Restrict IP's by code in Asp.net MVC

Question

My server is under attack a DDoS attack so I want to restrict IP's. I know how to detect DDoS in ASP.NET MVC (in ApplicationBeginRequest method), but is there also a way (in ASP.NET) to apply restriction on NIC, Windows Firewall or IIS?

Any ideas?

If I can restrict ip's on NIC level by code I will be a very happy person :)