A Compendium on Service Oriented Architecture and Service Level Agreements

Abstract

ABSTRACT Service Oriented Architecture provides an effective application integration and on-demand services provision. It supports loose coupling structure of the services which provides effective service management and also effective usage of the existing services. SOA gives strong support to business Innovation if implemented properly with proper understanding of the Principles of SOA. In order to incorporate the effective SOA, there should be a thorough deployment of the SOA, the SLA metrics needs to be standardized and focused. Since, the reliability of any service depends on the successful functionality. This article studies and reviews on a broad spectrum the Service Oriented Architecture and its Service Level Agreement (SLA) and its basic metrics. Keywords SOA, SLAs of SOA, Metrics of SLA in SOA, SLA Mon Tools 1. INTRODUCTION The SOA is an application architectural concept that defines the use of services to support business requirements. In SOA, the resources are made available as independent services, which can be accessed in a standardized manner. The Services are loosely coupled in order to facilitate the usage of the existing services and the components are reusable. In SOA environment, the Service Level Agreement (SLA) refers to mutually agreed understandings and expectation focused as the evaluation criteria for Quality of Service, between the Service Provider and Service Consumers. As the Services become more flexible, the Quality of Services becomes more critical and important. Every user is concerned about the Quality of Service. Thus there is a huge necessity of defining the QoS Metrics during the contract between the Service Providers and the Service Consumers, which would prove useful in making the Service transaction execute smoothly and efficiently [1]. More and more Services are done in order to create larger business process and services with the SOA developments [2], [3]. This initiates a closer examination of the quality of the services. The traditional mechanism makes it difficult to adapt to the complexity in open networked environment. The SLA is the contractual basis between the customer and the Service Provider about the Product. The Service of SOA is managed by SLA hence the Service Management can be achieved by the effective SLA management. In a Complex network environment requirements of end-to-end Quality of Service are different. The use of SLA guarantees in product can make the network more customer-focused. Further SLA based services are becoming a requirement to the provisioning of IP based network services to ensure Quality of Service. The Technical component of SLA is made up of a number of negotiated Service Level Objectives (SLO) which is based on Key Performance Indicators (KPI) metrics and Key Quality Indicators (KQI).