SOA stands for Service Oriented architecture which is an architectural paradigm of distributed computing for synchronous and asynchronous applications. I absolutely believe that there are many companies and organizations that cannot change or promote their new business activity due to their old fashioned applications. They want innovate new business lines and have more cooperation with their partners in order to increase their services speed and induce customer to buy more products and services from them. The problem is they do not know how to achieve such computing system. In the large-scale IT environment where the existing applications and legacy systems are working, it is much cost expensive and difficult to develop an adequate computing system from scratch. In such case, developers rather to use proper approach such as SOA to rectify this problem. SOA is able to integrate the existing applications and services to fulfill a new specific business process. With SOA, companies are able to share their data and applications with the partners, costumers and other organizations in order to decrease cost and time of developing.
According to IBM SOA Center of Excellence SOA is defined: “Service Oriented Architecture is an enterprise-scale IT architecture for linking resources on demand. These resources are represented as business-aligned services which can contribute and be composed in a value-net, enterprise, or line of business to complete business needs. The major structuring element for SOA applications is a service as contrast to subsystems, systems, or components”
Service Oriented Architecture (SOA) is not something you can buy in the market and also it is more than an architectural approach that covers technique, practices, and methodology.
In the SOA environment, application’s business logic or individual functions can be exposed as Web services to internal and even external usage. Web services are designed to support interoperable machine-to-machine interaction over an enterprises network. Web service has an interface that describes its specifications into Web service Definition Language (WSDL). It communicates with other services using XML messages based protocol like Simple Object Access Protocol (SOAP). SOA services are stored in a registry which makes able service consumers to look up and invoke that service. It uses Universal Description, Definition, and Integration (UDDI) as a standard to perform its tasks. Due to the loosely coupled nature of SOA, the interface of its services is independent of the implementation. Those Web services can be composed to create new business services without knowing other services’ underlying implementations. Each web Services has a Qos ally with it. The Quality of services (QoS) refers to aspects such as availability, accessibility, integrity, performance, reliability, regulatory, and security.
In conclusion, SOA can help developers and companies to provide a flexible, reusable, and interoperable IT environment and make them easy to maintain in future.