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The routing tables of Distributed Hash Tables (DHTs) can vary from size O(1) to O(n). Currently, what is lacking is an analytic framework to suggest the optimal routing table size for a given workload. This paper (1) compares DHTs with O(1) to O(n) routing tables and identifies some good design points; and (2) proposes protocols to realize the potential of those good design points.We use total traffic as the uniform metric to compare heterogeneous DHTs and emphasize the balance between maintenance cost and lookup cost. Assuming a node on average processes 1,000 or more lookups during its entire lifetime, our analysis shows that large routing tables actually lead to both low traffic and low lookup hops. These good design points translate into one-hop routing for systems of medium size and two-hop routing for large systems.Existing one-hop or two-hop protocols are based on a hierarchy. We instead demonstrate that it is possible to achieve completely decentralized one-hop or two-hop routing, i.e., without giving up being peer-to-peer. We propose 1h-Calot for one-hop routing and 2h-Calot for two-hop routing. Assuming a moderate lookup rate, compared with DHTs that use O(log n) routing tables, 1h-Calot and 2h-Calot save traffic by up to 70% while resolving lookups in one or two hops as opposed to O(log n) hops.

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People, processes, technology and information are the essential building blocks for creating a successful IT infrastructure in today's fast-paced, service-focused marketplace. ITIL which is recognized as the de facto standard for service management is a process based approach. ITIL focuses on a set of integrated processes which run the gamut from highly interactive and dynamic processes such as problem determination to highly repeatable processes such as patch deployment which are best handled in a fully automated, non-interactive fashion. The ability to support and integrate the full spectrum of interactivity for these processes with the appropriate level of automation is crucial for the service provider. Also key is the ability to identify opportunities to increase the level of automation as maturity and technology permit.In this paper, we propose a conceptual methodology for IT service management process automation that leverages the ontological relationships between process artifacts and resource artifacts to develop data aware processes for an effective automated approach to integrate both highly automated and human centric process models. The objective is to develop a systematic approach that addresses the needs of an IT organization in order that highly automated operational processes work in conjunction with collaborative human decision centric processes in order to effectively deliver IT services. In addition, we propose a complexity model to assist in identifying automation opportunities to satisfy the need for continuous efficiency and cost improvement.