On Mon, June 15, 2015 8:01 pm, Bob Camp wrote: > Unless you have fancy switches on your LAN (1588 stamping), PTP > performance will be dependent on load and the "goodness" of the switches you do > have. These are pretty much the same (external) things that impact NTP.
Yes, but proper differentiated services setup with multiple queues can help mitigate that to a large extent. I'm still trying to get my PTP setup going, so I don't have any measurements of my own yet, but there are lots of examples of large commercial systems in use without transparent clock support which can maintain sub-microsecond synchronization. Using PTP transparent switches should get down into the couple hundred nanosecond range or better, but even without 800 or so nanoseconds has been shown to be consistently possible. I have no idea what level of synchronization you could keep using just NTP with diffserv. That might be an interesting experiment to try for those who only want NTP and aren't interested in setting up PTP. -- Chris Caudle _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
