+* Make all of the html/ .html files use the same format for "Last update".
(4.2.7p451) 2014/07/17 Released by Harlan Stenn <stenn@ntp.org>
* Fix the "Last update" entries in the html/ subtree.
(4.2.7p450) 2014/07/16 Released by Harlan Stenn <stenn@ntp.org>
<h3>Association Management</h3>
<img src="pic/alice51.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>Alice's Adventures in Wonderland</i>, Lewis Carroll</a>
<p>Make sure who your friends are.</p>
-<p>
- <EM>Modified: 31-Jan-2014</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->31-Jan-2014 06:54<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/hand.txt"></script>
<h3>Command Index</h3>
<img src="pic/alice38.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html">from <i>Alice's Adventures in Wonderland</i>, Lewis Carrol</a>
<p>The Mad Hatter says "Bring it on".</p>
-<p>
-<EM>Modified: 31-Jan-2014</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->31-Jan-2014 06:54<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/accopt.txt"></script>
<h3>Build Options</h3>
<img src="pic/pogo3a.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>Pogo</i>, Walt Kelly</a>
<p>Gnu autoconfigure tools are in the backpack.</p>
- <p>Last update: <csobj format="ShortTime" h="25" locale="00000409" region="0" t="DateTime" w="61">Monday,
- December 15, 2008 20:54</csobj> UTC<csobj format="LongDate" h="25" locale="00000409" region="0" t="DateTime" w="250"></csobj></p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 04:59<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<hr>
<p>Most modern software distributions include an autoconfigure utility which
<img src="pic/boom3a.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>Pogo</i>,
Walt Kelly</a>
<p>The chicken is getting configuration advice.</p>
-<p>
- <EM>Modified: 11-Oct-2010</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:01<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/command.txt"></script>
<body>
<h3>Copyright Notice</h3>
<img src="pic/sheepb.jpg" alt="jpg" align="left"> "Clone me," says Dolly sheepishly.
-<p>
-<EM>Modified: 10-Mar-2014</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 04:46<!-- #EndDate -->
+ UTC</p>
<br clear="left">
</p>
<hr>
<h3>Event Messages and Status Words</h3>
<img src="pic/alice47.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html">from <i>Alice's Adventures in Wonderland</i>, Lewis Carroll</a>
<p>Caterpillar knows all the error codes, which is more than most of us do.</p>
-<p>
- <EM>Modified: 31-Jan-2014</EM>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->16-Jul-2014 04:48<!-- #EndDate -->
+ UTC</p>
</p>
<br clear="left">
<h4>Related Links</h4>
</head>
<body>
<h3>Clock Discipline Algorithm</h3>
-<p>
- <EM>Modified: 15-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:03<!-- #EndDate -->
+ UTC</p>
<h4>Table of Contents</h4>
<ul>
<li class="inline"><a href="#intro">General Overview</a></li>
<h3>Automatic Server Discovery Schemes</h3>
<img src="pic/alice51.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html">from <i>Alice's Adventures in Wonderland</i>, Lewis Carroll</a>
<p>Make sure who your friends are.</p>
-<p>
- <EM>Modified: 31-Oct-2011</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:04<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/hand.txt"></script>
<body>
<h3>bc635VME/bc350VXI Time and Frequency Processor</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p>Address: 127.127.16.<i>u</i><br>
<body>
<h3>Generic NMEA GPS Receiver</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->31-Mar-2014 03:55<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p><a href="../refclock.html">Reference Clock Drivers</a></p>
<hr>
<script type="text/javascript" language="javascript" src="scripts/footer.txt"></script>
-
-
- <EM>Modified: 31-Mar-2014</EM>
</body></html>
<body>
<h3>Hewlett Packard 58503A GPS Receiver and HP Z3801A</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->5-Oct-2005 04:37<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p>Address: 127.127.26.<i>u</i><br>
<body>
