Showing papers on "Differentiated service published in 1981"

Methods, Tools, and Observations on Flow Control in Packet-Switched Data Networks

Abstract: Flow control covers several concepts. In an end-to-end connection, it intends to adapt sender's output to receiver's capabilities. In a shared resources communication network, it attempts to prevent congestion by restricting traffic flows. Flow control mechanisms are built with a small number of basic throttling tools. However, they are always tied into a resource management problem, which depends on a large variety of environmental parameters. Techniques used in end-to-end connections are summarized. Congestion control in store-and-forward packetswitching networks is covered extensively, and techniques used or proposed are discussed. Memoryless networks, such as broadcast local networks are shown to be simpler systems in the area of flow control. In conclusion, arguments are made for a service oriented approach, which would optimize resource usage through differentiated service characteristics.

Measuring the effectiveness of computing services

Abstract: This paper reports aspects of a study of the characteristics of a university computer service, the “amateur programmer” users of that service, and of the nature of the interaction that exists between them.The aim was to develop both an understanding of these and a tool that could be used to evaluate the effectiveness of the service provided by any computing service organisation. The criteria used for evaluation were based on two premises: one, that the effectiveness of a computing service is reflected in the degree of satisfaction of its users, and two, that this in turn can be gauged by asking users through questionnaires and interviews how they feel about things.Mathematical techniques were devised to examine the patterns of user responses to a variety of questions about themselves, the facilities they use and their feelings about them. From these patterns factors underlying the overall effectiveness of the service were exposed. These could have important managerial implications, as, for example, in the choice between investment in hardware and software and investment in human support services.

Operational considerations for mobile service units

Abstract: The paper develops several relationships that can help determine operational characteristics of a mobile service unit. Specifically, it presents a heuristic for the determination of a service area using service level and waiting time criteria and deal's with the decentralization of service units. These relationships may be applied in various contexts: assignment of maintenance crews, dispatching material handling equipment, determining airlines service areas, among others.