Establishing isolated security zones within an enterprise network is an effective strategy for reducing many types of risk, and this is especially obvious when one considers how permeable networks are today.  The old perimeter defense model is no longer sufficient.  Some would argue it is no longer necessary — that de-perimeterization is inevitable, we should prepare for a future of blended networks without clear boundaries and security should be moved inward.  Ultimately, all security is about protecting a valuable asset – data – but that protection involves a defense-in-depth strategy that includes all layers. (more…)