Linksys LGS308 User Manual page 89

Voice VLAN CoS
The device can advertise the CoS/802.1p and DSCP settings of the voice VLAN by using LLDP-
MED Network policies. You can create your network policy manually or enable the device to
automatically generate the network policy based on your voice VLAN configuration. MED-
supported devices must send their voice traffic with the same CoS/802.1p and DSCP values, as
received with the LLDP- MED response.
You can disable the automatic update between Voice VLAN and LLDP-MED and use his own
network policies.
Working with the OUI mode, the device can additionally configure the mapping and remarking
(CoS/802.1p) of the voice traffic based on the OUI.
By default, all interfaces are CoS/802.1p trusted. The device applies the quality of service based
on the CoS/802.1p value found in the voice stream.
For Telephony OUI voice streams, you can override the class of service and optionally remark the
802.1p of the voice streams by specifying the desired CoS/802.1p values and using the
remarking option under Telephony OUI.
Voice VLAN Constraints
The following constraints exist:
• Only one Voice VLAN is supported.
A VLAN that is defined as a Voice VLAN cannot be removed.
•
In addition the following constraints are applicable for Telephony OUI:
• The Voice VLAN cannot be VLAN1 (the default VLAN).
The Voice VLAN QoS decision has priority over any other QoS decision, except for the
•
Policy decision.
• A new VLAN ID can be configured for the Voice VLAN only if the current Voice VLAN does
not have candidate ports.
• The interface VLAN of a candidate port must be in General or Trunk mode.
• The Voice VLAN QoS is applied to candidate ports that have joined the Voice VLAN, and to
static ports.
• The voice flow is accepted if the MAC address can be learned by the Forwarding Database
(FDB). (If there is no free space in FDB, no action occurs).
89