This chapter answered the question, "What is network access control?" by providing a solution overview as well as taking a look at the individual components that make up NAC. The different implementations of NAC were also explained, including NAC-L3-IP, NAC-L2-IP, and NAC-L2-802.1X. Network-access devices supporting NAC were presented, along with the version of software required.
Looking ahead, subsequent chapters focus on the installation, configuration, and operation of each individual NAC component. Once complete, the individual components are combined to illustrate real-world deployment scenarios in Part III, "Deployment Scenarios." Finally, Part IV, "Managing and Monitoring NAC," focuses on the overall management and monitoring of the NAC solution.