Re: follow up on Windows 2003 SP1 Time Service versus ntpd - NTP

This is a discussion on Re: follow up on Windows 2003 SP1 Time Service versus ntpd - NTP ; I've been trying to get Windows XP SP2 to work as an NTP client for a couple weeks now, but with very, very poor results compared to the results I can obtain with Windows port of NTP. As best I ...

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Thread: Re: follow up on Windows 2003 SP1 Time Service versus ntpd

  1. Re: follow up on Windows 2003 SP1 Time Service versus ntpd

    I've been trying to get Windows XP SP2 to work as an NTP client for a
    couple weeks now, but with very, very poor results compared to the
    results I can obtain with Windows port of NTP.

    As best I understand it, Windows XP has the same Windows Time Service as
    Windows 2003 ... at least based on the common registry parameters.

    Is there any reason I shouldn't be able to get my XP time service to
    sync the time as well as NTP ... as you have demonstrated with Win2003?

  2. Re: follow up on Windows 2003 SP1 Time Service versus ntpd

    Based on my previous experiences with Windows 2000 SP4 and Windows XP
    SP2 with NTP and WTS, I can assure you the performance you've obtained
    is the best you can hope.

    With Win2k synced on a RS232 GPS I had an offset of + / - 5 ... 10 ms
    (far away from a FreeBSD system).

    Please note that on a heavy loaded system (Windows / Linux / any
    operating system) the performances degades rapidly (in the order of
    hundreds of milliseconds or in some cases more). We have in our NOC a
    server with 2 Xeon / 1.4 GHz / 4 GB RAM / 1,5TB HDD -with Linux - a
    heavy loaded machine. The offset is sometimes more than 400-500ms !
    When there is a very low user activity the offset is 1-2 ms, synced
    with an internal Stratum 1 server on a gigabit network.

    For information regarding time keeping and interrupts on Windows
    systems may I recommend these:

    http://www.amazon.com/gp/product/073...913736?ie=UTF8

    and

    http://www.amazon.com/gp/product/084...913736?ie=UTF8


  3. Re: follow up on Windows 2003 SP1 Time Service versus ntpd

    HokeyPokey wrote:
    > I've been trying to get Windows XP SP2 to work as an NTP client for a
    > couple weeks now, but with very, very poor results compared to the
    > results I can obtain with Windows port of NTP.
    >
    > As best I understand it, Windows XP has the same Windows Time Service as
    > Windows 2003 ... at least based on the common registry parameters.
    >
    > Is there any reason I shouldn't be able to get my XP time service to
    > sync the time as well as NTP ... as you have demonstrated with Win2003?


    W32TIME is NOT NTP. It is Microsoft's feeble attempt at implementing
    SNTP. Only random chance will make it work as well as SNTP. Microsoft
    implementd W32TIME because they needed to keep systems within a couple
    of minutets of each other in order for Kerberos authentication to work
    properly. Kerberos is happy if the time is within two minutes (or
    something like that, I'm too lazy to look it up). W32TIME does better
    than that, maybe within 100 milliseconds.

    If you want tight synchronization and accurate time, forget W32TIME!!

  4. Re: follow up on Windows 2003 SP1 Time Serviceversus ntpd

    Richard B. Gilbert wrote:
    > Kerberos is happy if the time is within two minutes (or
    > something like that, I'm too lazy to look it up).


    5 minutes.

    Danny
    _______________________________________________
    questions mailing list
    questions@lists.ntp.isc.org
    https://lists.ntp.isc.org/mailman/listinfo/questions


  5. Re: follow up on Windows 2003 SP1 Time Service versus ntpd

    Richard B. Gilbert wrote:
    > W32TIME is NOT NTP. It is Microsoft's feeble attempt at implementing
    > SNTP. Only random chance will make it work as well as SNTP.


    W32time as included in Windows Server 2003 with SP1 and higher is,
    according to Microsoft, an NTPv3 compliant server and client (not just
    SNTP). It seems to perform well within the limits of its claimed
    accuracy (2^-6), is more configurable than predecessors, and seems to
    send compliant packets with correct stratum, precision, etc.

    All earlier versions of w32time (including all versions of XP and 2000)
    are indeed problematic and SNTP-like in their behavior. But your
    blanket statement of "W32time always sucks" needs some updating.

    So, is Win2003-SP1's time service as accurate as ntpd? Of course not.
    But it is not just a feeble attempt at SNTP, and it does work fairly
    well as an NTP server and client in my testing.


  6. Re: follow up on Windows 2003 SP1 Time Service versus ntpd

    Ry,

    Ry wrote:
    > W32time as included in Windows Server 2003 with SP1 and higher is,
    > according to Microsoft, an NTPv3 compliant server and client (not just
    > SNTP). It seems to perform well within the limits of its claimed
    > accuracy (2^-6), is more configurable than predecessors, and seems to
    > send compliant packets with correct stratum, precision, etc.
    >
    > All earlier versions of w32time (including all versions of XP and 2000)
    > are indeed problematic and SNTP-like in their behavior.

    [...]

    Can you tell us a specific version number of w32time which implements this?

    It would make it easier to tell whether the "good new" version or the "bad
    old" version of w32time is running. I could imagine the new version might
    also become available for XP or so in a service pack.

    Martin
    --
    Martin Burnicki

    Meinberg Funkuhren
    Bad Pyrmont
    Germany

  7. Re: follow up on Windows 2003 SP1 Time Service versus ntpd

    Martin Burnicki wrote:
    > Can you tell us a specific version number of w32time which implements this?
    >
    > It would make it easier to tell whether the "good new" version or the "bad
    > old" version of w32time is running. I could imagine the new version might
    > also become available for XP or so in a service pack.
    >


    The machine I tested - which gave the decent results I posted here
    previously - is Win 2003 SP1 plus all security hotfixes. However, since
    there have been no pathces for w32time, I believe these files are the
    same as the versions that came with Service Pack 1 for Windows 2003
    Server.

    w32time.dll v5.2.3790.1830
    w32tm.exe v5.2.3790.1830


  8. Re: follow up on Windows 2003 SP1 Time Service versus ntpd

    Ry wrote:
    > The machine I tested - which gave the decent results I posted here
    > previously - is Win 2003 SP1 plus all security hotfixes. However, since
    > there have been no pathces for w32time, I believe these files are the
    > same as the versions that came with Service Pack 1 for Windows 2003
    > Server.
    >
    > w32time.dll v5.2.3790.1830
    > w32tm.exe v5.2.3790.1830


    Thanks.

    Martin
    --
    Martin Burnicki

    Meinberg Funkuhren
    Bad Pyrmont
    Germany

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