1-5Type DescriptionManufacturer Name Allows a MED endpoint to advertise its vendor name.Model Name Allows a MED endpoint to advertise its model name.Asset IDAllows a MED endpoint 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 location identifierinformation for an endpoint to use in the context of location-basedapplications.See the IEEE standard (LLDP) 802.1AB-2005 and the LLDP-MED standard (ANSI/TIA-1057) for moreinformation about LLDPDU TLVs.Management 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.Operating Modes of LLDPLLDP can operate in one of the following modes:z TxRx mode. A port in this mode sends and receives LLDPDUs.z Tx mode. A port in this mode only sends LLDPDUs.z Rx mode. A port in this mode only receives LLDPDUs.z Disable mode. A port in this mode does not send or receive LLDPDUs.Each time the LLDP operating mode of a port changes, its LLDP protocol state machine re-initializes. Toprevent LLDP from being initialized too frequently at times of frequent operating mode change, aninitialization delay, which is user configurable, is introduced. With this delay mechanism, a port mustwait for the specified interval before it can initialize LLDP after the LLDP operating mode changes.How LLDP WorksTransmitting LLDPDUsAn LLDP-enabled port operating in TxRx mode or Tx mode sends LLDPDUs to its directly connecteddevices both periodically and when the local configuration changes. To prevent the network from beingoverwhelmed by LLDPDUs at times of frequent local device information change, an interval isintroduced between two successive LLDPDUs.This interval is shortened to 1 second in either of the following two cases:z A new neighbor is discovered, that is, a new LLDPDU is received carrying device information newto the local device.z The LLDP operating mode of the port changes from Disable/Rx to TxRx or Tx.
