Proceedings ArticleDOI
Enhancements to the time synchronization standard IEEE-1588 for a system of cascaded bridges
Jurgen Jasperneite,K. Shehab,Karl Weber +2 more
- pp 239-244
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TLDR
In this paper, a bypass clock instead of the boundary clock is proposed as an enhancement of the IEEE-1588 standard for bridged networks, where the local clock adjustment can be modeled by a corresponding control loop.Abstract:
The IEEE-1588 standard for a high precision time synchronization now exists since 2002. For using this standard in bridged networks a so-called boundary clock is defined, where the local clock adjustment can be modeled by a corresponding control loop. At the field level of industrial automation systems, the line topology is very important. By using Ethernet at the field level, the resulting chain of bridges leads to a cascade of control loops and may lead to instabilities and deviations of the distributed clocks, which are not acceptable. For this application a bypass clock instead of the boundary clock is proposed as an enhancement of the IEEE-1588 standard. The effectiveness of this extension to be evaluated by simulation technique.read more
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References
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Journal ArticleDOI
Internet time synchronization: the network time protocol
TL;DR: The NTP synchronization system is described, along with performance data which show that timekeeping accuracy throughout most portions of the Internet can be ordinarily maintained to within a few milliseconds, even in cases of failure or disruption of clocks, time servers, or networks.
Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems
Kang B. Lee,J Eldson +1 more
TL;DR: A protocol is provided in this standard that enables precise synchronization of clocks in measurement and control systems implemented with technologies such as network communication, local computing, and distributed objects.
Proceedings ArticleDOI
IEEE 1588 standard for a precision clock synchronization protocol for networked measurement and control systems
J C. Eidson,Kang B. Lee +1 more
TL;DR: This paper discusses the major features and design objectives of the IEEE-1588 standard, designed to serve the clock synchronization needs of industrial systems, and recent performance results of prototype implementations of this standard in an Ethernet environment are presented.
Journal ArticleDOI
Precision synchronization of computer network clocks
TL;DR: In this article, the authors describe a series of incremental improvements in system hardware and software which result in significantly better accuracy and stability, especially in primary time servers directly synchronized to radio or satellite time services.