<h3>Arcron MSF Receiver</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p>Address: 127.127.27.<i>u</i><br>
<body>
<h3>Shared Memory Driver</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->14-Sep-2012 18:48<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p>Address: 127.127.28.<i>u</i><br>
<body bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">
<h1><font size="+2">Trimble Palisade and Thunderbolt Receivers</font>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
</h1>
<table>
<body>
<h3>Motorola Oncore GPS receiver</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p>Address: 127.127.30.<i>u</i><br>
<body>
<h3>Rockwell Jupiter GPS receiver</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p>Address: 127.127.31.<i>u</i><br>
<body>
<h3>Chrono-log K-series WWVB receiver</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p>Address: 127.127.32.<i>u</i><br>
Z - timestamp indicator
hh:mm:ss - local time
</pre>
- <!-- hhmts start -->Last modified: Sun Feb 14 11:57:27 EST 1999 <!-- hhmts end -->
<hr>
<script type="text/javascript" language="javascript" src="scripts/footer.txt"></script>
</body>
<body>
<h3>Dumb Clock</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p>Address: 127.127.33.<i>u</i><br>
C - \r (carriage return)
L - \n (newline)
</pre>
- <hr>
- <!-- hhmts start -->Last modified: Sun Feb 14 12:07:01 EST 1999 <!-- hhmts end -->
<hr>
<script type="text/javascript" language="javascript" src="scripts/footer.txt"></script>
</body>
<body>
<h3>Ultralink Clock</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->31-Dec-2007 19:43<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p>Address: 127.127.34.<i>u</i><br>
<body>
<h3>Conrad parallel port radio clock</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p>Address: 127.127.35.<i>u</i><br>
<body>
<h3>Forum Graphic GPS Dating station</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p>Address: 127.127.37.<i>u</i><br>
<body bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">
<h1><font face="Arial"><i><blink><font size="5">hopf</font></blink></i><font size="+2"> </font><font size="3">Serial Line Receivers (6021 and kompatible)</font></font></h1>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h2><font size="+1">Synopsis</font></h2>
<table width="100%">
<hr>
<h3>Questions or Comments:</h3>
<p><a href="mailto:altmeier@atlsoft.de">Bernd Altmeier</a><a href="http://www.ATLSoft.de"><br>Ing.-Büro für Software www.ATLSoft.de</a></p>
- <p>(last updated 02/28/2001)<br> </p>
<hr>
<script type="text/javascript" language="javascript" src="scripts/footer.txt"></script>
</body>
<body bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">
<h1><font face="Arial"><i><blink><font size="5">hopf</font></blink></i><font size="+2"> </font><font size="3">PCI-Bus Receiver (6039 GPS/DCF77)</font></font></h1>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<div align="center">
<center>
<hr>
<h3>Questions or Comments:</h3>
<p><a href="mailto:altmeier@atlsoft.de">Bernd Altmeier</a><a href="http://www.ATLSoft.de"><br>Ing.-Büro für Software www.ATLSoft.de</a></p>
- <p>(last updated 03/02/2001)<br> </p>
<hr>
<script type="text/javascript" language="javascript" src="scripts/footer.txt"></script>
</body>
<body>
<h3>JJY Receivers</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->3-May-2011 00:20<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
Address: 127.127.40.<em>u</em><br>
<body>
<h3>Zyfer GPStarplus Receiver</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
Address: 127.127.42.<i>u</i><br>
<body>
<h3>RIPE NCC interface for Trimble Palisade</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<img src="../pic/driver43_2.jpg" alt="Trimble Acutime 2000" align="right">
<h4>Synopsis</h4>
<body>
<h1>NeoClock4X - DCF77 / TDF serial line receiver<br>
</h1>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr size="2" width="100%">
<h2>Synopsis</h2>
<table width="100%">
<body>
<h3>Spectracom TSYNC PCI</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->26-Mar-2012 05:10<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
