Efficient Key Generation for Dynamic Blom's Scheme

The need for secure communication between the nodes in a network has led to the development of various key distribution schemes. Blom’s scheme is a prominent key exchange protocol used for sensor and wireless networks, but its shortcomings include large computation overhead and memory cost. In this paper, we propose an efficient key management scheme by generating new public and private keys. We also focus on making Blom’s scheme dynamic by randomly changing the secret key that is generated by the base station and we propose the use of the mesh array for matrix multiplication for reducing the computation overhead. INTRODUCTION Recent improvements in the field of electronic and computer technologies, have paved the way for the proliferation of wireless sensor networks (WSN).These sensors are used to collect environmental information and they have been considered for various purposes, including security monitoring, target tracking and research activities in hazardous environments. Encryption, authentication, confidentiality and key management are the main aspects to focus on to achieve security in wireless sensor networks. Different key management schemes have been developed for authentication and confidentiality purposes. Symmetric algorithm base key management protocols are used in wireless sensor networks because key management protocols based on public key cryptography are inefficient due to resource limitations. Blom’s scheme [1] and others related to it [2]-[10] to it are often used for secure sensor communication. Issues that need to be considered include key management [13]-[17] and randomness of sequences [18]-[23]. In this paper we review general considerations and then propose our scheme for dynamic change of keys. We present results of our simulations. GENERAL CONSIDERATIONS The main challenges of the sensor nodes are as follows:  The nodes are solely responsible for any change in the configuration as there would be no human intervention once the sensor network is deployed.  There is only a finite source of energy as the nodes are not connected to any other energy source. Hence, communication should be minimized.  It is required that a sensor network system be adaptable to changing connectivity as well as changing environmental stimuli.