I'm looking to create a custom authentication model for my MVC app but I'm not sure where to implement my custom IPrincipal and IIdentity classes. I don't want to do this in the Global.asax on every request as not all the pages in the site will need authentication. So my question is where? Should I be doing this in my custom action filters for the actions that require the user to be logged in?
I don't wish to use the Membership Provider or Forms Authentication this needs to be completely custom and separated.