3Com Switch 4500 Family Manual page 176

When you use the dldp enable/dldp disable command in system view to enable/disable DLDP on all
optical ports of the switch, the configuration takes effect on the existing optical ports, instead of those
added subsequently.
Examples
# Enable DLDP on all optical ports of the switch.
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] dldp enable
# Enable DLDP on fiber-optic port GigabitEthernet 1/0/49.
[Sysname] interface GigabitEthernet 1/0/49
[Sysname-GigabitEthernet1/0/49] dldp enable
dldp authentication-mode
Syntax
dldp authentication-mode { none | simple simple-password | md5 md5-password }
undo dldp authentication-mode
View
System view
Parameters
none: Sets the authentication mode on the port to none (Performs no authentication on the port).
simple: Sets the authentication mode on the port to plain text.
simple-password: Plain text authentication password, a string in plain text consisting of 1 to 16
characters.
md5: Sets the authentication mode on the port to MD5.
md5-password: MD5 authentication password, a string in plain text consisting of 1 to 16 characters or a
string in cipher text corresponding to the string in plain text.
Description
Use the dldp authentication-mode command to set the DLDP authentication mode and password on
the current port.
Use the undo dldp authentication-mode to remove the DLDP authentication mode and password on
the current port.
By default, the authentication mode on the current port is none.
Note that:
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