How should my team decide between 3-tier and 2-tier architecture?

Question

My team is discussing the future direction of our projects. Half of the team believes in pure three-tier architecture, while the other half believes in two-tier architecture.

Project Assumptions:

• Enterprise Business Applications
• Business logic required by user and database
• Data Validation Required
• Service-oriented (prefer RESTful services)
• Multi-Year Service Plan
• Support for hundreds of users.

3-level commands:

• Permanent layer <==> Domain level <==> UI level
• A service boundary between at least a constant layer and a domain layer. A domain level may have a service boundary between it.
• Transfers between each layer (pure DTO separation)
• , ,

2- :

• Entity Framework + WCF < == >
• -, WCF
• -

. ? ?

Answer 1

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YMMV.

Answer 2

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