Migration of Legacy Software to SOA (Service Oriented Architecture) environments

Posted by Isharose on February 27th, 2018

A service-oriented architecture (SOA) is a type of software design where services are provided to the other components by application components, through a communication protocol over the network. The basic principles of service oriented architecture are independent of vendors, products and technologies.

Service-oriented architectures include the following features; SOA services have self-describing interfaces in platform-independent XML documents, SOA services communicate with messages formally defined through XML Schema and SOA services are maintained in the enterprise by a registry that acts as a directory listing.

The legacy systems are migrated by the following approaches like direct migration and indirect migration. It consists in wrapping an alegacy system with a software layer that exposes the original system programs as Web Services. This is known to be cheap and fast, but it has the disadvantage that the legacy system is not replaced by a new one. This service architecture can provide business rules engine and that allows business rules to be incorporated in a service. It also provides a service management infrastructure that manages services and activities like auditing, billing, logging etc. Service-oriented architecture differs from the existing distributed technologies. Which enables changes to the applications while keeping clients or service consumers isolated from evolutionary changes that happen in the service implementation.

An important feature is the recognition that the assets perform services, and the development of software that provide access to the assets,  which have interfaces that are in the same form as the interfaces to other software services of the enterprise. SOA service can be implemented either in .Net or J2EE, and the application consuming the service can be on a different platform or language.