154 Options List
NTP Authentication
Authentication involves advanced configuration for NTP, and used to prevent tampering with the
timestamps on the logs generated by devices. You can configure a device to authenticate the time
sources to which the local clock is synchronized. When you enable NTP authentication, the device
synchronizes to a time source only if the source carries one of the authentication keys specified by
the ntp trusted-key command. The device drops any packets that fail the authentication check and
prevents them from updating the local clock. NTP authentication is disabled by default.
Option 34 Network Time Module
Status
Configure
NTP
PTP
SNMP
Clock
Network
System
Support
Logout
Authentication
Apply Reset
M
Enable Authentication
M
M
M
M
Key Table
ID Format Key Trusted
Figure C.29: NTP Authentication Page
There are four authentication formats (S, N, A, M) with different rules for each of the keys. For
example, a type M format (MD5) allows the key to have up to 31 ASCII characters like a password.
The key ID is an integer and identifies the NTP server key. If authentication is enabled, the client
will only synchronize with the server if it is trusted. Therefore, you must select the ”Trusted” check
box on the authentication page.