Address: 127.127.45.<i>u</i><br>
<body>
<h3>GPSD NG client driver</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->1-Mar-2014 03:48<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<body>
<h3>IRIG Audio Decoder</h3>
<p>Author: David L. Mills (mills@udel.edu)<br>
- lart upsdate:
- <!-- #BeginDate format:En2m -->15-Nov-2012 06:43<!-- #EndDate -->
+Last update:
+ <!-- #BeginDate format:En2m -->17-Jul-2014 02:17<!-- #EndDate -->
UTC</p>
<hr>
<h4>Synopsis</h4>
<body>
<h3>Radio CHU Audio Demodulator/Decoder</h3>
<p>Author: David L. Mills (mills@udel.edu)<br>
- <!-- #BeginDate format:En2m -->15-Nov-2012 06:43<!-- #EndDate -->
+Last update:
+ <!-- #BeginDate format:En2m -->17-Jul-2014 02:17<!-- #EndDate -->
UTC</p>
<hr>
<h4>Synopsis</h4>
<body>
<h3>Generic Reference Driver</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->27-Jan-2014 05:31<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
Address: 127.127.8.<em>u</em><br>
<body>
<h3>Magnavox MX4200 GPS Receiver</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
Address: 127.127.9.<i>u</i><br>
<body>
<h1>MX4200 Receiver Data Format</h1>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h2>Table of Contents</h2>
<ul>
<body>
<h3>Motorola ONCORE - The Shared Memory Interface</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Introduction</h4>
<p>In NMEA mode, the Oncore GPS receiver provides the user with the same information as other GPS receivers. In BINARY mode, it can provide a lot of additional information.</p>
<body>
<h3>European Automated Computer Time Services</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<p>Several European countries use the following message data format:</p>
<p><font size="-1" face="Courier New">Data format<br>
</head>
<body>
<h3>External Clock Discipline and the Local Clock Driver</h3>
-<p>
- <EM>Modified: 11-Sep-2011</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->9-May-2014 04:46<!-- #EndDate -->
+ UTC</p>
<hr>
<p>The NTPv4 implementation includes provisions for an external clock, where
the system clock is implemented by some external hardware device.
</head>
<body>
<h3>Clock Filter Algorithm</h3>
-<p>
- <EM>Modified: 15-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:05<!-- #EndDate -->
+ UTC</p>
<hr>
<p>The clock filter algorithm processes the offset and delay samples produced by the on-wire protocol for each peer process separately. It uses a sliding window of eight samples and picks out the sample with the least expected error. This page describes the algorithm design principles along with an example of typical performance.</p>
<div align="center"><img src="pic/flt5.gif" alt="gif">
<h3>Hints and Kinks</h3>
<img src="pic/alice35.gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html"> from <i>Alice's Adventures in Wonderland</i>, Lewis Carroll</a>
<p>Mother in law has all the answers.</p>
-<p>
- <EM>Modified: 11-Sep-2011</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:06<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<hr>
<p>This is an index for a set of troubleshooting notes contained in individual text files in the <tt>./hints</tt> directory. They were supplied by various volunteers in the form of mail messages, patches or just plain word of mouth. Each note applies to a specific computer and operating system and gives information found useful in setting up the NTP distribution or site configuration. The notes are very informal and subject to errors; no attempt has been made to verify the accuracy of the information contained in them.</p>
<body>
<h3>SCO Unix hints</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<h4>Older SCO Unix versions</h4>
<p>NTP 4.0.x does not run on SCO Unix prior to version 3.2.5.0.0. If you need NTP on an older SCO Unix system and don't mind to modify your kernel, use 3.5.91 which has patches for SCO Unix 3.2.4.x. Apply the kernel modifications as described in <a href="http://www.echelon.nl/en/ntp/sco3-recipe.html">XNTP on SCO 3.2.4.2</a>.</p>
<h4>Compiling NTP</h4>
<BODY>
Information on compiling and executing ntpd under Solaris.
