Why is .NET Framework 4 split into two pieces?

Question

Does anyone know why the .NET Framework version 4 is split into Client Profile and Extended?

Microsoft cites two reasons for having the Client Profile >

Can be serviced separately.

Does not need the .NET Framework 4 Extended component of the .NET Framework.

These seem flimsy at best to me, and I need to explain why I want both Client Profile and Extended installed on all our client desktops. My best answer now is "I don't know even know why Microsoft split them in the first place"

Answer 1

The client profile began with .Net 3.5sp1. At this point, .Net had grown huge: (as much as 350Mb for common deployments, though 60Mb and 230Mb were more common)... large enough that deployment over the web was often slow and cumbersome. So for sp1 they introduced a client profile. This worked from a technical standpoint. They are able to successfully distribute only a portion of the framework, and developers can safely target just that portion of the framework. Unfortunately, for 3.5 the client profile failed to reduce the deployment size in a meaningful way. Yes, the client profile was smaller, even a lot smaller, but it was still too large to work well with web deployment scenarios.

Now with .Net 4, the client profile is down closer to 50Mb. That's still kinda large, but this new size, combined with increased average broadband speeds, is much more reasonable.

Answer 2

Does your client application actually need the "full" framework? If not, only install the client part - which will be considerably smaller. That's the point of having the separate profile; it's a smaller install footprint and download time for applications which only use the parts of the framework typically required by client apps.

Answer 3

Because Client Profile is easier to load, and contains the common features for client applications only.

It's easy to understand that the programs will load and run faster and you'll occupy less memory.