CCNA 200-301 Official Cert Guide Library, 2nd Edition

Chapter 8

Applied IP ACLs

This chapter covers the following exam topics:

5.0 Security Fundamentals

5.6 Configure and verify access control lists

When you plan a real IP ACL to enable in a production network, the task often becomes large and complex. For instance, imagine you rely on the implied deny any logic at the end of the ACL. In doing so, your ACL must include permit commands matching all traffic you want to allow; otherwise, the ACL denies (discards) those packets. If you add a permit ip any any command to the end of your extended ACL, making the default to permit traffic, you have the opposite problem: you need to work hard to identify everything you want to deny and match that in your ACL. The complexities increase with multiple network ...