504 CHAPTER 13: V LAN M ANAGEMENTFigure 260 Example of VLANs Distributed Amongst More Than One SwitchThe Default VLAN A new or initialized switch contains a single VLAN, the default VLAN. ThisVLAN has the following definition:■ VLAN Name — typically Default VLAN or just Default■ 802.1Q VLAN ID — 1 (if tagging required)All ports on the switch are initially placed in this VLAN, untagged.Communication between VLANsCommunication between two different VLANs can only take place if theyare connected to an appropriately configured router or a Layer 3 switch.Alternatively, if the switch containing the VLANs is itself a Layer 3 switchand is configured correctly, it will be able to route the traffic from oneVLAN to the other internally.In an IP environment, communication between VLANs is achieved bydefining VLAN-based IP interfaces on a Layer 3 switch or router.Commonly, each VLAN corresponds to one IP subnet, although it ispossible to have more than one IP subnet per VLAN.For example, a network has two VLANs: one VLAN with ID 2 definesdevices on the subnet 192.168.50.0/255.255.255.0 and another VLANwith ID 3 defines devices on the subnet 192.168.51.0/255.255.255.0.For devices on one VLAN to communicate with devices on the other
