Guerney D. H. Hunt

Network dispatcher: a connection router for scalable Internet services

Abstract Network Dispatcher (ND) is a TCP connection router that supports load sharing across several TCP servers. Prototypes of Network Dispatcher were used to support several large scale high-load Web sites. Network Dispatcher provides a fast IP packet-forwarding kernel-extension to the TCP IP stack. Load sharing is supported by a user-level manager process that monitors the load on the servers and controls the connection allocation algorithm in the kernel extension. This paper describes the design of Network Dispatcher, outlines Network Dispatchers performance in the context of http traffic, and presents several of its features including high-availability, support for WANs, and client affinity.

Using a utility computing framework to develop utility systems

In this paper we describe a utility computing framework, consisting of a component model, a methodology, and a set of tools and common services for building utility computing systems. This framework facilitates the creation of new utility computing systems by providing a set of common functions, as well as a set of standard interfaces for those components that are specialized. It also provides a methodology and tools to assemble and re-use resource provisioning and management functions used to support new services with possibly different requirements. We demonstrate the benefits of the framework by describing two sample systems: a life-science utility computing service designed and implemented using the framework, and an on-line gaming utility computing service designed in compliance with the framework.

Guest Editors' Introduction: Pervasive Computing in Sports Technologies

Sensors and other ubiquitous computing technologies have slowly penetrated the arena of sports. This special issue gives some excellent examples of pervasive technology in sports and points to future directions.

Enabling location-based applications

We identify a number of factors that may hinder the commercial success of location-based applications: the concern of privacy, the need to consider context beyond location, the presence of voluminous resources, and the constrained interfaces available on mobile devices. We describe an end-to-end system architecture with integrated support to address these issues. In particular, the architecture includes a Secure Context Service that provides broad context information to applications and allows people to flexibly control the release of their private information, an Intelligent Service Discovery Service that allows for personalized selection of physical and virtual services, and a multi-modal interaction mechanism that enables users to exploit multiple synchronized access channels to interact with an application and to switch among channels at any time. Our goals are to improve user experience, to reduce user distraction and to facilitate awareness of the physical world.