Dell POWERCONNECT 6200 SERIES Configuration Manual

Also see for POWERCONNECT 6200 SERIES: Getting started guide Getting started guide

Contents

38 Switching Configuration• When a dot1p priority is associated with the Voice VLAN port instead of a VLAN ID, then the priorityinformation is passed onto the VOIP phone using the LLDP-MED mechanism. By this method, thevoice data coming from the VOIP phone is tagged with VLAN 0 and with the exchanged priority; thusregular data arriving on the switch is given the default priority of the port (default 0), and the voicetraffic is received with a higher priority.You can configure the switch to override the data traffic CoS. This feature can override the 802.1 priority ofthe data traffic packets arriving at the port enabled for Voice VLAN. Therefore, any rogue client that is alsoconnected to the Voice VLAN port does not deteriorate the voice traffic.Interaction with LLDP-MEDThe interactions with LLDP-MED are important for Voice VLAN:• LLDP-MED notifies the Voice VLAN component of the presence and absence of a VoIP phone on thenetwork.• The Voice VLAN component interacts with LLDP-MED for applying VLAN ID, priority and taginformation to the VoIP phone traffic.For release 2.0 and earlier, the Voice VLAN feature can only be used by IP phones that support LLDP-MED,e.g. 4610SW Avaya phones.Example#1: Configuring Voice VLANThe commands in this example create a VLAN for voice traffic with a VLAN ID of 25. Then, Voice VLAN isadministratively enabled on the switch. Finally, port 1/g12 is set to an 802.1Q VLAN and then enabled forVoice VLAN traffic.console#configureconsole(config)#vlan databaseconsole(config-vlan)#vlan 25console(config-vlan)#exitconsole(config)#voice vlanconsole(config)#interface ethernet 1/g12console(config-if-1/g12)#switchport mode generalconsole(config-if-1/g12)#voice vlan 25console(config-if-1/g12)#exitconsole(config)#exitconsole#show voice vlan interface 1/g12Interface...................................... 1/g12Voice VLAN Interface Mode...................... EnabledVoice VLAN ID.................................. 25Voice VLAN COS Override........................ FalseVoice VLAN Port Status......................... DisabledVoice VLAN Authentication...................... Enabled