Abstract
Wireless ad hoc networks pose major research challenges because of their increasing ubiquity and user-initiated formation. The motivation of this thesis emanates from the need for unrestricted wireless communication in a scalable and predictable manner. This need is accentuated by the increasing users' demand for spontaneous communication and the deficiencies of existing management frameworks. The objective is to propose a management framework able to leverage the potential of wireless ad hoc networks as an alternative communication method allowing them to coexist with other networks and to emerge as their flexible extension. In the context of this thesis, wireless ad hoc networks consist of a majority of end-user devices, capable of multihop communication, and optionally supported from limited infrastructure. The policy-based management (PBM) paradigm is employed to facilitate their self-management, combining design and theory with testbed implementation and simulation studies. The thesis contribution can be identified in three areas: (1) Design of a context-aware policy hierarchy and a hybrid role-based organisation model: The integration of policies with contextual feedback enables the creation of a closed control loop at different organisational levels, forming the basis for self-management. (2) Deployment of distributed PBM functionality. The management of wireless ad hoc networks is possible with the decentralisation of traditional PBM concepts, based on the design and implementation of a Distributed Policy Repository (DPR). The DPR assists in the coordination of dispersed policy decision points (PDPs) by facilitating the synchronisation of policies and offering a uniform view of management objectives to the PDPs. (3) Validation of PBM functionality for self-management. A case study addresses the deployment of a wireless ad hoc network on a testbed, attempting to overcome the lack of central coordination and the occurrence of interference, by using policies to control its dynamic channel assignment. Finally, the framework is extended for service management, implementing adaptable service provisioning and offering service customisation to end-users. The elements of this thesis contribution are combined under a unified policy-based framework for the self-management of wireless ad hoc networks.