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DLDP CONFIGURATION
When performing DLDP configuration, go to these sections for information you 
are interested in:
■ “Overview” on page 183
■ “DLDP Configuration Task List” on page 190
■ “Enabling DLDP” on page 190
■ “Setting DLDP Mode” on page 191
■ “Setting the Interval for Sending Advertisement Packets” on page 191
■ “Setting the DelayDown Timer” on page 191 
■ “Setting the Port Shutdown Mode” on page 192
■ “Configuring DLDP Authentication” on page 192
■ “Resetting DLDP State” on page 193
■ “Displaying and Maintaining DLDP” on page 193
■ “DLDP Configuration Example” on page 193
■ “Troubleshooting” on page 195
Overview A special kind of links, namely, unidirectional links, may occur in a network. When 
a unidirectional link appears, 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 link can cause problems such as loops in a Spanning 
Tree Protocol (STP) enabled network.
As for fiber links, two kinds of unidirectional links exist. One occurs when fibers 
are cross-connected, as shown in Figure 49. The other occurs when one end of a 
fiber is not connected or one fiber of a fiber pair gets disconnected, as illustrated 
by the hollow arrows in Figure 50.