Software as a Service operation model in cloud based ERP systems
István Orosz, Attila Selmeci, Tamás Orosz · 2019
The operation model for cloud-based application has already became the new standard in ERP implementations. The model has introduced a new software abstraction layer, which hides the data center model from the customers. This layer covers the architecture, operating system, database and elements. When the layer covers the complexity of the middleware layers, allows the owners to concentrate on implementing the core business logic only. The risk is usually that more and more resources are allocated to the infrastructure; with this model the resources can be balanced with the business side. In the end this will lead to extended application lifecycle, while the core functions of the business logic are totally separated from the recently changing infrastructure layer. Standard merge and release management, starting from pre alpha state and describes the way until the gold release, was changed in this operational model with an agile way release process. This results the overall possibility of always using the latest version of the application always, when using the Software as a Service cloud model. Code refactoring, reusability is a key factor, as having another abstraction layer between the platform specific and the platform independent model. Having the proper abstract transformation layer between these two keeps the application roles separated, and the end user does not have to create a whole IT support organization, because the abstract layer will hide the low level infrastructure. This article focuses mainly to the change management questions which arise when an organization moves from standard data center solution to a cloud based (SaaS) model.The ERP solutions should be redesigned, reconstructed and sometimes rebuilt from scratch to provide continuous versioning, and be able to offer customer services. As the goal is always to be able to provide services at a lower operational cost there must be a solid reusability method in the application. Code refactoring and reusability methods should be changed also, using and implemented on a separated abstraction layer. The transformation layer has to be able to maintain the goals of the reliability of the software product during its whole lifecycle. These middleware layer have to be able to maintain the reusability of the 3rd party software elements, but the commonly used parts have to be in the same format as in the base application.The article shows different ways and possibilities which all can be used for building up an application environment in the cloud using software as a service and the other different service bus like methodologies, and focuses on switching the operation model from the on premise datacenter application to the cloud based SaaS model.