Microsoft Dynamic IP Restrictions for IIS 7.0 has reached Beta 2. IT professionals and administrators working for hosting companies can leverage DIPRE for IIS in order to both mitigate and block Denial of Service Attacks. The module is completely configurable and integrates seamlessly with IIS 7.0 Manager, and can help fend off not just DoS attacks but also password cracking attempts involving Brute-force.
The extension will effectively block Internet Protocol (IP) addresses of HTTP clients associated with certain patterns, normally conducive of attack attempts.
For more details on the release make sure you check updated article on using Dynamic IP Restrictions.