Recently I was talking with Rocky Lhotka and he said something interesting:

“Just when we got good at Client-Server, they switched things and had us doing n-Tier applications.  Just when we got good at n-Tier development, internet applications took off.”

In my opinion he is right. It is interesting because client-server and n-Tier applications still exist, especially in enterprise development.  I think we’re good at client-server and n-Tier.  The problem is that I think that much of browser based development attempts to apply n-Tier development.

What do I mean?  In simple words, the web server is the middle tier.   The browser is the client tier.

The idea behind n-Tier development is being able to separate the data work into a tier that can be scaled out.  Luckily we know how to scale out webservers (into farms).  Since we are securing webservers, we can isolate security issues from the client…just like we’ve done in n-Tier development.