The layers are needed to maximize the loose coupling between applications and data in order to create reusable services for a flexible on-demand enterprise.
这些层需要最大化应用程序与数据之间的松散耦合，以便为灵活的随需应变企业创建可重用的服务。
2
This enables faster and more flexiblecoupling and decoupling of applications.
这允许实现更快和更灵活的应用程序耦合和分离。
3
The advantage of this is that such environments are more flexible, without tight coupling between various parts of the overall system.