Kosala Yapa Bandara

Integrated Constraint Violation Handling for Dynamic Service Composition

Dynamic service composition is suitable for on-demand business requests. For autonomic computing, service composition needs to deal with runtime environment faults, but also with business constraint violations which result from business requirements. We propose an approach for integrated handling of business constraint violations and runtime environment faults for dynamic service composition.We introduce a loosely coupled implementation architecture to maintain the platform-independent nature.

Process as a Service Distributed Multi-tenant Policy-Based Process Runtime Governance

With the emergence of Business Process Outsourcing and Cloud Computing, enterprises are looking for available business processes outside of their organizations to quickly adopt to new business requirements and also reduce process development and maintenance costs. The process execution needs to be governed as policy enforcement might differ between different clients. Since a process is deployed outside of the organizations and serves multiple process clients, distribution and multi-tenancy have become two requirements for runtime governance of service processes. We address this problem by introducing a policy-oriented aspectual business process framework. The runtime governance from process clients are integrated as aspects through dynamic weaving into process execution.

Ontology-Based Composition and Matching for Dynamic Service Coordination

Service engineering needs to address integration problems allowing services to collaborate and coordinate. The need to address dynamic automated changes - caused by on-demand environments and changing requirements - can be addressed through service coordination based on ontology-based composition and matching techniques. Our solution to composition and matching utilises a service coordination space that acts as a passive infrastructure for collaboration. We discuss the information models and the coordination principles of such a collaboration environment in terms of an ontology and its underlying description logics. We provide ontology-based solutions for structural composition of descriptions and matching between requested and provided services.

Constraint Integration and Violation Handling for BPEL Processes

Autonomic, i.e. dynamic and fault-tolerant Web service composition is a requirement resulting from recent developments such as on-demand services. In the context of planning-based service composition, multiagent planning and dynamic error handling are still unresolved problems. Recently, business rule and constraint management has been looked at for enterprise SOA to add business flexibility. This paper proposes a constraint integration and violation handling technique for dynamic service composition. Higher degrees of reliability and fault-tolerance, but also performance for autonomously composed WS-BPEL processes are the objectives.

An extended ontology-based context model and manipulation calculus for dynamic Web service processes

Services are offered in an execution context that is determined by how a provider provisions the service and how the user consumes it. The need for more flexibility requires the provisioning and consumption aspects to be addressed at run-time. We propose an ontology-based context model providing a framework for service provisioning and consumption aspects and techniques for managing context constraints for Web service processes where dynamic context concerns can be monitored and validated at service process run-time. We discuss the contextualisation of dynamically relevant aspects of Web service processes as our main goal, i.e. capture aspects in an extended context model. The technical contributions of this paper are a context model ontology for dynamic service context and an operator calculus for integrated and coherent context manipulation, composition and reasoning. The context model ontology formalises dynamic aspects of Web services and facilitates reasoning. We present the context ontology in terms of four core dimensions—functional, QoS, domain and platform—which are internally interconnected.

Ontology-based composition and matching for dynamic cloud service coordination

Recent cross-organisational software service offerings, such as cloud computing, create higher integration needs. In particular, services are combined through brokers and mediators, solutions to allow individual services to collaborate and their interaction to be coordinated are required. The need to address dynamic management - caused by cloud and on-demand environments - can be addressed through service coordination based on ontology-based composition and matching techniques. Our solution to composition and matching utilises a service coordination space that acts as a passive infrastructure for collaboration where users submit requests that are then selected and taken on by providers. We discuss the information models and the coordination principles of such a collaboration environment in terms of an ontology and its underlying description logics. We provide ontology-based solutions for structural composition of descriptions and matching between requested and provided services.

A Coordination Space Architecture for Service Collaboration and Cooperation

With software services becoming a strategic capability for the software sector, service engineering needs to address integration problems based on support that helps services to collaborate and coordinate their activities. The increasing need to address dynamic and automated changes - caused by on-demand environments and changing requirements - shall be answered through a service coordination architecture based on event-based collaboration. The solution is based on a service coordination space architecture that acts as a passive infrastructure for event-based collaboration. We discuss the information architecture and the coordination principles of such a collaboration environment.

A distributed architecture for policy-customisable multi-tenant processes-as-a-service

Service-based business processes are often developed and deployed by single organisations. In distributed, shared resource environments like the cloud on the other hand, consumers share resources owned by cloud providers. This requires multi-tenancy capability for service processes that provide customised behaviour on shared process implementations to meet the varying needs of different process consumers as tenants of the process resource. In this paper, we define a distributed multi-tenant architecture for Business Process Execution Language (BPEL) processes provided as a service. A single-version BPEL process is deployed by a provider and offered for all process consumers, combined with a customisation and management functionality to create a unique experience for different consumers (process tenants). We provide two core components: a policy model for consumers to express customisation/business requirements of service processes and a coordination framework for policy enforcement between consumers and providers to achieve on-the-fly customisation of service processes.