Cisco 8831 Administration Manual page 49

Chapter 4 Configure Security, Quality, and Network Features
Configure VLAN Settings
QoS Resolution for LLDP-MED
If CoS is applicable and if CoS=0, the default will be used for the specific extension as previously
described. But the value shown on L2 Priority for TLV for outgoing LLDPDU is based on value used for
extension 1. If CoS is applicable and if CoS != 0, CoS will be used for all extensions.
If DSCP (mapped to ToS) is applicable and if DSCP=0, the default will be used for the specific extension
as previously described. But the value show on DSCP for TLV for outgoing LLDPDU is based on value
used for the extension 1. If DSCP is applicable and if DSCP != 0, DSCP will be used for all extensions.
If the VLAN > 1 and VLAN < 4095, the VLAN is set accordingly. CoS and ToS are based on the default
as previously described. DSCP is applicable.
If there is a valid network policy for voice application from LLDP-MED PDU and if the tagged flag is
set, the VLAN, L2 Priority (CoS) and DSCP (mapped to ToS) are all applicable.
If there is a valid network policy for voice application from LLDP-MED PDU and if the tagged flag is
not set, only the DPSC (mapped to ToS) is applicable.
The conference phone reboots and restarts the fast start sequence.
Co-Existence with CDP
If both CDP and LLDP-MED are enabled, the network policy for the VLAN is determined by the last
policy set or changed with either one of the discovery modes. If both LLDP-MED and CDP are enabled,
during startup, the phone sends both CDP and LLDP-MED PDUs at the same time.
Inconsistent configuration and behavior for network connectivity devices for CDP and LLDP-MED
modes could result in an oscillating rebooting behavior for the phone due to switching to different
VLANs.
If the VLAN is not set via CDP and LLDP-MED, the VLAN ID that is configured manually is used. If
the VLAN ID is not configured manually, no VLAN will be supported. DSCP is used and the network
policy is determined by LLDP-MED if applicable.
LLDP-MED and Multiple Network Devices
If the same application type is used for network policy but different Layer 2 or Layer 3 QoS Network
policies are received by the phones from multiple network connectivity devices, the last valid network
policy is honored. To ensure deterministic and consistent of Network Policy, multiple network
connectivity devices should not send out conflicting network policies for the same application type.
LLDP-MED and IEEE 802.X
The phones do not support IEEE 802.X and will not work in a 802.1X wired environment. However,
IEEE 802.1X or Spanning Tree Protocols on network devices could result in delay of fast start response
from switches.
Cisco Unified IP Conference Phone 8831 for Third-Party Call Control Administration Guide
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