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giving you strata 5, plus or minus 10 seconds. duh. may not be good enough.

First of all it's "stratum" not "strata".

Second, adding one layer between add's exactly one stratum, no less and no more.

Most public time sources (GPS/PPS/...) are between 1-3 and thus claim jumping to stratum 10 with single firewall, let's call it bollocks.

Here's a good short explanation how it works.

anyways these days one can build a strata-1 NTP server from GPS and run it on the internal network.

Building just one doesn't make sense if you take that option. Rule of thumb is that whenever you need local NTP servers, you also need to have 2-3 to provide you enough redundancy and make other important arrangements trying to make sure no single point failure would render them all unusable.

Playing* with GPS's devices isn't usually needed, unless you are in some special area of business which needs very accurate time (astronomy, telecoms, stocks-echange, ...).

Good working option is usually having 3 internal ntp servers, each syncing trough firewall (server mode) from internet national time base provider and perhaps or if not avail public ntp pool could work for many too. Then rest those three internal servers provide time for all other internal servers and workstations etc. and DHCP and other management solutions (satellite etc.) provision configuration for clients & servers company wide.

*) most who bring up that they have a GPS/PPS or the like time source have it for pure geek value, nothing more. I've had it too at home for a decade but retired it couple of years ago, on duty i've built and run time sources and ntp-services for decades (among many other things) for a very large university and couple of years nation wide telecoms for tens of millions people at time.

Ordinary office environments (AD, *nix file shares & kerberos) are happy anything with +/-5 sec, the router/firewall proposed above is good enough for that.

GPL requires for **non-commerical** unmodified redistribution (such as SimplyMEPIS download mirrors):
1) A copy of the GPL be provided (and for a distribution with glibc, a copy of the LGPL as well)
2) A list of the GPL/LGPL packages used and where the source code is available from (the source code can be provided by a previous location *IF* it is non-commerical redistribution)

GPL requires for commerical redistribution (such as can be ordered from the MEPIS store):
1) A copy of the GPL (and LGPL) be provided
2) A written offer for source code on a physical media (such as CD) that costs no more than recovering the costs of performing such redistribution (if time/materials to download and burn all the source packages is worth $50 then the cost is $50 even if the binary CD is only $15)

It seems silly for the FSF to go after MEPIS considering the on-going GPL violation that Google continues with for their Google Search Appliance at http://www.google.com/enterprise/gsa/

Google performs redistribution of a RedHat-like GNU/Linux distribution *WITHOUT* providing any written copy of the GPL or LGPL. There is no copy provided with the written documentation provided. And while there is a copyright/about option in the web administration piece of the appliance, it also fails to provide any copy of the GPL or LGPL. So far, I am not aware of any effort by the FSF to correct Google's actions and the group that provides support for the GSA has stated they have no intentions of changing their actions to comply with the GPL since they consider themselves to already be complying by *NOT* providing any copy of either license!

Also, EndRun Technologies has a small GNU/Linux distributions can be downloaded from:
http://www.endruntechnologies.com/download.htm

The source code is not available for download but is available on CD-ROM for a $100 fee.

Check out EndRun Techonologies. Stratum 1 time servers using either GPS or CDMA sources. Sorry, they don't have WWV ones.

Good Point. Another post provided a link to http://www.endruntechnologies.com they have a 1U rackmount system that gets it time from CDMA cellular network instead of GPA.

You have a better chance of getting CDMA signals in building than GPS. Plus, since you don't need the positioning aspects it seems like overkill to use GPS. ;-)

For a few of the european hosts, we use GPS time receivers, primarily the Motorolla Oncore UT+ kits. You can get eval units of these, google around. They're nearly as easy to use, but do require a kernel config change.

It's really kind of addictive playing with time. :-) And you get spoiled by never having any clock weirdness on any of your machines...

Try this one, it's pretty inexpensive. If you account for the time you'd spend DIY this might be the better option...

If you can get a digital signal on a CDMA-based cellphone from your basement, you might want to look into this horrifically-overpriced box.