The effect of (non-)competing brokers on the quality and price of differentiated internet services

Price war, as an important factor in undercutting competitors and attracting customers, has spurred considerable work that analyzes such conflict situation. However, in most of these studies, quality of service (QoS), as an important decision-making criterion, has been neglected. Furthermore, with the rise of service-oriented architectures, where players may offer different levels of QoS for different prices, more studies are needed to examine the interaction among players within the service hierarchy. In this paper, we present a new approach to modeling price competition in (virtualized) service-oriented architectures, where there are multiple service levels. In our model, brokers, as intermediaries between end-users and service providers, offer different QoS by adapting the service that they obtain from lower-level providers so as to match the demands of their clients to the services of providers. To maximize profit, players, i.e. providers and brokers, at each level compete in a Bertrand game while they offer different QoS. To maintain an oligopoly market, we then describe underlying dynamics which lead to a Bertrand game with price constraints at the providers’ level. We also study cooperation among a subset of brokers. Numerical simulations demonstrate the behavior of brokers and providers and the effect of price competition on their market shares.Accepted manuscrip

Pricing differentiated brokered internet services

Price war, as an important factor in undercutting competitors and attracting customers, has spurred considerable work that analyzes such conflict situation. However, in most of these studies, quality of service (QoS), as an important decision-making criterion, has been neglected. Furthermore, with the rise of service-oriented architectures, where players may offer different levels of QoS for different prices, more studies are needed to examine the interaction among players within the service hierarchy. In this paper, we present a new approach to modeling price competition in service-oriented architectures, where there are multiple service levels. In our model, brokers, as the intermediaries between end-users and service providers, offer different QoS by adapting the service that they obtain from lower-level providers so as to match the demands of their clients to the services of providers. To maximize profit, players at each level, compete in a Bertrand game, while they offer different QoS. To maintain an oligopoly market, we then describe underlying dynamics which lead to a Bertrand game with price constraints at the providers' level. Numerical examples demonstrate the behavior of brokers and providers and the effect of price competition on their market shares.http://www.cs.bu.edu/fac/matta/Papers/sdp2016.pdfAccepted manuscrip

Toward a Formal Semantics for Autonomic Components

Autonomic management can improve the QoS provided by parallel/ distributed applications. Within the CoreGRID Component Model, the autonomic management is tailored to the automatic - monitoring-driven - alteration of the component assembly and, therefore, is defined as the effect of (distributed) management code. This work yields a semantics based on hypergraph rewriting suitable to model the dynamic evolution and non-functional aspects of Service Oriented Architectures and component-based autonomic applications. In this regard, our main goal is to provide a formal description of adaptation operations that are typically only informally specified. We contend that our approach makes easier to raise the level of abstraction of management code in autonomic and adaptive applications.Comment: 11 pages + cover pag

Service Quality and Profit Control in Utility Computing Service Life Cycles

Utility Computing is one of the most discussed business models in the context of Cloud Computing. Service providers are more and more pushed into the role of utilities by their customer's expectations. Subsequently, the demand for predictable service availability and pay-per-use pricing models increases. Furthermore, for providers, a new opportunity to optimise resource usage offers arises, resulting from new virtualisation techniques. In this context, the control of service quality and profit depends on a deep understanding of the representation of the relationship between business and technique. This research analyses the relationship between the business model of Utility Computing and Service-oriented Computing architectures hosted in Cloud environments. The relations are clarified in detail for the entire service life cycle and throughout all architectural layers. Based on the elaborated relations, an approach to a delivery framework is evolved, in order to enable the optimisation of the relation attributes, while the service implementation passes through business planning, development, and operations. Related work from academic literature does not cover the collected requirements on service offers in this context. This finding is revealed by a critical review of approaches in the fields of Cloud Computing, Grid Computing, and Application Clusters. The related work is analysed regarding appropriate provision architectures and quality assurance approaches. The main concepts of the delivery framework are evaluated based on a simulation model. To demonstrate the ability of the framework to model complex pay-per-use service cascades in Cloud environments, several experiments have been conducted. First outcomes proof that the contributions of this research undoubtedly enable the optimisation of service quality and profit in Cloud-based Service-oriented Computing architectures

An Approach to Transform Public Administration into SOA-based Organizations

Nowadays, Service-Oriented Architectures (SOA) is widely spread in private organizations. However, when transferring this knowledge to Public Administration, it is realized that it has not been transformed in terms of its legal nature into organizations capable to operate under the SOA paradigm. This fact prevents public administration bodies from offering the efficient services they have been provided by different boards of governments. A high-level framework to perform this transformation is proposed. Taking it as starting point, an instance of a SOA Target Meta-Model can be obtained by means of an iterative and incremental process based on the analysis of imperatives and focused on the particular business context of each local public administration. This paper briefly presents a practical experience consisting in applying this process to a Spanish regional public administration.Junta de Andalucía TIC-578

Norms, organisations and semantic web services: The ALIVE approach

ALIVE is an EU FP7 STREP whose goal is the convergence of organisational and normative modelling with and service-oriented architectures (SOAs) using model-driven software engineering. The project provides a framework for designing and implementing systems, taking into account organisational, coordination and service perspectives. A key project aspect is the integration of normative systems with live SOAs, through the distributed monitoring of normative state. Here we give a brief overview of the project, explore of the domain from a service context, outline the architecture under construction and sketch the use-cases that illustrate and inform the project.Peer ReviewedPostprint (published version

A goal-oriented approach for the generation and evaluation of alternative architectures

There is a recognized gap between requirements and architectures. There is also evidence that architecture evaluation, when done at the early phases of the development lifecycle, is an effective way to ensure the quality attributes of the final system. As quality attributes may be satisfied at a different extent by different alternative architectural solutions, an exploration and evaluation of alternatives is often needed. In order to address this issue at the requirements level, we propose to model architectures using the i* framework, a goal-oriented modelling language that allows to represent the functional and non-functional requirements of an architecture using actors and dependencies instead of components and connectors. Once the architectures are modelled, we propose guidelines for the generation of alternative architectures based upon existing architectural patterns, and for the definition of structural metrics for the evaluation of the resulting alternative models. The applicability of the approach is shown with the Home Service Robot case study.Peer ReviewedPostprint (author's final draft

Multi Domain-Specific Modeling of the Security Concerns of Service-Oriented Architectures

Service-Oriented Architectures (SOA), and Web Services (WS), the technology generally used to implement them, achieve the integration of heterogeneous technologies, providing interoperability, and yielding the reutilization of pre-existent systems. Model-driven development methodologies provide inherent benefits such as increased productivity, greater reuse, and better maintainability, to name a few. Efforts on achieving model-driven development of SOAs already exist, but there is currently no standard solution that addresses non-functional aspects of these services as well. This paper presents an approach to integrate these non-functional aspects in the development of web services, with an emphasis on security