Learn Cisco Network Administration in a Month of Lunches

Chapter 6. Managing virtual LANs (VLANs)

Recall from chapter 2 that you need to keep broadcast domains small to avoid network performance problems like flooding and interrupts. On a large network, this brings with it the nasty side effect of having to split devices into separate broadcast domains.

But separating broadcast domains isn’t just about necessity, nor is it a concern for only large networks. Many organizations—even small ones—want to maintain separate broadcast domains for security. For example, a company may want to keep computers in the Human Resources department in a separate broadcast domain from computers in the Marketing department.

In chapter 2, I illustrated one way to achieve such a configuration using two separate, disconnected ...