P2P, ad hoc and sensor networks – All the different or all the same?

Currently, data management technologies are in the process of finding their way into evolving networks, i.e. P2P, ad hoc and wireless sensor networks. We examine the properties, differences and commonalities of the different types of evolving networks, in order to enable the development of adequate technologies suiting their characteristics. We start with presenting definitions for the different network types, before arranging them in a network hierarchy, to gain a clear view of the area. Then, we analyze and compare the example applications for each of the types using different design dimensions. Based on this work, we finally present a comparison of P2P, ad hoc and wireless sensor networks

A Fast and Robust Failure Recovery Scheme for Shared-Nothing Gigabit-Networked Databases

Major technological advances have enabled the development of very high speed networks with data rates of the order of gigabits per second. In the future, wide area gigabit networks will interconnect database servers around the globe creating extremely powerful distributed information systems. In a high speed network, the size of the message is less of a concern than the number of sequential phases of message passing. In a previous paper, we have developed a lock-based concurrency control protocol for gigabit-networked databases (GNDB). In this paper, we expand on a log-based recovery protocol that provides efficient recovery in a GNDB with the above mentioned concurrency control scheme. 1 Introduction Several exciting advances are being made in the general area of high speed distributed computing. For instance, the rate at which information can be transmitted [12] and the rate at which information can be processed is increasing. Also, user desktops are being enhanced to the point tha..

ACTA: a comprehensive transaction framework for extended transactions

Summary form only given. Although powerful, the transaction model adopted in traditional database systems is found lacking in functionality and performance when used for new applications, such as CAD/CAM, and design environments. Various extensions to traditional transaction model have been proposed to address these drawbacks. In order to analyze these ad hoc extensions and in search for a good implementation support for the new applications, the authors have developed a comprehensive transaction framework, called ACTA. ACTA characterizes the semantics of interactions in terms of different types of dependences between transactions and in terms of transactions' effects on objects

A logically distributed approach for structuring office systems

An object-oriented office model is presented. It uses the object taxonomy of Booch featuring object classes based on calling patterns. Our model is motivated by that of Woo and Lochovsky, but has a number of differences, especially in the definition of the object classes and in the treatment of nested objects. An office application, setting a meeting among office workers, is defined in terms the office model

Requirements-Based Design Evaluation

This paper presents a methodology for automating the evaluation of partial designs using black-box testing techniques. This methodology generates black-box evaluation tests using a novel semantic graph data model to maintain the relationships between the related design and requirements data. We demonstrate the utility of this technique by using the relationship information to automatically generate and run functionality tests of partial designs against the related requirements. I. Introduction Current Computer-Aided Design (CAD) tools are geared to help the designer develop good designs from specifications. Likewise, current computer-aided requirements tools are geared to help the analyst formulate good requirements, and create specifications. However, designs often have their requirements change while the design is being developed, and there is little support for continually reflecting these changes in the specifications. Consequently, the quality of the design (i.e., how well the de..

Linking Requirements and Design Data for Automated Functional Evaluation

This paper presents a methodology for automating the evaluation of complex hierarchical designs using black-box testing techniques. Based on an exploration model for design, this methodology generates evaluation tests using a novel semantic graph data model which captures the relationships between the related design and requirements data. Using these relationships, equivalent tests are generated and systematically applied to simulations of the pieces of a modular design and its requirements. These simulations yield two sets of comparable results, enabling evaluation of partial designs of a complex system early in their design process