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diff --git a/contrib/ntp/html/index.htm b/contrib/ntp/html/index.htm index c5cca91..680cec8 100644 --- a/contrib/ntp/html/index.htm +++ b/contrib/ntp/html/index.htm @@ -1,201 +1,261 @@ -<html><head><title> -The Network Time Protocol (NTP) Distribution -</title></head><body><h3> -The Network Time Protocol (NTP) Distribution -</h3> - -<IMG align=left SRC=pic/barnstable.gif>From <i>pogo</i>, Walt Kelly - -<p>Pleased to meet you. -<BR clear=left><HR> - -<H4>Introduction</H4> - -Note: The software contained in this distribution is available without -charge under the conditions set forth in the <A -HREF=copyright.htm>Copyright Notice</A>. - -<P>The Network Time Protocol (NTP) is used to synchronize the time of a -computer client or server to another server or reference time source, -such as a radio or satellite receiver or modem. It provides client -accuracies typically within a millisecond on LANs and up to a few tens -of milliseconds on WANs relative to a primary server synchronized to -Coordinated Universal Time (UTC) via a Global Positioning Service (GPS) -receiver, for example. Typical NTP configurations utilize multiple -redundant servers and diverse network paths, in order to achieve high -accuracy and reliability. Some configurations include cryptographic -authentication to prevent accidental or malicious protocol attacks. - -<P>Background information on computer network time synchronization can -be found on the <A HREF=exec.htm>Executive Summary - Computer Network -Time Synchronization</A> page. Discussion on protocol conformance issues -and interoperability with previous NTP versions can be found in the <A -HREF=biblio.htm>Protocol Conformance Statement</A> page. Discussion on -year-2000 issues can be found in the <A HREF=y2k.htm>Year 2000 -Conformance Statement page</A>. Background information, bibliography and -briefing slides suitable for presentations can be found in the <A -HREF=http://www.eecis.udel.edu/~mills/ntp.htm> Network Time -Synchronization Project</A> page. - -<H4>Building and Installing NTP</H4> - -The <A HREF=build.htm>Building and Installing the Distribution -</A>page presents an overview of the procedures for compiling the -distribution and installing it on a typical client or server. The build -procedures inspect the system hardware and software environment and -automatically select the appropriate options for that environment. While -these procedures work with most computers and operating systems marketed -today, exceptions requiring manual intervention do exist, as documented -in the <A HREF=config.htm>Configuration Options </A>and <A -HREF=release.htm>Release Notes </A>pages. - -<P>Bringing up a NTP primary server requires a radio or satellite -receiver or modem. The distribution includes hardware drivers for over -two dozen radio clocks and modem services. A list of the particular -receivers and modem drivers supported in the distribution is given in -the <A HREF=refclock.htm>Reference Clock Drivers </A>page. For most -popular workstations marketed by Digital, Sun and Hewlett Packard, as -well as widely available Unix clones such as FreeBSD and Linux, the -automatic build procedures select all drivers that run on the target -machine. While this increases the size of the executable binary -somewhat, individual drivers can be included or excluded using the -configure utility documented in the Configuration Options page. - -<H4>Configuring Clients and Servers</H4> -<p>NTP is by its very nature a complex distributed network application -and can be configured and used for a great many widely divergent -timekeeping scenarios. The documentation presented on these pages -attempts to cover the entire suite of configuration, operation and -maintenance facilities which this distribution supports. However, most -applications will need only a few of these facilities. If this is the -case, the <a href=quick.htm>Quick Start</a> page may be useful to get a -simple workstation on the air with an existing server. - -<p>However, in order to participate in the existing NTP synchronization -subnet and obtain accurate, reliable time, it is usually necessary to -construct an appropriate configuration