devine@cookie.dec.com (Bob Devine) (02/26/88)
> I am looking for articles, references, implementations, > etc. for solving the problem of keeping N machines within > a specified time of one another. I appreciate any and all >pointers. First, recognize that "synchronization" does not necessarily mean "accuracy". All clocks may be correctly synchronized but to a time that is wrong. Here is a list of products that will give you the time from National Bureau of Standard's broadcasts over WWV, WWVB, WWVH... "The Time Source" Precision Standard Time Inc. Fremont CA "Precision Timekeeping System" Spectracom Corp. East Rochester, NY Radio Shack still might have something too Some technical papers (presented in order of guessed use to you): Lindsey et al.; "Network Synchronization" Proceedings of the IEEE Vol.73 Num.10 Oct. 1985 Riccardo Gusella and Stefano Zatti; "Tempo: A Network Time Controller for a Distributed Berkeley Unix System" 1984 Summer Usenix Proceedings Keith Marzullo and Susan Owicki; "Maintaining the Time in a Distributed System" Proceedings of the 2nd ACM Symposium on Principles of Distributed Computing, 1983 Glenn Ricart and Ashok Agrawala; "An Optimal Algorithm for Mutual Exclusion in Computer Networks" CACM, Jan. 1981 David Jefferson; "Virtual Time" ACM Trans on Prog Langs and Systems July 1985 Leslie Lamport; "Time, Clocks, and the Orderings of Events in a Distributed System" CACM July 1978 Leslie Lamport and P.M. Melliar-Smith; "Synchronizing Clocks in the Presence of Faults" Journal of ACM, Jan 1985 Leslie Lamport and P.M. Melliar-Smith; "Byzantine Clock Synchronization" ACM Operating System Review, July 1986 There are some papers written by Dave Mills that you can get from the NIC (send mail to ...!ucbvax!SRI-NIC.ARPA!NIC). The RFCs are 956 Algorithms for Synchronizing Network Clocks 957 Experiments in Network Clock Synchronization 958 Network Time Protocol Bob Devine