Defense in Depth

When creating your strategy for securing information on your systems and in your network, always remember to plan for a layered security approach. A useful tool for identifying different layers of security is the OSI network model, displayed using the infographic below.

http://securityblog.s21sec.com/2009/06/attacks-on-layer-two-of-osi-model-i.html

While the OSI model only includes seven layers, there is one missing. Layer 8, which may be the most difficult to secure, is often referred to as the "Political Layer" or, to use a more recent term "Meatspace." Each layer in the model has unique challenges and tools for security, and each type of attack has some well known examples of successful break-in. In future blog posts, we'll discuss some of the attacks directed at specific layers, and some of the tools and techniques for combating those attacks.