Dynamic Access Control Mechanism for Shared Wireless Sensor Networks

Abstract

Researchers and organizations from various disciplines are interested in using Wireless Sensor Network (WSN) for their research and applications. However, deploying a sensor network of their own is a difficult task for these communities due to high cost of deployment and maintenance. Therefore, the concept of Shared Wireless Sensor Network (SWSN) is getting popular among these communities. But providing shared access for WSN has given rise to different set of problems. Controlling access among users in SWSN is an important issue which we consider in this research. Although there are many access controlling schemes for users in WSN, those schemes are difficult to use on SWSNs because of their limitations. In this research, we propose an access control mechanism that can overcome challenges and problems related to user access controlling in a SWSN such as handling dynamic nature of user privileges, attacks from forged base stations and malicious users. This access controlling mechanism is implemented as a module to the TikiriDB data abstraction layer which runs on Contiki development environment and it uses both symmetric cryptography and public key cryptography with an effective key management scheme to ensure the security of the system. According to the design, there are three main ways of energy consumption in the network. They are energy for communication, sensing and authentication process inside the node. By adding this mechanism to a SWSN, it increases energy for communication and processing at the node than a network without this mechanism, but it decreases energy for sensing because nodes execute only the queries of authorized users. Also, since this access controlling scheme is deployed at the node level, each node have to process individually. So the failure of the nodes does not impact on total access controlling process. Therefore, it gives node failure recovery as an additional advantage.