Proof-of-Concept Application - Annual Report Year 2

This document first gives an introduction to Application Layer Networks and subsequently presents the catallactic resource allocation model and its integration into the middleware architecture of the developed prototype. Furthermore use cases for employed service models in such scenarios are presented as general application scenarios as well as two very detailed cases: Query services and Data Mining services. This work concludes by describing the middleware implementation and evaluation as well as future work in this area. --Grid Computing

Web services for rural areas-Security challenges in development and use

Web services (WS) are the modern response of traders and online service providers to satisfying the increasing needs and demands of the digital communities. WS formation and operation is based on a software system designed to support interoperable machine-to-machine interaction over a network. Security is of paramount importance to WS and the ability to measure and evaluate the level of security available is key to establishing and continuing to develop the level of trust based on reputation developed by the provider of the WS. The greatest challenge in offering secure WS is to groups of people where the level of expertise of the user is low and the need for transparency of the service provision quite high, such as the case with services offered primarily to people in rural areas. Providers of such services face many challenges in balancing the requirements for performance, interoperability, and security against the cost of implementing secure systems and running profitable operations through low income generating WS. A review of services offered, of the users and the challenges in building online trust among providers and users are discussed for the case of rural areas in the United Kingdom. © 2009 Elsevier B.V. All rights reserved

An investigation of interoperability issues between authorisation systems within web services

The existing authorisation systems within the context of Web Services mainly apply two access control approaches – Role-Based Access Control (RBAC) and Attribute-Based Access Control (ABAC). The RBAC approach links an authenticated Web Service Requester to its specific access control permission through roles, but RBAC is not flexible enough to cater for some cases where extra attribute information is needed in addition to the identity. By contrast, the ABAC approach has more flexibility, as it allows a Web Service Requester to submit necessary credentials containing extra attribute information that can fulfil the policies declared by a Web Service Provider, which aims to protect the sensitive resources/services.RBAC and ABAC can only help to establish a unilateral trust relationship between two Web Services to enable a Web Service Provider to make an access control decision. Unfortunately, the nature of Web Services presents a high probability that two Web Services may not know each other. Therefore, successful authorisation may fail, if the Web Service Requester does not trust the Web Service Provider.Trust Negotiation (TN) is also an access control approach, which can provide a bilateral trust relationship between two unknown entities, so it sometimes can enable authorisation success in situations where success is not possible through RBAC or ABAC approaches. However, interoperability issues will arise between authorisation systems within Web Services, where a bilateral trust-based authorisation solution is applied. In addition, a lack of a unified approach that can address the interoperability issues remains as a research problem. This research aims to explore possible factors causing the lack of interoperability first, and then to explore an approach that can address the interoperability issues. The main contributions of this research are an improved interoperability model illustrating interoperability issues at different layers of abstraction, and a novel interoperability-solution design along with an improved TN protocol as an example of utilising this design to provide interoperability between authorisation systems within Web Services

A business-oriented framework for enhancing web services security for e-business

Security within the Web services technology field is a complex and very topical issue. When considering using this technology suite to support interacting e-businesses, literature has shown that the challenge of achieving security becomes even more elusive. This is particularly true with regard to attaining a level of security beyond just applying technologies, that is trusted, endorsed and practiced by all parties involved. Attempting to address these problems, this research proposes BOF4WSS, a Business-Oriented Framework for enhancing Web Services Security in e-business. The novelty and importance of BOF4WSS is its emphasis on a tool-supported development methodology, in which collaborating e-businesses could achieve an enhanced and more comprehensive security and trust solution for their services interactions. This investigation began with an in-depth assessment of the literature in Web services, e-business, and their security. The outstanding issues identified paved the way for the creation of BOF4WSS. With appreciation of research limitations and the added value of framework tool-support, emphasis was then shifted to the provision of a novel solution model and tool to aid companies in the use and application of BOF4WSS. This support was targeted at significantly easing the difficulties incurred by businesses in transitioning between two crucial framework phases. To evaluate BOF4WSS and its supporting model and tool, a two-step approach was adopted. First, the solution model and tool were tested for compatibility with existing security approaches which they would need to work with in real-world scenarios. Second, the framework and tool were evaluated using interviews with industry-based security professionals who are experts in this field. The results of both these evaluations indicated a noteworthy degree of evidence to affirm the suitability and strength of the framework, model and tool. Additionally, these results also act to cement this thesis' proposals as innovative and significant contributions to the research field

Automated Negotiation Among Web Services

Software as a service is well accepted software deployment and distribution model that is grown exponentially in the last few years. One of the biggest benefits of SaaS is the automated composition of these services in a composite system. It allows users to automatically find and bind these services, as to maximize the productivity of their composed systems, meeting both functional and non-functional requirements. In this paper we present a framework for modeling the dependency relationship of different Quality of Service parameters of a component service. Our proposed approach considers the different invocation patterns of component services in the system and models the dependency relationship for optimum values of these QoS parameters. We present a service composition framework that models the dependency relations ship among component services and uses the global QoS for service selection