Service architecture design for E-Businesses: A pattern-based approach

E-business involves the implementation of business processes over the Web. At a technical level, this imposes an application integration problem. In a wider sense, the integration of software and business levels across organisations becomes a significant challenge. Service architectures are an increasingly adopted architectural approach for solving Enterprise Applications Integration (EAI). The adoption of this new architectural paradigm requires adaptation or creation of novel methodologies and techniques to solve the integration problem. In this paper we present the pattern-based techniques supporting a methodological framework to design service architectures for EAI. The techniques are used for services identification, for transformation from business models to service architectures and for architecture modifications

Performance Testing of Distributed Component Architectures

Performance characteristics, such as response time, throughput andscalability, are key quality attributes of distributed applications. Current practice,however, rarely applies systematic techniques to evaluate performance characteristics.We argue that evaluation of performance is particularly crucial in early developmentstages, when important architectural choices are made. At first glance, thiscontradicts the use of testing techniques, which are usually applied towards the endof a project. In this chapter, we assume that many distributed systems are builtwith middleware technologies, such as the Java 2 Enterprise Edition (J2EE) or theCommon Object Request Broker Architecture (CORBA). These provide servicesand facilities whose implementations are available when architectures are defined.We also note that it is the middleware functionality, such as transaction and persistenceservices, remote communication primitives and threading policy primitives,that dominates distributed system performance. Drawing on these observations, thischapter presents a novel approach to performance testing of distributed applications.We propose to derive application-specific test cases from architecture designs so thatthe performance of a distributed application can be tested based on the middlewaresoftware at early stages of a development process. We report empirical results thatsupport the viability of the approach

A framework for the definition of metrics for actor-dependency models

Actor-dependency models are a formalism aimed at providing intentional descriptions of processes as a network of dependency relationships among actors. This kind of models is currently widely used in the early phase of requirements engineering as well as in other contexts such as organizational analysis and business process reengineering. In this paper, we are interested in the definition of a framework for the formulation of metrics over these models. These metrics are used to analyse the models with respect to some properties that are interesting for the system being modelled, such as security, efficiency or accuracy. The metrics are defined in terms of the actors and dependencies of the model. We distinguish three different kinds of metrics that are formally defined, and then we apply the framework at two different layers of a meeting scheduler system.Postprint (published version