IntermediateUnlock
Securing NTP with MD5 Authentication
Configure NTP MD5 authentication so a client (R2) synchronizes only to a trusted, authenticated master (R1). R1 is already an authoritative clock (ntp master 3). You will enable NTP authentication on both routers, define and trust key 1, and bind the key on R2's ntp server statement. Verification focuses on authenticated associations and status; actual time lock may take minutes and is not graded.