Configuring Security, Quality, and Network Features
Configuring VLAN Settings
Cisco Small Business SPA300 Series, SPA500 Series, and WIP310 IP Phone Administration Guide 164
5
 
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. 
For the Cisco SPA525G/525G2, when the VLAN is changed, the user sees the 
voice component refreshed when IP address is changed. For the Cisco SPA50X, 
the 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.
Wireless LAN Environments
Network policy for the VLAN feature is not supported for wireless networks. The 
Wireless AP or Wireless router must be enabled for LLDP-MED as the Network 
Connectivity Device. The DSCP portion for network policy from Wireless AP/
Router will be supported if enabled.
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.