Ports 1 through 10 are assigned to the voice VLAN and this configuration is suitable for stand-alone IP phones and video devices that connect to the Ethernet switch.

Switch> enable                                      change from user to privilege mode
Switch # configure terminal                     change to global config mode
Switch(config)# vlan 20 name v20               create vlan 20 for voice traffic
Switch(config)# int range fa 0/1 - 10            context for ports 1 through 10
Switch(config)# des “IP phones with no
PCs attached”                                Description of ports’ use
Switch(config)# switchport access vlan 20 change native/port vlan from data (vlan-1) to voice (vlan-20)
Switch(config)# no cdp enable                  disable CDP for ports 11-20 (remove proprietary protocols)
Switch(config)# spanning-tree portfast        place ports in forwarding mode immediately
Switch(config)# spanning-tree bpduguard
enable                                      enable bpdu guard in case of a layer-2 loop


Ports 12 through 20 are assigned to the voice vlan and this config is suitable for IP phones and video devices that have a PC attached to them..

Switch(config)# int range fa 0/11 – 20           context for ports 11 through 20
Switch(config)# des “IP phones with PCs 
attached”                                       description of ports’ use
Switch(config)# speed 100                             lock port speed to 100-Mbps (optional setting to Auto-Neg)
Switch(config)# duplex Full                         lock port duplex to Full (optional setting to Auto-Neg)
Switch(config)# switchport voice vlan 20         config implicit trunk for IP phones or video endpoints
Switch(config)# no cdp enable                       disable CDP for ports 11 through 20
Switch(config)# spanning-tree portfast            place ports in forwarding mode immediately
Switch(config)# spanning-tree bpduguard enable enable bpdu guard in case of a layer-2 loop


These commands create a trunk (more than one vlan) to take voice and data traffic to a router.

Switch(config)# int fa 0/48                         context for port 48
Switch(config-if)# des “Uplink trunk to
router R1”                                       description of port usage
Switch(config-if)# switchport trunk encap
dot1q                                             define port 48 as a data trunk using 802.1Q
Switch(config-if)# switchport mode trunk        enable trunking mode
Switch(config-if)# switchport nonegotiate        trunk port 48 will not negotiate a trunk status with the
                                               other end of the link
Switch(config-if)# switchport trunk allowed
vlan remove 2-19,21-4094                           remove unneeded vlans