Initial experiences with a clock synchronisation test bed
Paul Ashton, J.D. Mackenzie · 1998
In a distributed system, no hardware facilities exist to synchronise the clocks of the computers within the system. Algorithms designed to synchronise clocks in such systems have been the subject of much research. The lack of a global clock has meant that the accuracy of these algorithms has generally been assessed using indirect measures of clock o#sets. We have developed a clock synchronisation test bed that allows for direct measurement of clock o#sets. The test bed is now operational, and we have used it to produce initial results for the widely-used xntp package, and for some o#-line synchronisation algorithms. 1 Introduction Clock synchronisation in distributed computer systems is a widely studied problem. The primary aim of a clock synchronisation algorithm is to ensure that the maximum di#erence (or o#set) between any two clocks amongst a group of clocks being synchronised is small. Di#erent applications have di#erent requirements as to the degree to which clocks must...