Embedded System Design for Network Time Synchronization
Every computer needs a timer mechanism to keep track of current time and also for various accounting purposes such as calculating the time spent by a process in CPU utilization, disk I/O, and so on, so that the corresponding user can be charged properly. In a distributed system, an application may have processes that concurrently run on multiple nodes of the system. For correct results, several such distributed applications require that the clocks of the nodes are synchronized with each other. Nowadays, time synchronization has been a compulsory thing as distributed processing and network operations are generalized. A network time server obtains, keeps accurate and precise time by synchronizing its local clock to a standard reference time source and distributes time information through a standard time synchronization protocol. This paper describes design issues and implementation of an embedded system for network time synchronization especially based on a clock model. Our system uses GPS (Global Positioning System) as a standard reference time source and offers UTC (Coordinated Universal Time) through the NTP (Network Time Protocol). Implementation results and performance evaluation are also presented.
KeywordsGlobal Position System Time Synchronization Global Position System Satellite Clock Model Local Clock
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