file, commonly called -<TT>ntp.conf</TT>, which establishes the servers and/or external -receivers or modems to be used by this particular machine. Directions -for constructing this file are in the <A HREF=notes.htm>Notes on -Configuring NTP and Setting up a NTP Subnet </A>page. However, in many -common cases involving simple network topologies and workstations, the -file data can be specified entirely on the command line. - -<P>The most important factor in providing accurate, reliable time is the -selection of modes and servers to be used in the configuration file. NTP -support for one or more computers is normally engineered as part of the -existing NTP synchronization subnet. The existing NTP subnet consists of -a multiply redundant hierarchy of servers and clients, with each level -in the hierarchy identified by stratum number. Primary servers operate -at stratum one and provide synchronization to secondary servers -operating at stratum two and so on to higher strata. In this hierarchy, -clients are simply servers that have no dependents. - -<P>The NTP subnet in early 1998 includes 70 public primary (stratum 1) -servers synchronized directly to UTC by radio, satellite or modem and -located in every continent of the globe, except Antarctica (soon). -Normally, client workstations and servers with a relatively small number -of clients do not synchronize to primary servers. There are 106 public -secondary (stratum 2) servers synchronized to the primary servers and -providing synchronization to a total in excess of 100,000 clients and -servers in the Internet. The current lists are maintained in the <A -HREF=http://www.eecis.udel.edu/~mills/ntp/index.htm>Information on Time -and Frequency Services</A> page, which is updated frequently. There are -numerous private primary and secondary servers not normally available to -the public as well. You are strongly discouraged from using these -servers, since they sometimes hide in little ghettos behind dinky links -to the outside world and your traffic can bring up expensive ISDN lines, -causing much grief and frustration. - -<H4>Resolving Problems</H4> - -Like other things Internet, the NTP synchronization subnets tend to be -large and devilishly intricate, with many opportunities for +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"> +<html> +<head> +<meta name="generator" content="HTML Tidy, see www.w3.org"> +<title>The Network Time Protocol (NTP) Distribution</title> +</head> +<body> +<h3>The Network Time Protocol (NTP) Distribution</h3> + +<img align="left" src="pic/barnstable.gif" alt="gif"><a href= +"http://www.eecis.udel.edu/~mills/pictures.htm"><i>P.T. Bridgeport +Bear</i>; from <i>Pogo</i>, Walt Kelly</a> + +<p>Pleased to meet you.<br clear="left"> +</p> + +<hr> +<h4>Introduction</h4> + +Note: The software contained in this distribution is available +without charge under the conditions set forth in the <a href= +"copyright.htm">Copyright Notice</a>. + +<p>The Network Time Protocol (NTP) is used to synchronize the time +of a computer client or server to another server or reference time +source, such as a radio or satellite receiver or modem. It provides +accuracies typically within a millisecond on LANs and up to a few +tens of milliseconds on WANs relative to Coordinated Universal Time +(UTC) via a Global Positioning Service (GPS) receiver, for example. +Typical NTP configurations utilize multiple redundant servers and +diverse network paths in order to achieve high accuracy and +reliability. Some configurations include cryptographic +authentication to prevent accidental or malicious protocol attacks +and some provide automatic server discovery using IP multicast.</p> + +<p>Background information on computer network time synchronization +can be found on the <a href="exec.htm">Executive Summary - Computer +Network Time Synchronization</a> page. Discussion on protocol +conformance issues and interoperability with previous NTP versions +can be found in the <a href="biblio.htm">Protocol Conformance +Statement</a> page. Discussion on how NTP reckons the time can be +found in the <a href="leap.htm">NTP Timescale and Leap Seconds</a> +page. Background information, bibliography and briefing slides +suitable for presentations can be found in the <a href= +"http://www.eecis.udel.edu/~mills/ntp.htm">Network Time +Synchronization Project</a> page. Additional information can be +found at the NTP web site <a href="http://www.ntp.org"> +www.ntp.org</a>. Please send bug reports to <a href= +"mailto:bugs@mail.ntp.org"><bugs@mail.ntp.org></a>.