Policies Hierarchies for Distributed Systems Management

Distributed system management, involves monitoring the activity of a system, making management decisions and performing control actions to modify the behaviour of the system. Most of the research on management has concentrated on management mechanisms related to Network Management or Operating Systems. However, in order to automate the management of very large distributed systems, it is necessary to be able to represent and manipulate management policy within the system. These objectives are typically set out in the form of general policies which require detailed interpretation by the system managers. This paper explores the refinement of general high-level policies into a number of more specific policies to form a policy hierarchy in which each policy in the hierarchy represents, to its maker, his plans to meet his objectives and, to its subject, the objectives which he must plan to meet. Management action policies are introduced, and the distinction between imperatival and authority policies is made. The relationship of hierarchies of imperatival policies to responsibility, and to authority policies, is discussed. An outline approach to the provision of automated support for the analysis of policy hierarchies is provided, by means of a more formal definition of policy hierarchy refinement relationships in Prolog.