> > 4) If you are running NTP [1] the all bets are off. It could easily set > the time backwards. >
NTP will normally only set time backwards when it first starts. After that, it should never change time backwards. Since a typical mail server runs 24 hours a day, that should effectively mean time is monotonically increasing unless the host operating system messes with it. > David > > [1] NTP can only possibly 'synchronise' clocks to within the time taken > for a message to travel from one system to the other. NTP can and does set time more accurately than the propagation time between nodes. What is more important is the variation in propagation time, and NTP attempts to average that out, also. > Given the transit time for messages isn't constant (except on > trivial networks) IMHO trying to get sub-second synchronisation > is rather pointless, better is to write protocols that don't > rely on a 'universal' time frame. NTP easily obtains sub-second accuracy unless the hardware clock is exceedingly crummy. You should be able to count on it to be within 0.1 second even under poor conditions. But I agree that the protocol shouldn't depend on that. > > -- > David Laight: [EMAIL PROTECTED] - Bob ------------------------------------------------------- This SF.NET email is sponsored by: Thawte.com Understand how to protect your customers personal information by implementing SSL on your Apache Web Server. Click here to get our FREE Thawte Apache Guide: http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0029en _______________________________________________ courier-users mailing list [EMAIL PROTECTED] Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
