Acing the CCNA Exam, Volume 1

12 VLANs

This chapter covers

• How to divide a switch into multiple virtual switches with VLANs
• How to configure trunk ports to carry traffic in multiple VLANs
• Routing between VLANs with a router or multilayer switch

In chapter 11, we covered subnetting, which allows us to divide a network into smaller subnets. This is an example of network segmentation—the division of a network into smaller parts. Virtual LANs (VLANs, pronounced “V-LANs”), the topic of this chapter, can be likened to subnets in that they also allow us to divide up a network into smaller parts. With VLANs, we can divide a LAN (a broadcast domain) into smaller LANs, called VLANs. Whereas subnets allow us to segment the network at Layer 3, VLANs allow us to segment the network ...