Hisain Elshaafi

Trustworthiness Inference of Multi-tenant Component Services in Service Compositions

This paper presents a novel approach to the inference of trustworthiness of individual components shared between multiple composite services in distributed services environments. In such environments, multiple component services are orchestrated from distributed providers to create new value-added services. A component service can be shared by several distributed compositions. A composite service is offered to its consumers who rate its reliability and satisfaction after each transaction. However, since composite services are provided as an integrated service it is not possible to attribute failures or causes of dissatisfaction to individual components in isolation. A collaborative detection mechanism can provide a solution to the evaluation of component trustworthiness based on consumer reporting of composite service execution results.

Aggregation of trustworthiness properties of BPMN-based composite services

Some of the important characteristics of services environments are being dynamic, distributed, loosely coupled and open. These characteristics result in the existence of different levels of functional and non-functional properties of the services operating in such environments. Consequently, it creates challenges for interacting service consumers that require to only deal with services that are trustworthy. In service compositions, the component services may be mandatory or optional and vary in their contribution to the trustworthiness of the composite service. Composition techniques must be able to select trustworthy components and to dynamically adapt to subsequent changes in the services and the environment. The availability of multiple services providing the same or similar functionality but with different trustworthiness levels helps composite service providers to establish and maintain trustworthy compositions. The paper describes an approach to the aggregation of trustworthiness properties of composite services that are assembled from more fine-grained component services. The approach is developed for composite services based on BPMN business processes but can be extended to other languages.

Optimisation-based collaborative determination of component trustworthiness in service compositions

In service-oriented environments, service providers orchestrate distributed services from other providers to create new composite enterprise services. A component service can be invoked jointly by several distributed composite service providers. However, because a composite service is provided to the consumers as an integrated service, when failures or dissatisfaction of the consumers occurs, it is not possible to directly identify the untrustworthy component. In this paper, we describe a collaborative trustworthiness determination approach using optimisation that can provide a solution to selecting trustworthy component service constructs based on monitoring and consumer quality of experience reporting of existing composite services from peer providers. Copyright

Trust Management in Monitoring Financial Critical Information Infrastructures

The success of Internet-based attacks and frauds targeting financial institutions highlights their inadequacy when facing such threats in isolation. Financial players need to coordinate their efforts by sharing and correlating suspicious activities occurring at multiple, geographically distributed sites. CoMiFin, an European project, is developing a collaborative security framework, on top of the Internet, centered on the Semantic Room abstraction. This abstraction allows financial institutions to share and process high volumes of events concerning massive threats (e.g., Distributed Denial of Service) in a private and secure way. Due to the sensitive nature of the information flowing in Semantic Rooms, and the privacy and security requirements then required, mechanisms ensuring mutual trust among Semantic Room members (potentially competitive financial players) must be provided. This paper focuses on the design and preliminary implementation of a trust management architecture that can be configured with trust and reputation policies and deployed in Semantic Rooms.

Trustworthiness monitoring of dynamic service compositions

In Web service compositions the number of component services that need to be aggregated may be large and dynamically changing. Web service (WS) compositions require the capability to dynamically adapt to changes that may occur at runtime, including changes in the environment and in the component services themselves. Service composers must be able to respond swiftly to changed trustworthiness (TW) requirements and capabilities of service compositions, where those changes may not be easily predictable. With the availability of alternative services providing the same functionality as those already integrated in a service composition, service composers can take advantage of this by dynamically replacing degrading or unsatisfactory components. This paper provides techniques and an approach to dynamically detect and replace component services based on their trustworthiness.

Trust and Privacy

In this chapter we demonstrate how to increase the value of shared information by providing context on its quality via trust metrics. In order to evaluate the achieved level of trust, a trust evaluation system is described. This system assesses the quality of information based on past behaviour, direct experience, recommendation, referral, and roles. This management process filters and prioritises information provided by Semantic Room (SR) members while dynamically adjusting the trust level of members.

Combination of Standards to Support Flexibility Management in the Smart Grid, Challenges and Opportunities

This paper presents the results of an assessment of a wide range of standards in the smart grid and telecommunications domains that may be jointly used to implement three use cases focusing on the use of the multi-agent systems paradigm in enhancing the smart grid particularly in the area of flexibility management. In addition to supporting a decentralised grid, multi-agent systems can improve other aspects such as reliability, performance and security. The paper identifies relevant standards based on a set of key smart grid use cases from the EU Mas2tering project. The evaluation aims to provide recommendations on combining those standards. This will enable new collaboration opportunities between grid operators, telecom and energy companies, both from technology and business perspectives. The set of telecommunication and energy standards is identified based on existing EU smart grid implementations, models (such as the Smart Grid Architecture Model) and reports published by the European and International standardisation bodies and coordination groups.

Attack surface-based security metric framework for service selection and composition

Security in service-oriented computing is important in ensuring trustworthiness of services both atomic and composite. However, in order to select and compose services that are most secure and trustworthy, there is a need for metrics to evaluate and rank those services in terms of their security attributes. The area of security metrics and quantification has recently gained significant attention and made some progress. This paper proposes a framework for quantifying security of component services and their compositions based on the concept of attack surfaces to help compose and provide the most trustworthy composite services. The framework allows composite service providers to address multifaceted security issues in composite services and measure improvements resulting from changes to component configurations, application of business process security extensions or other actions.

Collaborative Framework for Monitoring Reliability of Distributed Components of Composed Services

In this paper we describe a collaborative agent-based framework that allows service providers to monitor and evaluate component reliability using reports of the results of composed service executions. In the framework, service providers share reliability data with each other to mutually maintain the reliability of their services and protect them from unreliable components. Consumers rate success or failure of the composed service after each transaction. In service environments, providers can utilise component services offered by other providers to create new enterprise services. Therefore, a distributed component service can be executed simultaneously by several composed services. Since a composed service is offered as an integrated service, it is not possible for consumers to directly recognise a component that causes the service to fail. Collaborating agents use the association between component and composed services to monitor the reliability of the components and identify those that are unreliable.

Aggregation and Optimisation of Trustworthiness of Composite Services

The chapter presents the Aniketos approach to aggregating and predicting the trustworthiness of services that are assembled from component services. Some of the important characteristics of service environments are that they are dynamic, distributed and loosely coupled. These characteristics result in the existence of different levels of functional and non-functional attributes of the services operating in such environments. Consequently, it creates challenges for interacting service consumers that require to only deal with services that are trustworthy. In service compositions, the component services may be mandatory or optional and vary in their contribution to the trustworthiness of the composite service. Composition techniques must be able to select trustworthy components and to dynamically adapt to subsequent changes in the services and the environment. The availability of multiple services providing the same or similar functionality but with different trustworthiness levels helps composite service providers to establish and maintain trustworthy compositions.