Explanation/Reference:
* The Device Link Detection Protocol (DLDP) can detect the link status of a fiber cable or twisted pair.
Upon detecting a unidirectional link, DLDP shuts down the faulty port automatically or prompts the user to do so manually depending on the configuration to avoid forwarding problems.
* As a link layer protocol, DLDP can identify remote devices, detect unidirectional links, and shut down unreachable ports at the link layer.
/ If both ends of a link are operating normally at the physical layer, DLDP detects whether the link is correctly connected at the link layer and whether the two ends can exchange packets properly. This is beyond the capability of the auto-negotiation mechanism at the physical layer.
/In conjunction with the physical layer auto-negotiation mechanism where physical signals and faults can be detected, DLDP can detect and shut down physically/logically unidirectional links.
2 DLDP Implementation
Reference: DLDP Technology White Paper
http://www.h3c.com/portal/Products___Solutions/Technology/LAN/
Technology_White_Paper/200812/623012_57_0.htm