</p> + +<h4>Building and Installing NTP</h4> + +NTP supports Unix and Windows (NT4 and 2000) systems. The <a href= +"build.htm">Building and Installing the Distribution</a> page +presents an overview of the procedures for compiling the +distribution and installing it on a typical client or server. The +build procedures inspect the system hardware and software +environment and automatically select the appropriate options for +that environment. While these procedures work with most computers +and operating systems marketed today, exceptions requiring manual +intervention do exist, as documented in the <a href="config.htm"> +Configuration Options</a> and <a href="release.htm">Release +Notes</a> pages. Note that support for strong cryptography requires +cryptographic libraries not included in this distribution. + +<p>Bringing up a NTP primary server requires a radio or satellite +receiver or modem. It is also possible to configure a machine on an +isolated network with the local clock driver and have other +machines synchronize to it. The distribution includes hardware +drivers for the local clock and over three dozen radio clocks and +modem services. A list of supported drivers is given in the <a +href="refclock.htm">Reference Clock Drivers</a> page. For most +popular workstations marketed by Digital/Compaq, Sun and Hewlett +Packard, as well as widely available Unix clones such as FreeBSD +and Linux, the automatic build procedures select all drivers that +run on the target machine. While this increases the size of the +executable binary somewhat, individual drivers can be included or +excluded using the configure utility documented in the +Configuration Options page.</p> + +<h4>Configuring Clients and Servers</h4> + +<p>NTP is by its very nature a complex distributed network +application and can be configured and used for a great many widely +divergent timekeeping scenarios. The documentation presented on +these pages attempts to cover the entire suite of configuration, +operation and maintenance facilities which this distribution +supports. However, most applications will need only a few of these +facilities. If this is the case, the <a href="quick.htm">Quick +Start</a> page may be useful to get a simple workstation on the air +with an existing server.</p> + +<p>However, in order to participate in the existing NTP +synchronization subnet and obtain accurate, reliable time, it is +usually necessary to construct an appropriate configuration file, +commonly called <tt>ntp.conf</tt>, which establishes the servers +and/or external receivers or modems to be used by this particular +machine. Directions for constructing this file are in the <a href= +"notes.htm">Notes on Configuring NTP and Setting up a NTP +Subnet</a> page. However, in many common cases involving simple +network topologies and workstations, the configuration data can be +specified entirely on the command line for the <a href="ntpd.htm"> +<tt>ntpd</tt> - Network Time Protocol (NTP) daemon</a>.</p> + +<p>The most important factor in providing accurate, reliable time +is the selection of modes and servers to be used in the +configuration file. A discussion on the available modes is on the +<a href="assoc.htm">Association Management</a> page. NTP support +for one or more computers is normally engineered as part of the +existing NTP synchronization subnet. The existing NTP subnet +consists of a multiply redundant hierarchy of servers and clients, +with each level in the hierarchy identified by stratum number. +Primary servers operate at stratum one and provide synchronization +to secondary servers operating at stratum two and so on to higher +strata. In this hierarchy, clients are simply servers that have no +dependents.