Enhancing Trustworthiness and Reliability of Wireless Sensor Networks while Reducing Energy Consumption

S. M. Iftekharul Alam, Purdue University

Abstract

Sensor nodes are resource-constrained and prone to hardware or software faults. The faulty sensors may report corrupted or untrustworthy data and experience run-time problems (such as crash, unresponsive radio) leading to network failures. These problems make it challenging to meet the reliability requirements of the application in terms of data quality and network performance. In this dissertation, we propose a number of methods and tools to facilitate reliable operation of a wireless sensor network while maintaining low energy overhead. In order to assess the trustworthiness of data, we consider provenance based trust frameworks, which evaluate the trustworthiness of data items based on the intuition that two data items with similar data values but with different provenance (i.e., forwarding path) can be considered more trustworthy. Operating many sensors with dissimilar paths, however, consumes significant energy. By leveraging this trade-off between energy cost and trustworthiness, we design a scheme called ERUPT, which determines a set of sensor nodes and their corresponding forwarding paths that achieve a certain trustworthiness threshold with reduced energy consumption. We also find that transmitting provenance along with data packet requires a large and variable number of bits in each packet, resulting in high energy dissipation. To overcome this problem, we propose energy-efficient provenance encoding and construction schemes, known as PPF, which probabilistically incorporates a connected subgraph of the forwarding path into the fixed-size bit space of a packet. Since faulty nodes often cause network failures apart from producing inconsistent data, we devise Feluda, an energy-efficient diagnostic framework, which exploits provenance and packet headers to find reasons behind certain network problems. Once specific reasons (e.g. changing environmental conditions, configuration errors) are identified, over-the-air software modification may become necessary to fix the problems. In this regard, we design a dissemination protocol, SYREN, which exploits the synergy between link correlation and network coding to enable reliable and faster software update with reduced transmission overhead. Finally, we demonstrate the effectiveness of our proposed methods and tools through real-world testbed experiments and simulations.

Degree

Ph.D.

Advisors

Hu, Purdue University.

Subject Area

Computer Engineering

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