Title: Policy Analysis for Quality of Service Management
Author: Marinos Charalambides
e-mail: M.Charalambides@surrey.ac.uk
Partner: UniS
Supervisor: George Pavlou
Committee:
Year of start: 2003
Year of end: 2008
Funding institution: Centre for Communication Systems Research, University of Surrey
The rapid evolution of the Internet, the increasing complexities and heterogeneity of modern networking technology, and the increase in the number of resources to be managed, pose a significant challenge to network management models. Policy-based Network Management (PBNM) is a promising solution for these demands, providing the means by which the administration process can be simplified and largely automated in a flexible manner. The policy-based approach can be used to manage different aspects of a network commonly known as policy disciplines. The main interest in network policies is to manage and control the QoS experienced by networked applications and users, by configuring network elements using specific rules that define which traffic should be treated differently in the network, and how so.
Although extensive work has been done in developing policy specification languages, protocols and architectures to support policy-based management, little attention has been devoted to the area of policy analysis. Policy analysis is considered to be an essential component of modern PBNM solutions and comprises two functionalities: conflict detection and resolution.
In a real networking scenario, multiple policies will apply to network elements in order to support the requirements of different applications and users. Furthermore, the network’s shared resources are composed of several elements with varying capabilities and interfaces. Therefore, there is an apparent need for checking policy consistency prior to deployment, where a conflict detection process can identify any omissions, errors or conflicting requirements of the administrators specifying the policies. In the case of a conflict it is necessary to apply resolution techniques to either prevent a policy from being deployed or suggest ways in which the specification should change to guarantee policy integrity.
As such, the objectives of this thesis are to identify and classify policy conflicts related to the area of QoS management, and also define techniques and methodologies for their detection and resolution. More specifically, we investigate policy conflicts in the context of service and resource management in IP DiffServ Networks, and develop tools that provide support for both static and dynamic conflict detection as well as automated resolution. This work makes use of Event Calculus, a logic-based formalism, which apart from the representation of policies and managed components it provides the system with a certain degree of reasoning ability.