<BR>
-Last Updated: Sun Jun 21 01:32:18 EDT 1998,
+<p>Last update:
+ <!-- #BeginDate format:En2m -->27-Jan-2014 05:31<!-- #EndDate -->
+ UTC,
John Hawkinson,
<! -- This is deliberately not a mailto -- > <jhawk@MIT.EDU>
+</p>
<P>
If you're not running Solaris 2.5.1 or later, it is likely
that you will have problems; upgrading would be a really good plan.
<body link="#00008B" vlink="#8B0000">
<h4>VxWorks port of NTP</h4>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<p>Creating a port for vxWorks posed some problems. This port may help as a starting point for similar ports to real-time OS's and other embeddable kernels, particularly where <tt>main()</tt> is not allowed, and where the configure scripts need to be altered.</p>
<h4>Configuration issues</h4>
<p>I decided to do as little invasive surgery as possible on the NTP code, so I brought the vxWorks header tree in line with the standard Unix tree. The following changes were needed, as a side effect these changes will allow for easy porting of other autoconfigure enabled code.</p>
</head>
<body>
<h3>Historical Notes</h3>
-<p>
- <EM>Modified: 03-Oct-2011</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:07<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Historical Notes on NTP Upgrades</h4>
<p>This is an interim report on recent upgrades to the NTPv4 reference implementation code base and documentation. This report documents the upgrade program, which began in June 2007 and continued until March 2008. It is very important to recognize that this historic document describes the upgrade status as of 2008. Additional upgrades have been implemented since then. As of mid 2011, the additional upgrades are documented on the <a href="release.html">NTP Version 4 Release Notes</a> page.</p>
<h3>How to Write a Reference Clock Driver</h3>
<img src="pic/pogo4.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html">from <i>Pogo</i>, Walt Kelly</a>
<p>You need a little magic.</p>
-<p>
- <EM>Modified: 11-Sep-2010</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:08<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/misc.txt"></script>
</head>
<body>
<h3>The Huff-n'-Puff Filter</h3>
-<p>
- <EM>Modified: 15-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:09<!-- #EndDate -->
+ UTC</p>
<hr>
<p>In scenarios where a considerable amount of data are downloaded or uploaded using DSL or telephone modem lines, timekeeping quality can be seriously degraded. This occurs because the traffic volume, and thus the queuing delays, on the upload and download directions of transmission can be very different. In many cases the apparent time errors are so large as to exceed the step threshold and a step correction can occur during and after the data transfer.</p>
<p>The huff-n'-puff filter is designed to correct the apparent time offset in these cases. It depends on knowledge of the propagation delay when no other traffic is present, such as during other than work hours. The filter remembers the minimum delay over the most recent interval measured usually in hours. Under conditions of large delay, the filter corrects the apparent offset using the sign of the offset and the difference between the apparent delay and minimum delay. The name of the filter reflects the negative (huff) and positive (puff) correction, which depends on the sign of the offset. The filter is activated by the <tt>tinker huffpuff</tt> command, as described in the <a href="miscopt.html">Miscellaneous Options</a> page.</p>
<h3>Kernel Model for Precision Timekeeping</h3>
<p><img src="pic/alice61.gif" alt="gif" align="left"> <a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>Pogo</i>, Walt Kelly</a></p>
<p>Alice finds the kernel a house of cards.</p>
-<p>
- <EM>Modified: 15-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:10<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/misc.txt"></script>
<body>
<h3>PPSAPI Interface for Precision Time Signals</h3>
<img src="pic/tonea.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html">from <i>NBS Special Publication 432, 1979</i></a> (out of print)
-<p>
- <EM>Modified: 11-Sep-2010</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:10<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<p>
<h3><tt>ntp-keygen</tt> - generate public and private keys</h3>
<p><img src="pic/alice23.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html">from <i>Alice's Adventures in Wonderland</i>, Lewis Carroll</a></p>
