An access control list (ACL), with respect to a computer file system, is a list of permissions attached to an object. An ACL specifies which users or system processes are granted access to objects, as well as what operations are allowed on given objects. Each entry in a typical ACL specifies a subject and an operation. For instance, if a file has an ACL that contains (Alice, delete), this would give Alice permission to delete the file. It includes the following topics

• IP Access Control Lists
• IP Standard ACL their configuration sequence numbers and wildcard masks
• Extended IP access control lists and configuration
• Named IP Access Lists
• Controlling Telnet and SSH Access with ACLs
• Reflexive Dynamic and Time Based Access Lists
• IP Routing troubleshooting by ping and traceroute commands
• VLSM and ACL issues