PhD Research Work
Thesis Title: Design and Analysis of Key Distribution Mechanisms in Wireless Sensor Networks (Download Thesis)
Duration: January 2004 - June 2008
Supervisor(s):
1) Dr. Abhijit Das
Department of Computer Science and Engineering
Indian Institute of Technology, Kharagpur 721 302, INDIA
2) Prof. Indranil Sen Gupta
Department of Computer Science and Engineering
Indian Institute of Technology, Kharagpur 721 302, INDIA
External Examiner(s):
1) Prof. Sushil Jajodia
IEEE Life Fellow
University Professor, BDM International
Professor of Information Technology, and Director
Center for Secure Information Systems
Volgenau School of Engineering
George Mason University Fairfax, USA
Homepage: http://csis.gmu.edu/jajodia/
2) Prof. G. Sivakumar
Department of Computer Science and Engineering
Indian Institute of Technology, Bombay, INDIA
Homepage: http://www.cse.iitb.ac.in/~siva/
Abstract:
Due to resource limitations as well as vulnerability to physical capture of sensor nodes, traditional public key security protocols (e.g., RSA, Diffie-Hellman key exchange, Elliptic Curve Cryptography (ECC), ElGamal cryptosystem, etc.) are too complicated and energy-consuming for large-scale wireless sensor networks. As a result, symmetric ciphers such as DES, IDEA, RC5, AES are the viable options for encryption/decryption of secret data. In order to establish symmetric secret keys between communicating sensor nodes in a sensor network, we typically use the bootstrapping protocol. This protocol establishes cryptographically secure communication links among the communicating sensor nodes. However, this is a challenging area of research due to resource limitations and physical insecurity of sensor nodes.
Since wireless sensor networks are often operated in an unattended mode, an adversary may physically capture some sensors to compromise their stored sensitive data as well as communication secret keys. Therefore, any adversary that gets hold of a sensor node can easily extract its stored cryptographic information. These features and challenges motivate the research on development of secure key distribution mechanisms for wireless sensor networks.
In this thesis, secure key distribution mechanisms are studied. The first study is based on improvements of the path key establishment phase of the bootstrapping protocol in static wireless sensor networks. We have developed two location-adaptive key establishment schemes, namely, the key forwarding scheme and the multi-hop key forwarding scheme which achieve significantly better network performances as well as security against node capture as compared to those for the path key establishment.
The second study is devoted on the identity-based random key distribution mechanism in static wireless sensor networks. We have proposed a technique to achieve this goal. The proposed technique provides better network performances and security against node capture as compared to those for the existing schemes.
The third study investigates how to improve performances of the existing location-aware key distribution schemes in static wireless sensor networks. We have designed the location-aware t-neighborhood scheme based on pre-deployment knowledge of sensor nodes in a target field, which achieves better performance as compared to those for the existing location-aware key distribution schemes. We have then proposed another location-aware scheme, called the enhanced closest pairwise keys scheme (ECPKS), based on both pre-deployment and post-deployment knowledge of sensor nodes. ECPKS provides better performances as compared to those for the existing location-aware key distribution schemes even if the maximum deployment error between the actual location and the expected location of sensor nodes is larger.
The last study focuses on key distribution mechanisms with the help of high-end auxiliary nodes in static heterogeneous wireless sensor networks. For this purpose, we have proposed a naive key distribution technique for heterogeneous wireless sensor networks. Through analysis and simulation results, we have claimed that the network performances of our proposed scheme are much better as compared to those for the existing key pre-distribution schemes.
Keywords: Wireless sensor networks, Location-adaptive key distribution, Identity-based random key distribution, Location-aware key distribution, Static sensor networks, Key pre-distribution, Direct key establishment, Path key establishment, Network connectivity, Security.