Sync the computer clocks for EthoVision XT and DSI Ponemah

Aim

To ensure high synchronicity between EthoVision XT data and physiological data collected with DSI Ponemah.

Background information

Synchronization between the EthoVision XT system and the DSI Ponemah system is based on a Network Time Protocol (NTP), a networking protocol for computer clock synchronization.

https://en.wikipedia.org/wiki/Network_Time_Protocol

The NTP Time Server runs on the DSI Ponemah computer and acts as time reference. The NTP Client runs on the EthoVision XT and adjusts that PC’s clock time based on the NTP Time Server.

Prerequisites

▪The NTP Server is already installed on the DSI Ponemah computer.

▪You need two installation files:

▪ntp-time-server-monitor-104.exe (NTP Server Monitor)

▪ntp-4.2.8p15-v2-win32-setup.exe (NTP Client).

Download the Time Server Monitor software from

https://www.meinbergglobal.com/english/sw/ntp-server-monitor.htm

Download the NTP Client for Windows from

https://www.meinbergglobal.com/english/sw/ntp.htm#ntp_stable

Procedure 1 - DSI Ponemah

1.On the DSI computer, create the following folder structure:

C:\NTP\

C:\NTP\ETC\

C:\NTP\Installation\

2.Copy the file ntp-time-server-monitor-104.exe to C:\NTP\Installation.

3.Double-click the file and follow the instructions.

As the Destination Folder, choose C:\NTP.

As the Select Program Manager Group, keep Meinberg selected.

Click Next> and continue installation.

4.When installation is done, a new icon NTP Time Server Monitor appears on the desktop.

5.Right-click on the icon and choose Run as administrator.

6.In the NTP Time Server Monitor window, click the NTP Status tab. You should see that a line highlighted in green. That indicates that the service is running correctly.

In the next steps you take note of the IP address of the DSI computer. Note that the DSI computer has two network cards; one is connected to the matrix (2.0) and the other one should be connected to the network which connects that computer to the EthoVision XT computer.

7.On the DSI computer, open the Network Connections.

8.Locate the item that corresponds to the network port to be connected to the EthoVision XT computer.

tip To find the correct port, temporarily disconnect the network cable from one of the network ports and check which item shows the message Network cable unplugged.

That helps you find which item corresponds to which network port.

9.Right-click the network adapter item and choose Status, then click Details.

10.Take note of the IP address next to IPv4 Address.

Procedure 2 - EthoVision XT

This procedure is meant to install the NTP Client on the computer which runs EthoVision XT. The NTP client adjusts the computer clock in such a way that it will be in sync with the clock of the NTP Server. This ensures that the system time of the EthoVision XT computer is in sync with the system time of the DSI computer.

1.On the EthoVision XT computer, create the following folder structure:

C:\NTP

C:\NTP\ETC

C:\NTP\ETC\ntp.conf

C:\NTP\Installation

C:\NTP\Installation\ntp-4.2.8p15-v2-win32-setup.exe

C:\NTP\Installation\ntp-time-server-monitor-104.exe

2.Double-click ntp-4.2.8p15-v2-win32-setup.exe.

3.Choose C:\NTP as the installation folder. Click Next and under Choose Components keep the default settings.

4.Under Files have been installed, keep C:\NTP\etc\ntp.conf selected file. This is the file that you copied in the first step, and contains all the necessary settings, except for the IP address of the DSI computer.

De-select Create an initial configuration file with the following settings.

5.Click Next and under Setting Up NTP Service, select Create and use a special NTP account (recommended). Leave all selections as they are.

6.Click Next and enter a name and password. Next, complete installation.

After this, the Service is installed and started automatically. If the service does not start after the installation, because you used an existing network account, do the following: (1) Start Services in Windows (see Administrative Tools in the Windows Control Panel). (2) Select the Network Time Protocol Daemon service. (3) Change the Logon properties to the desired account (when you do that, the account will be given services rights). (4) Start the Service.

7.On the EthoVision XT computer, double-click the file ntp-time-server-monitor-104.exe (for details see in Procedure 1 above).

8.When installation is done, run the NTP Time Server Monitor ad administrator and click the NTP Configuration file tab. There change the IP address by entering the one you found at the end of Procedure 1 (see also below).

Once ready, click the Save configuration button. At this point you will be asked to restart the service. tip You can always restart the service in the Windows Services.

9.Click the NTP Status tab you should see the green line indicating that the service is running correctly.

10.Click the Statistic tab in the NTP Time Server Monitor window. A few minutes later you can view the statistics of the NTP synchronization.

11.To monitor the offset between the server and the client, under Available Logfiles click the browse button and in the folder C:\NTP\ETC\ select the loop statistics file. Typically, one file is generated per day. Click that file in the list to view the time-offset plot (in red). In most cases the offset, that is the difference in the clock time between the computers, is within one millisecond.

The NTP.CONF file

The ntp.conf file is a text file which contains the lines as shown below. You can open the file with the Windows Notepad.

Make sure that the IP address shown in bold is the IP address of the NTP Time Server, that is, your DSI-computer.

# NTP Network Time Protocol

#IMPORTANT: WITH W7 MAKE SURE THE MONITOR RUNS AS ADMIN

# SET THIS IN THE PROPERTIES OF THE SHORTCUT

ignore_bigtimestep yes

# Use drift file

driftfile "C:\NTP\etc\ntp.drift"

# your local system clock, could be used as a backup

server 123.456.78.901 minpoll 4 maxpoll 4 burst iburst

# generate statistics

enable stats

statsdir "c:\NTP\etc"

statistics loopstats

# End of generated ntp.conf --- Please edit this to suite your needs

Notes

▪When the two computers are in the same network domain, the domain administrator can use his/her existing account. However it is always possible to create a separate account as described above. The account must have the rights to start the NTP Service.