TSA is a reaction to the bloat and complexity in todays web application frameworks.

TSA proposes to remove all presentation layer logic from the server to JavaScript (or other) logic on the client (Web Browser).

This result in three positive things;

1. The server-side developer can focus on the business logic
2. The application becomes less complex as the client is developed separately.
3. Communication between server and client use a protocol, which can be used to export, import or present data to other, or future system (SOA).
   

SOFEA stands for Service-Oriented Front-End Architecture.

The fundamental principle in SOFEA is the decoupling of the three orthogonal Presentation Tier processes of Application Download, Presentation Flow and Data Interchange.

Presentation Flow is driven by the client, not by any server-side component.

Server-side components are only concerned with business logic, in the form of exposed services. This is why SOFEA is a Service-Oriented Front-End Architecture.