STUDY TIP

While ACLs aren’t a specific exam objective, they’re fundamental in many security implementations and processes. Newer operating system (OS) versions for devices like PIX firewall boxes and Catalyst switches use Cisco IOS�"like features and commands and, therefore, incorporate access list capabilities. Make sure you’re comfortable with how access lists are constructed and how they work. If you need a refresher on ACLs, go to Appendix A.