</p> + +<p>The NTP subnet in late 2000 includes over a hundred public +primary (stratum 1) servers synchronized directly to UTC by radio, +satellite or modem and located in every continent of the globe, +including Antarctica. Normally, client workstations and servers +with a relatively small number of clients do not synchronize to +primary servers. There are over a hundred public secondary (stratum +2) servers synchronized to the primary servers and providing +synchronization to a total in excess of 100,000 clients and servers +in the Internet. The current lists are maintained in the <a href= +"http://www.eecis.udel.edu/~mills/ntp/index.htm">Information on +Time and Frequency Services</a> page, which is updated frequently. +There are numerous private primary and secondary servers not +normally available to the public as well. You are strongly +discouraged from using these servers, since they sometimes hide in +little ghettos behind dinky links to the outside world and your +traffic can bring up expensive ISDN lines, causing much grief and +frustration.</p> + +<h4>Resolving Problems</h4> + +Like other things Internet, the NTP synchronization subnets tend to +be large and devilishly intricate, with many opportunities for misconfiguration and network problems. The NTP engineering model is -specifically designed to help isolate and repair such problems using an -integrated management protocol, together with a suite of monitoring and -debugging tools. There is an optional data recording facility which can -be used to record normal and aberrant operation, log problems to the -system log facility, and retain records of client access. The <A -HREF=debug.htm>NTP Debugging Techniques </A>and <A -HREF=hints.htm>Hints and Kinks </A>pages contain useful information -for identifying problems and devising solutions. - -<P>Users are requested to report bugs, offer suggestions and contribute -additions to this distribution. The <A HREF=patches.htm>Patching -Procedures </A>page suggests procedures which greatly simplify -distribution updates, while the <A HREF=porting.htm>Porting Hints -</A>page suggest ways to make porting this code to new hardware and -operating systems easier. Additional information on reference clock -driver construction and debugging can be found in the <A -HREF=refclock.htm>Reference Clock Drivers </A>page. Further -information on NTP in the Internet can be found in the <A -HREF=http://www.eecis.udel.edu/~ntp>NTP -web page</A>. - -<H4>Program Manual Pages</H4> +specifically designed to help isolate and repair such problems +using an integrated management protocol, together with a suite of +monitoring and debugging tools. There is an optional data recording +facility which can be used to record normal and aberrant operation, +log problems to the system log facility, and retain records of +client access. The <a href="debug.htm">NTP Debugging Techniques</a> +and <a href="hints.htm">Hints and Kinks</a> pages contain useful +information for identifying problems and devising solutions. + +<p>Users are requested to report bugs, offer suggestions and +contribute additions to this distribution. The <a href= +"patches.htm">Patching Procedures</a> page suggests procedures +which greatly simplify distribution updates, while the <a href= +"porting.htm">Porting Hints</a> page suggest ways to make porting +this code to new hardware and operating systems easier. Additional +information on reference clock driver construction and debugging +can be found in the <a href="refclock.htm">Reference Clock +Drivers</a> page. Further information on NTP in the Internet can be +found in the <a href="http://www.eecis.udel.edu/~ntp">NTP web +page</a>.</p> + +<h4>Program Manual Pages</h4> <ul> +<li><a href="ntpd.htm"><tt>ntpd</tt> - Network Time Protocol (NTP) +daemon</a></li> + +<li><a href="ntpq.htm"><tt>ntpq</tt> - standard NTP query +program</a></li> + +<li><a href="ntpdc.htm"><tt>ntpdc</tt> - special NTP query +program</a></li> + +<li><a href="ntpdate.htm"><tt>ntpdate</tt> - set the date and time +via NTP</a></li> -<li><A HREF=ntpd.htm><TT>ntpd</TT> - Network Time Protocol (NTP) -daemon</A></LI> -<LI><A HREF=ntpq.htm><TT>ntpq</TT> - standard NTP query -program</A></LI> -<LI><A HREF=ntpdc.htm><TT>ntpdc</TT> - special NTP query -program</A></LI> -<LI><A HREF=ntpdate.htm><TT>ntpdate</TT> - set the date and time via -NTP</A></LI> -<LI><A