Other tips in this series have examined the seven-layer OSI model from the perspective of security. Although security was not the No. 1 goal of the designers of the OSI model, the idea behind these tips was to highlight the importance of adding security at each layer to get the reader to consider the concept of defense in depth. Now that we have completed the seventh layer, some may think we are through. The OSI model is a framework for data communications, but does security stop there? No, there is the mythical eighth layer. While not included in the OSI model, this human layer does exist. The eighth layer is the layer at which technology interfaces with people. The eighth layer deals with people and policies. Let's begin by talking about people.