<p>Alice holds the key.</p>
-<p>
- <EM>Modified: 29-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:11<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/manual.txt"></script>
</head>
<body>
<h3>Leap Second Processing</h3>
-<p>
- <EM>Modified: 30-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:11<!-- #EndDate -->
+ UTC</p>
<hr>
<p>About every eighteen months the International Earth Rotation Service (IERS) issues a bulletin announcing the insertion of a leap second in the Universal Coordinated Time (UTC) timescale. Ordinarily, this happens at the end of the last day of June or December; but, in principle, it could happen at the end of any month. While these bulletins are available on the Internet at <a href="http://www.iers.org">www.iers.org</a>, advance notice of leap seconds is also available in signals broadcast from national time and frequency stations, in GPS signals and in telephone modem services. Many, but not all, reference clocks recognize these signals and many, but not all, drivers for them can decode the signals and set the leap bits in the timecode accordingly. This means that many, but not all, primary servers can pass on these bits in the NTP packet heard to dependent secondary servers and clients. Secondary servers can pass these bits to their dependents and so on throughout the NTP subnet.</p>
<p> A leap second is inserted following second 59 of the last minute of the day and becomes second 60 of that day. A leap second is deleted by omitting second 59 of the last minute of the day, although this has never happened and is highly unlikely to happen in future. So far as is known, there are no provisions in the Unix or Windows libraries to account for this occasion other than to affect the conversion of an NTP datestamp or timestamp to conventional civil time.</p>
<h3>Miscellaneous Commands and Options</h3>
<img src="pic/boom3.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>Pogo</i>, Walt Kelly</a>
<p>We have three, now looking for more.</p>
-<p>
- <EM>Modified: 31-Jan-2014</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->31-Jan-2014 06:54<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/command.txt"></script>
<h3>Monitoring Commands and Options</h3>
<img src="pic/pogo8.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html"></a> from <i>Pogo</i>, Walt Kelly</a>
<p>Pig was hired to watch the logs.</p>
-<p>
- <EM>Modified: 31-Jan-2014</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->31-Jan-2014 06:54<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/command.txt"></script>
<h3><tt>ntpd</tt> System Log Messages</h3>
<img src="pic/flatheads.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>Alice's Adventures in Wonderland</i>, Lewis Carroll</a>
<p>The log can be shrill at times.</p>
-<p>
- <EM>Modified: 11-Sep-2010</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:12<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<p>
</head>
<body>
<h3><tt>ntp-wait</tt> - waits until ntpd is in synchronized state</h3>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->12-Jul-2011 22:03<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<p><tt>ntp-wait [ -v ] [ -n <i>tries</i> ] [ -s <i>seconds</i> ]</tt></p>
<h3><tt>ntpd</tt> - Network Time Protocol (NTP) Daemon</h3>
<img src="pic/wingdorothy.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>The Wizard of Oz</i>, L. Frank Baum</a>
<p>You need help from the monkeys.</p>
-<p>
- <EM>Modified: 10-Feb-2014</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:14<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/command.txt"></script>
<h3><tt>ntpdate</tt> - set the date and time via NTP</h3>
<img src="pic/rabbit.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>Alice's Adventures in Wonderland</i>, Lewis Carroll</a>
<p>I told you it was eyeball and wristwatch.</p>
-<p>
- <EM>Modified: 31-Jan-2014</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->9-Feb-2014 03:34<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<hr>
<p>Disclaimer: This program has known bugs and deficiencies and nobody
<h3><tt>ntpdc</tt> - special NTP query program</h3>
<img src="pic/alice31.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>Alice's Adventures in Wonderland</i>, Lewis Carroll</a>
<p>This program is a big, deprecated puppy.</p>
-<p>
-<EM>Modified: 31-Jan-2014</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->31-Jan-2014 06:54<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>More Help</h4>
