1-1
1 DLDP Configuration
z The term switch used throughout this chapter refers to a switching device in a generic sense or the
switching engine of a unified switch in the WX3000 series.
z The sample output information in this manual was created on the WX3024. The output information
on your device may vary.
DLDP Overview
You may have encountered unidirectional links in networking, as shown in Figure 1-1 and Figure 1-2.
When a unidirectional link occurs, the local device can receive packets from the peer device through the
link layer, but the peer device cannot receive packets from the local device. Unidirectional links can
cause many problems, such as spanning tree topology loop.
Device Link Detection Protocol (DLDP) can detect the link status of the optical fiber cable or copper
twisted pair (such as super category 5 twisted pair). If DLDP finds a unidirectional link, it disables the
related ports automatically or informs users to disable them manually according to the configurations, to
avoid network problems.
Figure 1-1 Fiber cross-connection
GE1/0/10 SwitchA GE1/0/11
GE1/0/10 SwitchB GE1/0/11
PC