Hi What's the topology of your network?
If you have asymmetric routing delays they can easily limit your accuracy. We apparently have some creative IT guys, so we even see non- stationary asymmetry on our LAN .... Bob Camp On Jun 20, 2007, at 9:05 PM, David Duchscher wrote: > On Jun 20, 2007, at 2:59 PM, Poul-Henning Kamp wrote: > >> In message <[EMAIL PROTECTED]>, >> David Duchscher >> writes: >> >>> I am looking at using a Soekris unit for NTP and was wondering if >>> people have a recommendation for which board to use? Traffic >>> will be >>> low, no encryption. I was looking at the 4801 as I see netgate.com >>> has a rack mount case for it but that is just a nicety and not >>> requiredment. GPS clock we are looking at using is the GPS 17HVS. >>> Any comments, suggestions, pointers, etc would be greatly >>> appreciated. >> >> Go for the 4501, you can get much better precision if you throw >> a GPS and possibly a good X-tal after it. >> >> John wrote up my design here: >> >> http://www.febo.com/pages/soekris/ > > That really is sweet. > > A couple of questions, if you have the time. The accuracy requirement > for our setup is +/- 1 millisecond, do you think the 4501 plus the > Garmin GPS unit with the standard clock crystal would be able to > meet that requirement? The Garmin GPS 17HVS PPS line has a > specification of +/- 1 microsecond. Secondly, do you have an idea > of what the accuracy of the such a setup would be? It would be fun > to build a very accurate NTP server but the requirements are not > there. I am trying to keep things as simple and reliable as possible > since I am not the only admin that will be maintaining the unit. > At the same time, I rather not spend 400 for a Symmetricom NTS-150. > As an example of our thinking, we decided on the Garmin GPS sensor > for easy installation and it being designed for marine applications, > would be able to handle the hot, long days of sun, and wet environment > we have here. > > The Garmin manual is located here: > > http://www8.garmin.com/manuals/GPS16HVS_TechnicalSpecifications.pdf > > Thanks for your time, > -- > DaveD > > _______________________________________________ > Soekris-tech mailing list > [email protected] > http://lists.soekris.com/mailman/listinfo/soekris-tech > _______________________________________________ Soekris-tech mailing list [email protected] http://lists.soekris.com/mailman/listinfo/soekris-tech
