wbamberg/browserid-field-guide — comment on commit 65b7cab3d465d2f8a4761c43f0f98411f25dac4d
File: how_browserid_works.html line 100
By ozten:

Sorry that wasn't very helpful.

I think a diagram more like your openid one communicates who is doing what.

Here is a quick drawing where the user's browser is the center and has a private key. The IdP has the public key. The RP is doing local verification. Some processing is done on the browser and some on the RP (example.com).
http://www.flickr.com/photos/ozten/6392259259/sizes/l/in/photostream/