Lets say two parties (A and B) use kerberos v5 and they happened to have varied clocks which is more than 10 mins window time of Kerberos. How does Kerberos still enable them to arrive consensus at a time? What messages are exchanged for this re-synchronization?
1 Answer
Kerberos does not synchronize time between the KDC, Admin-server and clients. The administrators need to establish time-sync mechanisms such as NTP to ensure that system time between various entities involved in the Kerberos domain is kept synchronized.
Microsoft Windows domains specify a default tolerated time-offset of 5 minutes, although this setting can be changed by a Group security policy (GPO) configuration. A lower value is more secure than a higher value, but the trade-off is the risk of rejecting genuine remote clients which may have high time offsets.
See these references for more details: