Is n-tier software part of the SOA subset?
no. This is not true.
SOA is a design strategy for the enterprise. There are many emails about this being elsewhere, however it addresses how systems interact with the use of services.
The N-tier software architecture is application specific. It helps maintainability and scalability by separating layers of code.
They target different components of information technology and have different goals and benefits.
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No.
For starters, N-Tier is older than SOA, and they are completely different concepts.
The N-tier architecture breaks the application down into separate layers with care to solve. Layers should allow minimal application rewriting if, for example, the frontend changes from a Windows application to a web application.
SOA is a broader concept that attempts to encapsulate individual business services and expose them to each other through a negotiated contract. These individual services can be built using the N-tier architecture.
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