In the Microsoft ASP.NET 4 Hosting Deployment Guide, it says that you should put a proxy server in place for hosted sites, and firewall all other requests in order to safely host and isolate applications.
It doesn't say what to use to do this. Ideally I'd like features where I could record things like amount of bandwidth used, throttle sites that are using too much etc.
Is there an open source or free proxy that one might typically use for this?