I\'m working on a .net portal which would be having lots of concurrent users.
so scalability,performance need to be addressed in the design and architecture.
We plan to use load
Do you really need an app server? Just how big are you talking exactly? For example Stackoverflow.com has ~50k uniques a day and doesn't have an app server so I assume you are talking much bigger than that? Most performance bottle necks come down to database issues so I would concentrate on that.