25-24 
z  Switch C works in the broadcast server mode and sends out broadcast messages from 
VLAN-interface 2. 
z  Switch D works in the broadcast client mode and receives broadcast messages through 
VLAN-interface 2. 
z  NTP authentication is enabled on both Switch C and Switch D. 
Figure 25-12 Network diagram for configuration of NTP broadcast mode with authentication 
 
 
Configuration procedure 
1)  Configuration on Switch C: 
# Configure NTP authentication. 
<SwitchC> system-view 
[SwitchC] ntp-service authentication enable 
[SwitchC] ntp-service authentication-keyid 88 authentication-mode md5 123456 
[SwitchC] ntp-service reliable authentication-keyid 88 
# Specify Switch C as an NTP broadcast server, and specify an authentication key.   
[SwitchC] interface vlan-interface 2 
[SwitchC-Vlan-interface2] ntp-service broadcast-server authentication-keyid 88 
2)  Configuration on Switch D: 
# Configure NTP authentication. 
<SwitchD> system-view 
[SwitchD] ntp-service authentication enable 
[SwitchD] ntp-service authentication-keyid 88 authentication-mode md5 123456 
[SwitchD] ntp-service reliable authentication-keyid 88 
# Configure Switch D to work in the NTP broadcast client mode.   
[SwitchD] interface vlan-interface 2 
[SwitchD-Vlan-interface2] ntp-service broadcast-client 
Now, Switch D can receive broadcast messages through VLAN-interface 2, and Switch C can send 
broadcast messages through VLAN-interface 2. Upon receiving a broadcast message from Switch C, 
Switch D synchronizes its clock to that of Switch C.   
# View the NTP status of Switch D after clock synchronization.   
[SwitchD-Vlan-interface2] display ntp-service status