been proposed, which eliminates bilinear pairing operation. The computation overhead has also been measured by counting the number of basic operations like point addition on a group, scalar multiplication on a group, pairing operation, XOR operation, hash operation, ciphertext size, which are helpful in deciding the efficiency of the algorithm. The implementation part has been performed using MICAz mote, mainly focusing on parameters: storage (bytes), running time (s) and energy consumption (mJ) during signcryption and unsigncryption.

Finally, we conclude with the contributions made in the thesis and suggest some outline for future work. proposed schemes for WSN, the parameters used are running time, energy consump- tion and memory consumption. Further, cryptanalysis of three certi cateless signature schemes against malicious-user and/or malicious-KGC-attack is presented. In addition, a novel insight to extend certi cateless authentication to WSN has also been proposed. The analysis is encouraging as the computation cost reduced by more than 50 percent. Fourthly, we also propose two ring signcryption schemes based on (Identity-Based and Certi cateLess) for WSN. Further, the proposed Identity-based Ring SignCryption (IRSC) scheme has been compared with all existing ring signcryption schemes and proved to be superior. Also, a novel e cient Certi cateLess Ring SignCryption scheme has been proposed, which eliminates bilinear pairing operation. The computation overhead has also been measured by counting the number of basic operations like point addition on a group, scalar multiplication on a group, pairing operation, XOR operation, hash operation, ciphertext size, which are helpful in deciding the e ciency of the algorithm. The implementation part has been performed using MICAz mote, mainly focusing on parameters: storage (bytes), running time (s) and energy consumption (mJ) during signcryption and unsigncryption. Finally, we conclude with the contributions made in the thesis and suggest some outline for future work.