26 25-Seven Program Delay Manager
Version 2.3 Manual April 2013
Gateway
The IP address of your LAN’s Gateway system or
router that connects PDM to the Internet, also supplied by your ISP or
IT department. It’s needed so the PD-Alert system can send its e-mail
to servers outside your local area network.
NTP
Enables or disables PDM’s ability to update its time-
of-day clock automatically from a Network Time Protocol server
1
(see
box, next page). If enabled, PDM’s clock cannot be manually set.
NTP Server
Enter the IP address of the network time server. This
menu item appears only if NTP is enabled.
Network troubleshooting
PDM’s Internet services (such as PD-Alert e-mails, Network Time Protocol, and Web
remote control) require proper Internet Protocol addressing. In many installations this
is provided automatically by your station’s data router, when you choose DHCP (page
25). However, some data networks don’t support DHCP, or require fixed IP addresses. If
that is the case, you will have to manually enter the IP Address, Subnet Mask, Gateway,
and DNS numbers.
Network Time Protocol servers supply accurate time-of-day and other data over the
Internet. PDM can use them to automatically set its internal clock. Your facility might
also have its own NTP server.
NTP servers are often identified by a domain name—a familiar-sounding “.com” or
“.gov” URL— rather than their numeric IP address. PDM requires numeric IP ad-
dresses.
You’ll find a list of US servers, with both their domain names and their IP addresses,
at the National Institute of Standards and Technology’s website
2
. International time
server domain names are listed at www.ntp.org. Please respect the access policies
listed by the server provider and IT department. PDM users should never select a Pri-
mary server for NTP updating; use Pool or Secondary servers instead.
The best way we have found to test whether NTP services are working is to manually
offset your PDM clock by a couple of minutes, then enable NTP. If your network con-
nections are working and your NTP address is valid, the system clock should quickly
acquire the correct time.
1
NTP works fastest if the system clock is already fairly close to the current time. We recommend you set
the
Time/Date
and
Time
Zone
manually (page 24) before enabling this feature.
2
The list itself is currently at http://tf.nist.gov/tf-cgi/servers.cgi. If NIST has moved it from that location,
use the search box on their home page, www.nist.gov, to find “Internet Time Service”.
About NTP
Summary of Contents for program delay manager
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