To enable the adoption of the IaaS and PaaS services, a change in how the applications are designed and architected needs to be made.
The model of designing enterprise applications on a base platform (read: application server) meant that the heavy lifting of the application's scalability and availability was the responsibility of the platform. Enterprise developers would focus on using the standardized JEE patterns and developing components (Presentation, Business, Data, and Integration) to build fully functional and transactional applications. The extent to which the application could be scaled was limited by the abilities (node clustering and distributed caching) of the underlying platform:
Monolithic application ...