HREF=ntptrace.htm><TT>ntptrace</TT> - trace a chain of NTP -servers back to the primary source</A></LI> -<LI><A HREF=tickadj.htm><TT>tickadj</TT> - set time-related kernel -variables</A></LI> -<LI><A HREF=ntptime.htm><TT>ntptime</TT> - read kernel time -variables</A></LI> +<li><a href="ntptrace.htm"><tt>ntptrace</tt> - trace a chain of NTP +servers back to the primary source</a></li> +<li><a href="tickadj.htm"><tt>tickadj</tt> - set time-related +kernel variables</a></li> + +<li><a href="ntptime.htm"><tt>ntptime</tt> - read kernel time +variables</a></li> + +<li><a href="genkeys.htm"><tt>ntp-genkeys</tt> - generate public +and private keys</a></li> </ul> -<H4>Supporting Documentation</H4> +<h4>Supporting Documentation</h4> <ul> +<li><a href="http://www.eecis.udel.edu/~mills/ntp.htm">NTP Project +and Reference Library</a></li> + +<li><a href="copyright.htm">Copyright Notice</a></li> + +<li><a href="exec.htm">Executive Summary - Computer Network Time +Synchronization</a></li> + +<li><a href="biblio.htm">Protocol Conformance Statement</a></li> + +<li><a href="leap.htm">NTP Timescale and Leap Seconds</a></li> + +<li><a href="notes.htm">Notes on Configuring NTP and Setting up a +NTP Subnet</a></li> + +<li><a href="release.htm">NTP Version 4 Release Notes</a></li> + +<li><a href="build.htm">Building and Installing the +Distribution</a></li> + +<li><a href="config.htm">Configuration Options</a></li> -<LI<A HREF=ntp.htm>NTP Reference Library</A></LI> -<LI><A HREF=copyright.htm>Copyright Notice</A></LI> -<LI><A HREF=exec.htm>Executive Summary - Computer Network Time -Synchronization</A></LI> -<LI><A HREF=biblio.htm>Protocol Conformance Statement</A></LI> -<LI><A HREF=y2k.htm>Year 2000 Conformance Statement</A></LI> -<LI><A HREF=notes.htm>Notes on Configuring NTP and Setting up a NTP -Subnet</A></LI> -<LI><A HREF=release.htm>NTP Version 4 Release Notes</A></LI> -<LI><A HREF=build.htm>Building and Installing the -Distribution</A></LI> -<LI><A HREF=config.htm>Configuration Options</A></LI> -<LI><A HREF=debug.htm>NTP Debugging Techniques</A></LI> -<LI><A HREF=refclock.htm>Reference Clock Drivers</A></LI> -<LI><A HREF=patches.htm>Patching Procedures</A></LI> -<LI><A HREF=hints.htm>Hints and Kinks</A></LI> -<LI><A HREF=porting.htm>Porting Hints</A></LI> +<li><a href="debug.htm">NTP Debugging Techniques</a></li> +<li><a href="refclock.htm">Reference Clock Drivers</a></li> + +<li><a href="patches.htm">Patching Procedures</a></li> + +<li><a href="hints.htm">Hints and Kinks</a></li> + +<li><a href="porting.htm">Porting Hints</a></li> </ul> -<H4>Application Notes</H4> +<h4>Application Notes</h4> <ul> +<li><a href="prefer.htm">Mitigation Rules and the <tt>prefer</tt> +Keyword</a></li> + +<li><a href="assoc.htm">Association Management</a></li> + +<li><a href="pps.htm">Pulse-per-second (PPS) Signal +Interfacing</a></li> -<LI><A HREF=prefer.htm>Mitigation Rules and the <TT>prefer</TT> -Keyword</A></LI> -<LI><A HREF=assoc.htm>Association Management</A></LI> -<LI><A HREF=pps.htm>Pulse-per-second (PPS) Signal Interfacing</A></LI> -<LI><A HREF=gadget.htm>Gadget Box PPS Level Converter and CHU -Modem</A></LI> -<LI><A HREF=measure.htm>Time and Time Interval Measurement with -Application to Computer and Network Performance Evaluation</A></LI> -<LI><A HREF=kern.htm>A Kernel Model for Precision Timekeeping</A></LI> -<LI><A HREF=kernpps.htm>A Kernel Programming Interface for Precision -Time Signals</A></LI> +<li><a href="gadget.htm">Gadget Box PPS Level Converter and CHU +Modem</a></li> +<li><a href="measure.htm">Time and Time Interval Measurement with +Application to Computer and Network Performance Evaluation</a></li> + +<li><a href="kern.htm">Kernel Model for Precision +Timekeeping</a></li> + +<li><a href="kernpps.htm">Kernel Programming Interface for +Precision Time Signals</a></li> </ul> -<hr><a href=index.htm><img align=left src=pic/home.gif></a><address><a -href=mailto:mills@udel.edu> David L. Mills <mills@udel.edu></a> -</address></a></body></html> +<hr> +<center><img src="pic/pogo1a.gif" alt="gif"></center> + +<br> +<a href="index.htm"><img align="left" src="pic/home.gif" alt= +"gif"></a> + +<address><a href="mailto:mills@udel.edu">David L. Mills +<mills@udel.edu></a></address> +</body> +</html> + |
