Operation Manual – DLDPH3C S7500 Series Ethernet Switches Chapter 1 DLDP Configuration1-2SwitchBSwitchAPCGE2/0/3GE2/0/3 GE2/0/4GE2/0/4SwitchBSwitchAPCGE2/0/3GE2/0/3 GE2/0/4GE2/0/4dFigure 1-2 Fiber broken or not connecteDLDP provides the following features:z As a link layer protocol, it works together with the physical layer protocols tomonitor the link status of a device.z The auto-negotiation mechanism at the physical layer detects physical signals andfaults. DLDP identifies peer devices and unidirectional links, and disablesunreachable ports.z Even if both ends of links can work normally at the physical layer, DLDP can detectwhether these links are connected correctly and whether packets can beexchanged normally at both ends. However, the auto-negotiation mechanismcannot implement this detection.Note:z In order for DLDP to detect fiber disconnection in one direction, you need toconfigure the port to work 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 is enabled, it does not take effect when the fiber in one direction isdisconnected. In this case, the port is considered down.1.2 DLDP Fundamentals1.2.1 DLDP ImplementationDLDP detects link status by exchanging the following types of packets.
