When preparing for any Network Certification Exam, one of the first topics that you’ll learn about are Access Control Lists (ACLs). Every document or Certification-related book I’ve ever read introduces students to ACLs from the perspective of IPv4 Access-Lists. Sometimes MAC Access-Lists are also mentioned briefly, but only to let the reader know they exist as another type of ACL. Rarely are any details given about how MAC ACLs actually work, or what their significant limitations are.
A key to the mastery of a CCENT-level of networking knowledge is to intimately understand the use of Layer 2 and Layer 3 addressing when two hosts communicate on the network. This blog post will detail how these addresses are used during the network communications between two host devices (Personal Computers, PCs). Here is the topology that will be used in this example: