The "one-half" kind of platform on the Internet

My friend Bill asked my opinion today on the excellent article from Marc Andreessen -- The three kinds of platforms you meet on the Internet.

I replied via email, but then thought this dried up blog of mine may get a few words as well. So, here is the quote.

What can I say? It's a very nice classification attempt-slash-summary, a good place to refer somebody to, etc. I enjoyed reading it.

But I think he may be wrong in presuming a strong separation between clients and servers. In his view the only true platform is that in which a "server" somewhere either runs the user code (level 3) or it does not (levels 1/2). If we include the browser into the mix as a full member the picture becomes a much more interesting and complex one. Security aside it's possible to imagine an application that pulls its parts from various sources (either through some browser extension for "trusted" JS sources or through a platform-registered proxy of some kind or through a greasemonkey-like mechanism) and then executes on the client/browser. It instantly achieves full "Level 3" platform status -- there is virtually no cost for developer and the code runs in the same space as the "core" platform code. At the same time it's much easier to provide on the "platform" developer side -- less security/throttling/fairness overhead.

That's what I think.

Andrew.