Specifications

Engineering Guidelines
320
The information advertised by LLDP-MED is obtained from various switch settings. These
settings need to be configured in order to get the correct information on the relevant port. Note
that some of these commands are used for other functions, which includes the policy
enforcement, some of which operate on a VLAN or switch level, not just at the port.
These areas are highlighted in the diagram below, and described in more detail in the following
sections.
The shaded areas identify the end devices and areas linked with policy enforcement through
the Access Layer Switch. Information from a number of areas is used to identify the service, in
this case, voice, which is combined to create the LLDP/LLDP-MED advertisement.
Figure 58 identifies that the end device will use VLAN tagging, in this case VLAN 63, will use
Priority 6 and DSCP value 46 (101110), commonly referred to as Expedited Forwarding. These
values are used throughout this Appendix to illustrate network switch settings and
configurations.
By default, LLDP and LLDP-MED are enabled across the switch. LLDP-MED requires that the
voice VLAN be identified at a port before the port becomes active in advertising of VLAN, Priority
and DSCP.
Figure 58: LLDP-MED Advertisement Information Sources