158NOTE:The Power Stateful Control TLV is defined in IEEE P802.3at D1.0. The later versions no longer support thisTLV. H3C devices send this type of TLVs only after receiving them.LLDP-MED TLVsLLDP-MED TLVs provide multiple advanced applications for voice over IP (VoIP), such as basicconfiguration, network policy configuration, and address and directory management. LLDP-MED TLVsprovide a cost-effective and easy-to-use solution for deploying voice devices in Ethernet. LLDP-MED TLVsare shown in Table 26:Table 26 LLDP-MED TLVsType DescriptionLLDP-MED Capabilities Allows a network device to advertise the LLDP-MED TLVs it supportsNetwork PolicyAllows a network device or terminal device to advertise VLAN ID of thespecific port, VLAN type, and the Layer 2 priorities for specificapplicationsExtended Power-via-MDI Allows a network device or terminal device to advertise power supplycapability. This TLV is an extension of the Power Via MDI TLV.Hardware Revision Allows a terminal device to advertise its hardware versionFirmware Revision Allows a terminal device to advertise its firmware versionSoftware Revision Allows a terminal device to advertise its software versionSerial Number Allows a terminal device to advertise its serial numberManufacturer Name Allows a terminal device to advertise its vendor nameModel Name Allows a terminal device to advertise its model nameAsset IDAllows a terminal device to advertise its asset ID. The typical case isthat the user specifies the asset ID for the endpoint to facilitatedirectory management and asset tracking.Location IdentificationAllows a network device to advertise the appropriate locationidentifier information for a terminal device to use in the context oflocation-based applicationsManagement addressThe management address of a device is used by the network management system to identify andmanage the device for topology maintenance and network management. The management address isencapsulated in the management address TLV.How LLDP worksOperating Modes of LLDPLLDP can operate in one of the following modes:• TxRx mode. A port in this mode sends and receives LLDPDUs.• Tx mode. A port in this mode only sends LLDPDUs.• Rx mode. A port in this mode only receives LLDPDUs.
