1181834SrobertoNotes for NTP Version 3 2181834Sroberto 3181834SrobertoThis version operates in much the same manner as Version 2 with the 4181834Srobertofollowing changes and additions: 5181834Sroberto 6181834Sroberto1. The protocol machinery operates in conformance with the RFC1305 NTP 7181834Sroberto Version 3 specification. The most visible characteristic of this 8181834Sroberto version is that the poll intervals for all polls, even selected 9181834Sroberto ones, is significantly increased. This is especially desirable when 10181834Sroberto serving a large client population. This implementation supports 11181834Sroberto previous versions as non-configured peers; for version-2 configured 12181834Sroberto peers a "version 2" keyword should be included on the "peer" line. 13181834Sroberto 14181834Sroberto2. The configuration file has a new keyword: statfile <file>, where 15181834Sroberto <file> is the name of a statistics file." When present, each clock 16181834Sroberto update generates an entry of the form: 17181834Sroberto 18181834Sroberto <day> <sec>.<frac> <addr> <status> <offset> <delay> <disp> 19181834Sroberto 20181834Sroberto where <day> is the modified Julian day, <sec>.<frac> is the time of 21181834Sroberto day, <addr> is the peer address and <status> is the peer status. 22181834Sroberto The <offset>, <delay> and <disp> are the measured offset, delay and 23181834Sroberto dispersion, respectively, of the peer clock relative to the local 24181834Sroberto clock. About once per day the current file is closed and a new one 25181834Sroberto created with names <file>.<gen>, where <gen> starts at one and 26181834Sroberto increments for each new generation. 27181834Sroberto 28181834Sroberto3. A number of additional platforms are supported. See ./Config file 29181834Sroberto for details. 30181834Sroberto 31181834Sroberto4. A driver for the TrueTime 468DC GOES Synchronized Clock is 32181834Sroberto included. This driver (refclock_goes.c) should also work for other 33181834Sroberto TrueTime radio clocks, since all use the same format. 34181834Sroberto 35181834Sroberto5. A replacement driver for the Spectracom 8170 WWVB Synchronized 36181834Sroberto Clock is included. This driver (refclock_wwvb.c) (a) does not 37181834Sroberto require a 1-pulse-per-second signal, (b) supports both format 0 38181834Sroberto (original 8170) and format 2 (Netclock/2 and upgraded 8170), (c) 39181834Sroberto can be connected to more than one computer and (d) automatically 40181834Sroberto compensates for all serial baud rates. 41181834Sroberto 42181834Sroberto6. A driver for the German time/frequency station DCF77 is included. 43181834Sroberto This requires a special STREAMS module. 44181834Sroberto 45181834Sroberto7. In Version 2 special line-discipline modules were required for the 46181834Sroberto CHU and WWVB drivers. This code continues to work in Version 3, 47181834Sroberto although it is no longer needed for the WWVB driver. However, this 48181834Sroberto code does not work under STREAMS, as used in SunOS 4.1.1. 49181834Sroberto Equivalent STREAMS modules are supplied with Version 3. 50181834Sroberto 51181834Sroberto8. Support for an external 1-pulse-per-second (pps) signal is 52181834Sroberto provided. The signal is connected to a serial port (see 53181834Sroberto xntpd/ntp_loopfilter.c for details). When present the leading edge 54181834Sroberto of the pulse establishes the on-time epoch within an interval 55181834Sroberto established by the selected radio clock or other NTP time server. 56181834Sroberto Use of the pps is indicated when the tattletale displayed by ntpq 57181834Sroberto changes from "*" to "o". 58181834Sroberto 59181834Sroberto9. The clock-selection and poll-update procedures have been modified 60181834Sroberto slightly in order to achieve better performance on high speed LANs 61181834Sroberto with compromise in performance on typical WANs. 62181834Sroberto 63181834Sroberto10. In order to comply with U.S. Commerce Department regulations, the DES 64181834Sroberto encryption routine lib/authdes.c cannot be exported. For exportable 65181834Sroberto versions of this distribution a DES-encrypted version of this routine 66181834Sroberto lib/authdes.c.des is included along with an unencrypted version 67181834Sroberto lib/authdes.c.export, which allows normal operation, but without the 68181834Sroberto NTP authentication feature. Further information is available in the 69181834Sroberto lib/authdes.c.export file. 70181834Sroberto 71181834Sroberto11. As an alternative to the DES-based authentication mechanism, an 72181834Sroberto implementation of the RSA Message Digest 5 algorithm is provided. 73181834Sroberto (see applicable copyright information in the library files). 74181834Sroberto 75181834Sroberto12. A driver for the Magnavox MX4200 GPS clock. 76181834Sroberto 77181834Sroberto13. A STREAMS module which captures carrier-detect data-lead transitions to 78181834Sroberto connect a precision source of 1-pps, yet avoid the ugly overhead in the 79181834Sroberto usual STREAMS processing. See the ppsclock subdirectory. 80181834Sroberto 81181834Sroberto14. Support for the Apple A/UX operating system and enhanced support for the 82181834Sroberto Hewlet-Packard HP/UX operating system. See the various README and Config 83181834Sroberto files for further information. 84181834Sroberto 85181834SrobertoSee the COPYRIGHT file for authors and copyright information. Note that some 86181834Srobertomodules in this distribution contain copyright information that supersedes 87181834Srobertothe copyright information in that file. 88181834Sroberto 89181834SrobertoIf I missed something or neglected to give due credit, please advise. 90181834Sroberto 91181834SrobertoDavid L. Mills 92181834SrobertoUniversity of Delaware 93181834Sroberto31 May 1992, amended 23 July 1992, 25 October 1992 94181834Sroberto 95181834SrobertoBugs and notes 96181834Sroberto 97181834SrobertoA bug in the original tty_clk_STREAMS.c module has been fixed. 98181834Sroberto 99181834SrobertoThe poll-interval randomization feature of poll_update (in 100181834Srobertoxntpd/ntp_proto.c) has been extended to apply when the poll interval is 101181834Srobertoincreased, as well as reduced. This spreads the update messages in time 102181834Srobertoand helps avoid unpleasant bursts of messages. 103181834Sroberto 104181834SrobertoIn the clock_select algorithm the peers selected for combining are 105181834Srobertolimited to those survivors at the lowest stratum, not the entire list. 106181834SrobertoThis helps avoid whiplash when large numbers of peers are at the same 107181834Srobertostratum. 108181834Sroberto 109181834SrobertoThe number formerly displayed by ntpq as "compliance" is now the time 110181834Srobertoconstant of integration. 111181834Sroberto 112181834SrobertoThe DNS resolver xntpd/ntp_intres.c is now integrated into xntpd, making 113181834Srobertoconfiguration of multiple hosts easier. 114181834Sroberto 115181834SrobertoSystem and peer event are now written to the system log at priority 116181834SrobertoLOG_INFO. 117181834Sroberto 118181834SrobertoThe leap-second code was fixed to avoid broadcasting leap warnings on 119181834Srobertoall except the last day of June and December. 120