mills@DCN6.ARPA (09/09/85)
Folks, I am proposing a new protocol for distributing network time. It is called the Network Time Protocol (NTP) and described in a document suitable for distribution as an RFC. The document is in TIMPRO.DOC in the MILLS directory at ISID. Background information, along with experimental data and algorithm designs, is in two companion documents TIME.DOC and SYNCH.DOC. I have implemented prototype servers and testing programs, which are running now on DCN1.ARPA (WWVB clock), DCN6.ARPA (WWV clock), FORD1.ARPA (GOES clock) and IPTO-FAX.ARPA (line-frequency clock). NTP specifies data formats and message-transfer procedures only. It does not specify the local timekeeping or network distribution algorithms. Accurate timetelling to fractions of a second requires carefully managed timekeeping mechanisms such as described in TIME.DOC and RFC-889. The interesting area remaining is the network distribution algorithms appropriate for a large, hierarchical community of hosts to maintain and distribute accurate time, in spite of some timetellers that are less accurate than others and even some that might refuse, lie or die. Suggested algorithms to filter unreliable or noisy data are included in SYNCH.DOC, while an outline for a distributed algorithm for network management is included in TIMPRO.DOC. This note is to invite discussion and comment in the relevant task forces and message groups before the paint dries on the the protocol document and it is generally distributed. My hope is to do this while continuing to experiment and define the distribution algorithm, so I would like to keep the discussion period short. I have found this area a useful model for studying and experimenting with robust, distributed protocols while keeping implementation overheads low. Comments and suggestions to this mailbox (mills@dcn6.arpa) would be appreciated and will be combined for redistribution. Dave -------
klute%gatech.csnet@CSNET-RELAY.ARPA (Gregory Kenley) (09/10/85)
Dave, I am very interested in your latest posting. However since I don't have ARPA access I cannot get at these documents. Would you please send the sources to me as mail? I would appreciate it a lot. I would very much like to see what you have done. Thanks.