Implications of Selfish Neighbor Selection in Overlay Networks

In a typical overlay network for routing or content sharing, each node must select a fixed number of immediate overlay neighbors for routing traffic or content queries. A selfish node entering such a network would select neighbors so as to minimize the weighted sum of expected access costs to all its destinations. Previous work on selfish neighbor selection has built intuition with simple models where edges are undirected, access costs are modeled by hop-counts, and nodes have potentially unbounded degrees. However, in practice, important constraints not captured by these models lead to richer games with substantively and fundamentally different outcomes. Our work models neighbor selection as a game involving directed links, constraints on the number of allowed neighbors, and costs reflecting both network latency and node preference. We express a node's "best response" wiring strategy as a k-median problem on asymmetric distance, and use this formulation to obtain pure Nash equilibria. We experimentally examine the properties of such stable wirings on synthetic topologies, as well as on real topologies and maps constructed from PlanetLab and AS-level Internet measurements. Our results indicate that selfish nodes can reap substantial performance benefits when connecting to overlay networks composed of non-selfish nodes. On the other hand, in overlays that are dominated by selfish nodes, the resulting stable wirings are optimized to such great extent that even non-selfish newcomers can extract near-optimal performance through naive wiring strategies.Marie Curie Outgoing International Fellowship of the EU (MOIF-CT-2005-007230); National Science Foundation (CNS Cybertrust 0524477, CNS NeTS 0520166, CNS ITR 0205294, EIA RI 020206

School Web Sites within the Educational Marketplace: A Case Study Investigating the Parents as Engaged Consumer-Users

Schools -- like their corporate counterparts -- recognize the many advantages that the Internet affords. Today\u27s schools vie for students, and thus use the web to market their services and showcase their management team (administrators, teachers, staff) and academic accomplishments. In a sense, then, web sites are the public face of education; those that are well-designed and multi-featured can enhance a district\u27s public image and create the perception of excellence and competence. This case study explores how one suburban, K-8 school district approaches web site development, specifically, the process by which decisions about design, development, and maintenance are made (and by whom); the ways in which they engage those who explore them--with a particular focus on parents; and, how well the sites adhere to generally recognized design attributes. Data were gathered through interviews with school administrators, document review, web site analysis, parent surveys, and parent focus groups. Results offer information to policymakers, administrators, and site designers regarding principles of web design unique to parents as educational consumers. Principles emerging from the case study can lead to additional research not only in the field of education, but, also, in the fields of web design and marketing

Semantic discovery and reuse of business process patterns

Patterns currently play an important role in modern information systems (IS) development and their use has mainly been restricted to the design and implementation phases of the development lifecycle. Given the increasing significance of business modelling in IS development, patterns have the potential of providing a viable solution for promoting reusability of recurrent generalized models in the very early stages of development. As a statement of research-in-progress this paper focuses on business process patterns and proposes an initial methodological framework for the discovery and reuse of business process patterns within the IS development lifecycle. The framework borrows ideas from the domain engineering literature and proposes the use of semantics to drive both the discovery of patterns as well as their reuse

The Strategic Distribution Management Initiative and its effects on inventory levels and readiness

Until just a few years ago, no organization was tasked with measuring overall effectiveness, design, or optimization of DOD's global supply chain management system. As a result, the Strategic Distribution Management Initiative (SDMI) was created as a joint venture between Defense Logistics Agency (DLA) and the United States Transportation Command (USTRANSCOM) charged with enterprise level redesign, streamlining, and optimization of the DOD global supply chain. This thesis examines the affects of the SDMI implementation on the Army's two maneuver divisions stationed in the Europe. Specifically, it analyzes affects of SDMI implementation on the eight supply support activities located within the two maneuver divisions in USAREUR. This thesis studies SDMI impacts on inventory levels; inventory turbulence in the SSAs during SDMI implementation; SDMI improvements with respect to readiness; and existing barriers to improving velocity. The research indicates that: (1) expected inventory reductions were not realized following SDMI implementation, (2) inventory turbulence consumes limited resources and is a lucrative target for further improvement, (3) there is no evidence that SDMI increased fleet readiness, and (4) backorder rates and time, along with sub-optimization of pieces of the DOD supply chain, are significant barriers to velocity that still must be broken through.http://archive.org/details/thestrategicdist109455797Approved for public release; distribution is unlimited