IEEE 802.1ab Link Layer Discovery Protocol (LLDP) allows network devices to advertise their identity and capabilities to peer devices on a LAN and store information about the network. The stored network information is used to diagnose and troubleshoot any network issues.
LLDP supports a set of attributes with Type-Length-Value (TLV) to discover neighboring devices. The TLV information provides network mapping, inventory, data, and network troubleshooting information.