Time synchronisation in modern internet networks is necessary, all computers need to get the time as many applications, from sending an email to storing information are reliant on the personal computer knowing when the event happened.

From Microsoft Windows Server 2000 onwards has a time synchronisation utility built into the operating system called  Windows Time Service which can be configured to operate as a NTP server.Windows Server 2008 can easily settle the system clock to use UTC (Coordinated Universal Time) by accessing an Internet source.

To accomplish this, the user just has to double click the clock on the desktop and adjust the settings in the Internet Time tab.It must be noticed all the same, that Microsoft and other operating system manufacturers strongly advise that external timing references should be used as Internet sources can not be authenticated.

To configure the Windows Time service to use an external time source, please click start, Run and type regedit then click OK.

Find the following subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters\Type
In the right pane, right-click Type and Modify, type NTP in the Value data box then click OK.

Find this subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Config\AnnounceFlags.
In the right pane, right-click AnnounceFlags and click Modify. The "AnnounceFlags" registry entry indicates whether the server is a trusted time reference, 5 shows a trusted source so type 5  in the Edit DWORD Value box, then click OK.

NTP is an Internet protocol used for the transfer of accurate time, providing time information along so that a precise time can be obtained.To enable the Network Time Protocol , find NTP server

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpServer\
In the right pane, right-click Enabled, then click Modify.

In the Edit DWord Value box, type 1 under Value data, then click OK.Now go back and click on
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters\NtpServer
In the right pane, right-click NtpServer, then Modify, in the Edit DWORD Value under Value Data type In the right pane, right-click NtpServer, then Modify, in the Edit DWORD Value under Value Data type the Domain Name System (DNS), each DNS must be unique and you must append 0x1 to the end of each DNS name otherwise changes will not take effect.

Find and click the following
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpClient\SpecialPollInterval
In the right pane, right-click SpecialPollInterval, then click Modify.In the Edit DWORD Value box, under Value Data, type the number of seconds you want for each poll, ie 900 will poll every 15 minutes, then click OK.
To configure the time correction settings,find
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\config
In the right pane, right-click MaxPosPhaseCorrection, then Modify, in the Edit DWORD Value box, under Base, click Decimal, under Value Data, type a time in seconds such as 3600 (an hour) then click OK.
Now go back and click:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\config
In the right pane, right-click MaxNegPhaseCorrection, then Modify.

In the Edit DWORD box under base, click Decimal, under value data type the time in seconds you want to poll such as 3600,Exit Registry Editor.Now, to restart windows time service, click Start, Run and type:

net stop w32time
net start w32time

And now your time server should be running.



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