<script type="text/javascript" language="javascript" src="scripts/manual.txt"></script>
<h3><tt>ntpdsim</tt> - Network Time Protocol (NTP) Simulator</h3>
<img src="pic/oz2.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html">from <i>The Wizard of Oz</i>, L. Frank Baum</a>
<p>All in a row.</p>
-<p>
- <EM>Modified: 31-Jan-2014</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->31-Jan-2014 06:54<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/manual.txt"></script>
<h3><tt>ntpq</tt> - standard NTP query program</h3>
<img src="pic/bustardfly.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>Pogo</i>, Walt Kelly</a>
<p>A typical NTP monitoring packet</p>
-<p>
- <EM>Modified: 31-Jan-2014</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->31-Jan-2014 06:54<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>More Help</h4>
<script type="text/javascript" language="javascript" src="scripts/manual.txt"></script>
<h3><tt>ntptrace</tt> - trace a chain of NTP servers back to the primary source</h3>
<img src="pic/alice13.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>Alice's Adventures in Wonderland</i>, Lewis Carroll</a>
<p>The rabbit knows the way back.</p>
-<p>
- <EM>Modified: 31-Jan-2014</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->31-Jan-2014 06:54<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<hr>
<h4>Synopsis</h4>
<body>
<h3>NTP PARSE clock data formats</h3>
<p>The parse driver currently supports several clocks with different query mechanisms. In order for you to find a sample that might be similar to a clock you might want to integrate into parse I'll sum up the major features of the clocks (this information is distributed in the parse/clk_*.c and ntpd/refclock_parse.c files).</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->21-Oct-2010 23:44<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Meinberg clocks</h4>
<pre>
<body>
<h3>How to build new PARSE clocks</h3>
<p>Here is an attempt to sketch out what you need to do in order to add another clock to the parse driver: Currently the implementation is being cleaned up - so not all information in here is completely correct. Refer to the included code where in doubt.</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->13-Oct-2010 00:33<!-- #EndDate -->
+ UTC</p>
<p>Prerequisites:</p>
<ul>
<li>Does the system you want the clock connect to have the include files termio.h or termios.h ? (You need that for the parse driver)
</head>
<body>
<h3>Poll Process</h3>
-<p>
- <EM>Modified: 15-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:17<!-- #EndDate -->
+ UTC</p>
<hr>
<p>The poll process sends NTP packets at intervals determined by the clock discipline algorithm. The process is designed to provide a sufficient update rate to maximize accuracy while minimizing network overhead. The process is designed to operate over a poll exponent range between 3 (8 s) and 17 (36 hr). The minimum and maximum poll exponent within this range can be set using the <tt>minpoll</tt> and <tt>maxpoll</tt> options of the <a href="confopt.html#option"><tt>server</tt></a> command, with default 6 (64 s) and 10 (1024 s), respectively.</p>
<p> The poll interval is managed by a heuristic algorithm developed over several years of experimentation. It depends on an exponentially weighted average of clock offset differences, called <em>clock jitter</em>, and a jiggle counter, which is initially set to zero. When a clock update is received and the offset exceeds the clock jitter by a factor of 4, the jiggle counter is increased by the poll exponent; otherwise, it is decreased by twice the poll exponent. If the jiggle counter is greater than an arbitrary threshold of 30, it is reset to 0 and the the poll exponent is increased by 1. If the jiggle counter is less than -30, it is set to 0 and the poll exponent decreased by 1. In effect, the algorithm has a relatively slow reaction to good news, but a relatively fast reaction to bad news.</p>
<h3>Pulse-Per-Second (PPS) Signal Interfacing</h3>
<img src="pic/alice32.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html">from <i>Alice's Adventures in Wonderland</i>, Lewis Carroll</a>
<p>Alice is trying to find the PPS signal connector.</p>
-<p>
- <EM>Modified: 15-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:17<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/misc.txt"></script>
<h3>Mitigation Rules and the <tt>prefer</tt> Keyword</h3>
