The manager/agency paradigm for distributed network management

The manager/agent model has been the de facto paradigm used for designing network management systems. However, as the network size grows and new network and computing technology emerges, consistency, flexibility, reliability, and scalability issues of distributed network management systems might not be fully addressed within the model. This paper proposes an extension to the manager/agent model, called the manager/agency paradigm, to address these issues. In the manager/agency paradigm, a manager performs management functions through an agency of cooperating management entities, (lower-level) managers and/of agents, which are collaboratively working together to achieve consistent management goals. Agencies may recursively constitute other agencies, based on the layering and partitioning principles, to scale with ever growing network size. They may be organized flexibly according to different management functionalities, goals and policies, and may present a single management view to their (upper-level) managers by hiding management complexity. Inside an agency, various fault tolerant schemes, such as active replication or primary-backup approach, may be used to implement reliable management functionality transparently to its manager. The paper begins by describing the anatomy and semantics of an agency and comparing the manager/agency model against the manager/agent model. It then demonstrates its applications to address the consistency and reliability issues of network management problems. Finally, applications of the manager/agency model to the broader, distributed enterprise management is discussed