A switch breaks up collision domains and is a single broadcast domain. So how about breaking the single broadcast domains into multiple ones? VLAN (Virtual LAN) makes this possible and on a single switch we can have multiple broadcast domains. But once you create multiple VLANs on a switch, it becomes tedious to replicate the same configuration on all the other switches. This is where VTP (VLAN Trunking Protocol) comes in. So we have multiple switches with different VLANs and VTP, making management easier. But how do we make a device in one VLAN communicate with a device in another VLAN? We'll cover this in InterVLAN routing.