154 CHAPTER 7: CONFIGURING VLANS
Defining Voice 
VLAN
Voice VLANs allows network administrators enhance VoIP service by 
configuring access ports to carry IP voice traffic from IP phones on specific 
VLANs. Network Administrators can configure VLANs on which voice IP 
traffic is forwarded. Non-VoIP traffic is dropped from the Voice VLAN. 
Voice VLAN also provides QoS to VoIP, ensuring that the quality of sounds 
does not deteriorate if the IP traffic is received unevenly. The system 
currently supports one voice VLAN. 
When configuring Voice VLAN, ensure the following: 
■ IP phones are configured with VLAN-mode as enabled, ensuring that 
tagged packets are used for all communications. 
■ If the IP phone’s VLAN-mode is disabled, the phone uses untagged 
packets. The phone uses untagged packets while retrieving the initial 
IP address through DHCP. The phone eventually use the Voice VLAN 
and start sending tagged packets. 
The Voice VLAN Page contains the following fields: 
To configure Voice VLANs: 
1 Click Policy > Voice VLAN. The Voice VLAN Page opens:
Figure 76   Voice VLAN Page
The Voice VLAN Page contains the following fields: