Monday, May 4, 2009
Jongdeog Lee
Chair: John A. Stankovic, Alfred C. Weaver
Advisor: Sang H. Son
OLSSON 236D, 13:30:00
A Master's Thesis Presentation
Design of an Architecture for Multiple Security Levels in Wireless Sensor Networks
ABSTRACT
With the increased application of wireless sensor networks (WSNs) in military, commercial, and home environments, securing the data in the network is a critical issue. Several security mechanisms, such as TinySec, have been introduced to address the need for security in WSNs. There are many applications, however, which require more than just protecting the data at a single level. For those applications, it is necessary to provide multilevel security (MLS) that can accommodate the different sensitivity levels of information as well as the different clearance levels of the users.
In this thesis, we apply the concept of MLS to the field of WSNs by employing the approach of multiple security levels (MSL). We employ cryptography techniques to realize the key aspects of MSL, the separation of different security domains and controlled information flow. Specifically, TinyKeyMan was selected as the key management scheme for this design due to its resilience to node compromise attack. In addition, we estimate the two dominant costs of the design: 1) communication overhead between different security domains and 2) cryptography costs (as measured by memory usage and energy consumption). Experiments show that placing the proper number of guards in the network helps to reduce network traffic overhead. Also, each security domain must select proper cryptography combinations (block ciphers, modes of operations, and message authentication codes) to satisfy both security and lifetime requirements. The MSL design we propose is simple and incurs low developmental costs, making it well-suited to resource constrained WSNs.