1-2Figure 1-2 Fiber broken or not connectedS w itch BS w itch AP CS w itch BS w itch AP CS w itch BS w itch AP CS w itch BS w itch AP CG E 1 /0/50G E 1 /0 /50G E 1 /0/5 1G E 1/0 /51DLDP provides the following features:z As a link layer protocol, it works together with the physical layer protocols to monitor the link statusof a device.z The auto-negotiation mechanism at the physical layer detects physical signals and faults. DLDPidentifies peer devices and unidirectional links, and disables unreachable ports.z Even if both ends of links can work normally at the physical layer, DLDP can detect whether theselinks are connected correctly and whether packets can be exchanged normally at both ends.However, the auto-negotiation mechanism cannot implement this detection.z In order for DLDP to detect fiber disconnection in one direction, you need to configure the port towork in mandatory full duplex mode at a mandatory rate.z When the port determines the duplex mode and speed through auto-negotiation, even if DLDP isenabled, it does not take effect when the fiber in one direction is disconnected. In this case, the portis considered down.DLDP FundamentalsDLDP ImplementationDLDP detects link status by exchanging the following types of packets.
