This has been a short introduction to how SDI can help you secure your network. We have covered how the implementation of SDI has changed in Windows Vista. SDI, as a security technology, is remarkably static. The concept itself is actually one of those timeless pieces of solid engineering that is invariant with platforms. As new platforms come along, the actual ports that need to be opened change, and the mechanism to do it with varies a bit. However, the core goal of allowing only the traffic you absolutely need in your network does not change. It is one of the most valuable, and most underused, security technologies available today. Do not overlook the tremendous potential it has for helping you protect your network.