LLDP Overview
LLDP is a standard link-layer protocol. An LLDP-capable device encapsulates main device information into LLDP packets and sends the LLDP packets to its neighbors. When receiving the LLDP packets, neighbors save the information carried in the LLDP packets to the management information base (MIB). The NMS queries and determines link status based on information in the MIB.
The network scale develops quickly, network device types are increasing, and their configurations are complicated. The NMS is required to have more functions and higher processing capability. The traditional NMS can only analyze Layer 3 network topologies and cannot obtain details about the Layer 2 network topology or detect configuration conflicts. To overcome this limitation, a standard Layer 2 information exchange protocol is needed.
The LLDP protocol provides a standard link-layer discovery method. This protocol can obtain Layer 2 information about network devices to help quickly detect configuration conflicts and faults on the network. Users can use the NMS to monitor link status of LLDP-enabled devices and quickly locate faults on the network.