The chapter presents information on the designs in a format that allows you to try your hand at the designs without yet seeing the way they are presented in the book. I'll note the point in each case study where you can set down the book and make some decisions yourself. Then you can pick the book up and compare your final design with what is presented here.
There are no right or wrong answers here; the point of this chapter is to give you some experience designing secure networks before you go and do it on your own. The sections of the chapter are organized as follows:
This section gives you a basic idea what the organization does and what the basic business requirements of the network are. Some information on IT staffing levels is also included.
This section presents the network as it exists today. In some cases, the network meets the business requirements; in other cases, it does not. In all cases, security improvements must be made. Vulnerabilities in the current network are also highlighted.
This section highlights the new security requirements as they specifically pertain to the network. These requirements are not complete and in most cases simply map business and policy requirements into specific technical requirements.
Here, the overall updated design that meets the business and security requirements for the organization is presented. This step can be completed on your own before looking at the design presented in this book.
Simply having a good security design is just part of the solution. To implement it on a production network, you need specific steps to take that allow the network to migrate to the new design in stages. This section highlights those stages at different levels of detail depending on the complexity of the design. Migrations strategies are discussed in more detail in Chapter 12, "Designing Your Security System."
The attack example section highlights a few key attacks and how the new security system responds to them. Attacks that are both successful and unsuccessful are highlighted.
There can be unique criteria for a design that are called out as appropriate within the individual sections.