PASR: Process-Aware Middleware Framework for Dynamic Service Replacement in SOA

Service-Oriented Architecture (SOA) is a paradigm to achieve growing business needs by offering diverse capabilities on the fly. Often, services from multiple providers are glued together to achieve a specific goal. However, if any of the services involved in a process does not respond in a timely manner, the overall process gets an impact and may lead to an incomplete transaction. In such cases, the service is declared as faulty as it fails to meet one or more of the Quality of Service (QoS) parameters including response time, throughput, and availability. Numerous techniques have been proposed to replace faulty services with appropriate substitutes. However, triggering a replacement may not be suitable for situations where delay in turnaround time is caused by factors that are not under the control of service providers including intranet and route latency. This paper proposes a Process-Aware Service Replacement (PASR) approach for triggering the replacement of faulty services specifically tied to turnaround time. PASR considers the performance of participating services during the execution of a process and triggers a replacement based on user preferences. Furthermore, the proposed technique leverages the ability to switch back to the primary service and avoid the additional overhead incurred with the use of alternate services.

I. Introduction

Service-Oriented Architecture (SOA) is a paradigm for managing and utilizing capabilities that may be developed by an organization under its ownership or by a third party [1]. In order to meet the growing needs, most of the businesses focus on consuming the already available services, thus saving in-house development cost and achieve quick time to market. The core concept in SOA revolves around Web Services. Web services, either SOAP or REST, are a realization of SOA which is said to be an architectural style comprised of services as the main building block [2]. A service is a means by which functionalities are exposed by the providers to fulfill the needs of the consumers; thus, bringing needs and capabilities together [1].