<img src="pic/alice11.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html"> from <i>Alice's Adventures in Wonderland</i>, Lewis Carroll</a>
<p>Listen carefully to what I say; it is very complicated.</p>
-<p>
- <EM>Modified: 15-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:18<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/misc.txt"></script>
<h3>Rate Management and the Kiss-o'-Death Packet</h3>
<img src="pic/boom4.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html">from <i>Pogo</i>, Walt Kelly</a>
<p>Our junior managers and the administrators.</p>
-<p>
- <EM>Modified: 15-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:19<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/hand.txt"></script>
<body>
<h3>Debugging Reference Clock Drivers</h3>
<img src="pic/oz2.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>The Wizard of Oz</i>, L. Frank Baum</a>
-<p>Call the girls and the'll sweep your bugs.</p>
-<p>
- <EM>Modified: 11-Sep-2010</EM>
-</p>
+<p>Call the girls and they'll sweep your bugs.</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:19<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/refclock.txt"></script>
<body>
<h3>Reference Clock Support</h3>
<img src="pic/stack1a.jpg" alt="gif" align="left">Master Time Facility at the <a href="http://www.eecis.udel.edu/%7emills/lab.html">UDel Internet Research Laboratory</a>
-<p>
- <EM>Modified: 01-Mar-2014</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:20<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/hand.txt"></script>
<body>
<em></em>
<h3>Clock Select Algorithm</h3>
-<p>
- <EM>Modified: 15-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:22<!-- #EndDate -->
+ UTC</p>
<hr>
<p>The clock select algorithm determines from a set of sources , which are correct (<em>truechimers</em>) and which are not (<em>falsetickers</em>) according to a set of formal correctness assertions. The principles are based on the observation that the maximum error in determining the offset of a candidate cannot exceed one-half the roundtrip delay to the primary reference clock at the time of measurement. This must be increased by the maximum error that can accumulate since then. The selection metric, called the <em>root distance,</em>, is one-half the roundtrip root delay plus the root dispersion plus minor error contributions not considered here.</p>
<p>First, a number of sanity checks is performed to sift the selectable candidate from among the source population. The sanity checks are sumarized as follows:.</p>
</head>
<body>
<h3>Performance Metrics</h3>
-<p>
- <EM>Modified: 15-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:23<!-- #EndDate -->
+ UTC</p>
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/special.txt"></script>
<script type="text/javascript" language="javascript" src="scripts/external.txt"></script>
</head>
<body>
<h3><tt>tickadj</tt> - set time-related kernel variables</h3>
-<p>
- <EM>Modified: 11-Jul-2011</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:24<!-- #EndDate -->
+ UTC</p>
<hr>
<h4>Synopsis</h4>
<tt>tickadj [ -Aqs ] [ -a <i>tickadj</i> ] [ -t <i>tick</i> ]</tt>
</head>
<body>
<h3>How NTP Works</h3>
-<p>
- <EM>Modified: 15-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:24<!-- #EndDate -->
+ UTC</p>
<h4>Related Links</h4>
<script type="text/javascript" language="javascript" src="scripts/special.txt"></script>
<script type="text/javascript" language="javascript" src="scripts/external.txt"></script>
<h3>NTP Interleaved Modes </h3>
<img src="pic/pogo4.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html">from <i>Pogo</i>, Walt Kelly</a>
<p>You need a little magic.</p>
-<p>
- <EM>Modified: 15-Nov-2012</EM>
-</p>
+<p>Last update:
+ <!-- #BeginDate format:En2m -->10-Mar-2014 05:25<!-- #EndDate -->
+ UTC</p>
<br clear="left">
<hr>
<p>In the protocol described in the NTP specification and reference implementation up to now, the transmit timestamp, which is captured before the message digest is computed and the packet queued for output, is properly called as a <em>softstamp</em> The receive timestamp, which is captured after the input driver interrupt routine and before the packet is queued for input, is properly called a <em>drivestamp</em>. For enhanced accuracy it is desirable to capture the transmit timestamp as close to the wire as possible; for example, after the output driver interrupt routine.</p>
projects / thirdparty / ntp.git / commitdiff
