Mobile agent-based energy-efficient and secure global information systems

by Jiao, Yu.

In this thesis, we proposed and prototyped a novel, energy-efficient, and secure global information infrastructure called MAMDAS, which stands for Mobile Agent-based Mobile Data Access System framework. MAMDAS combines the merits of the summary-schemas multidatabase organization model and mobile agents in building distributed large-scale information access systems. It addresses four major challenges in global information system design: (i) data source heterogeneity and autonomy, (ii) user and data source mobility, (iii) energy-efficient wireless information retrieval, and (iv) information security. First, the summary-schemas model was chosen to respond to the problem of data source heterogeneity and autonomy. Second, the use of mobile agents alleviates the dependency on network connectivity and thus, provides support for both user and data source mobility. It also improves system performance by reducing the communication overhead. Moreover, the use of mobile agents can significantly reduce the maintenance cost of large and complex systems because of the improved software modularity and reusability. Third, in order to address the energy-efficiency issues in mobile computing, we developed an application-driven adaptive dynamic power management protocol that can minimize the energy consumption of the wireless network interface card while maintaining high throughput. This protocol serves not only as the energy conservation strategy for MAMDAS, but also as a general solution to wireless information retrieval applications. Finally, we devised security architecture for MAMDAS, which follows the rule of mechanism-policy separation. It constitutes two main components: the security extension of IBM Java Aglets Workbench and application level security policy. Our design allows all applications built on top of the IBM Aglets Workbench share the security services provided by the agent platform. In addition, each application has the flexibility to define security policies that best suit its needs. It is envisioned that this energy-efficient and secure data access framework be widely used in applications such as global information search engines, E-commerce, E- government, etc.