Hi,

i'm working several Hours on this Topic in the Past, because it's a Part of my Job. So i find out, that W32time is able to be a good to configure SNTPServer and a NTPClient and it can provide (S)NTP-Service (TCP-Port123) for other NTP-Clients such as Unix Boxes, Cisco Equipment. Also your primary windows domain controller(s) in your LAN can be synced via such konfigured W32time(Source). Member Computer in your Windows Domain(s) are automatically synced via the Domain Controller per default. Also an additional setting as Broadcast NTP Server is possible with W32time.
If you have a (cheap) DCF77 Receiver with any working Windows Driver, you can build your own "Stratum 1" ;-) Timesource with W32time on any Windows2K/XP Workstation in your LAN and you don't need Internet Access for syncing your Network time.
All you need to do is editing your Registry:
Start "regedit", and follow the Tree to:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time
Save/export this Key (w32time) for your Backup in a *.reg File.
You can find a detailed Description of the affected Registry Keys here:

http://www.microsoft.com/technet/prodtechnol/windowsserver2003/library/DepKit/60b22065-a3c9-42e2-8594-21d766e73339.mspx

Here comes my own config for W32time (WinXP-pro) to set up a DCF77 synced local NTP Server for my Network:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time]
"ErrorControl"=dword:00000001
"Group"=""
"Objectname"="LocalSystem"
"Start"=dword:00000002
"Type"=dword:00000020
"LocalNTP"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Config]
"LastClockRate"=dword:0002625a
"MinClockRate"=dword:000260d4
"MaxClockRate"=dword:000263e0
"FrequencyCorrectRate"=dword:00000004
"PollAdjustFactor"=dword:00000005
"LargePhaseOffset"=dword:00138800
"SpikeWatchPeriod"=dword:0000005a
"HoldPeriod"=dword:00000005
"MaxPollInterval"=dword:0000000f
"LocalClockDispersion"=dword:0000000a
"EventLogFlags"=dword:00000002
"PhaseCorrectRate"=dword:00000001
"MinPollInterval"=dword:0000000a
"UpdateInterval"=dword:00007530
"MaxNegPhaseCorrection"=dword:ffffffff
"MaxPosPhaseCorrection"=dword:ffffffff
"AnnounceFlags"=dword:00000005
"MaxAllowedPhaseOffset"=dword:0000012c

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters]
"ServiceMain"="SvchostEntry_W32Time"
"NtpServer"="127.127.1.0"
"Type"="NTP"
"LocalNTP"=dword:00000001
"Period"="SpecialSkew"
"Adj"=dword:0002626b
"msSkewPerDay"="-9200,0000"
"AviodTimeSyncOnWan"=dword:00000001
"ReliableTimeSource"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpClient]
"Enabled"=dword:00000001
"InputProvider"=dword:00000001
"AllowNonstandardModeCombinations"=dword:00000001
"CrossSiteSyncFlags"=dword:00000002
"ResolvePeerBackoffMinutes"=dword:0000000f
"ResolvePeerBackoffMaxTimes"=dword:00000007
"CompatibilityFlags"=dword:80000000
"EventLogFlags"=dword:00000000
"DllName"="C:\\WINDOWS\\System32\\w32time.dll"
"SpecialPollTimeRemaining"=hex(7):00,00
"SpecialPollInterval"=dword:00000e10

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpServer]
"Enabled"=dword:00000001
"InputProvider"=dword:00000000
"AllowNonstandardModeCombinations"=dword:00000001
"DllName"="C:\\WINDOWS\\System32\\w32time.dll"

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Enum]
"0"="Root\\LEGACY_W32TIME\\0000"
"Count"=dword:00000001
"NextInstance"=dword:00000001

If you query this Time source via "ntpq" (Unix) or net time... you will see this is a Stratum1 and your NTP-Clients will always prefer this as its Time Source, also if more than this NTP Server are configured in your NTP Client for redundancy.
The Diffrence between NTP and SNTP is a reduced command set in SNTP.

If you have additional Questions about this, email me.

mario_benndorf(at)hotmail.com