The voice VLAN feature enables access ports to carry IP voice traffic from an IP phone. When a switch is connected to a Cisco IP phone, the IP phone sends voice traffic with Layer 3 precedence and Layer 2 class of service (CoS) values, which are both set to 5 for voice traffic; all other … Read more
By default, only hosts that are members of the same VLAN can communicate. To change this and allow inter-VLAN communication, you need a router or a layer 3 switch. I’m going to start with the router approach. To support ISL or 802.1Q routing on a Fast Ethernet interface, the router’s interface is divided into logical … Read more
It may come as surprise to you, but configuring VLANs is actually pretty easy. Figuring out which users you want in each VLAN is not; it’s extremely time-consuming. But once you’ve decided on the number of VLANs you want to create and established which users you want to belong to each one, it’ time to … Read more
Most of the time, VLANs are created by a sys admin who proceeds to assign switch ports to each VLAN. VLANs of this type are known as static VLANs. If you don’t mind doing a little more work when you begin this process, assign all the host devices hardware addresses into a database so your … Read more
The following figure shows how layer 2 switched networks are typically designed as flat networks. With this configuration, every broadcast packet transmitted is seen by every device on the network regardless of whether the device needs to receive that data or not. By default, routers allow broadcasts to occur only within the originating network, while … Read more