The highest-level part of the design process is also the most exciting: designing the application architecture. In this stage, the application begins to come to life, without bogging you down in technical details. You create a logical design for your application and then map the logical layers to physical servers. Once you determine the physical layout, you can choose inter-application communication mechanisms to expose your business logic to different front-end user interfaces (UIs) and determine your authentication, authorization, and cryptographic requirements.
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