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Kang B. Lee

Bio: Kang B. Lee is an academic researcher. The author has contributed to research in topics: Clock synchronization & Synchronization. The author has an hindex of 3, co-authored 5 publications receiving 2534 citations.

Papers
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27 Sep 2004
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.
Abstract: 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. The protocol is applicable to systems communicating via packet networks. Heterogeneous systems are enabled that include clocks of various inherent precision, resolution, and stability to synchronize. System-wide synchronization accuracy and precision in the sub-microsecond range are supported with minimal network and local clock computing resources. Simple systems are installed and operated without requiring the management attention of users because the default behavior of the protocol allows for it.

1,428 citations

Proceedings ArticleDOI
05 Dec 2002
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.
Abstract: This paper discusses the major features and design objectives of the IEEE-1588 standard. Recent performance results of prototype implementations of this standard in an Ethernet environment are presented. Potential areas of application of this standard are outlined.

1,112 citations

Journal ArticleDOI
TL;DR: It is shown that sub-microsecond synchronization accuracy is readily achieved using the IEEE 1588 protocol and some of the ways in which this common sense of time may be exploited in time-based measurement and control applications are suggested.
Abstract: We outline three architectures for establishing system timing used in both the general computing environment and in the more specialized environment of test, measurement, and industrial control. Increasingly tight synchronization requirements and the trend to more distributed and peer-to-peer applications have led to the development of the IEEE 1588 standard as a means of establishing a precise common sense of time in the test, measurement, and industrial control environment. We suggest some of the ways in which this common sense of time may be exploited in time-based measurement and control applications. It is shown that sub-microsecond synchronization accuracy is readily achieved using the protocol.

53 citations


Cited by
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Proceedings ArticleDOI
05 Dec 2002
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.
Abstract: This paper discusses the major features and design objectives of the IEEE-1588 standard. Recent performance results of prototype implementations of this standard in an Ethernet environment are presented. Potential areas of application of this standard are outlined.

1,112 citations

Journal ArticleDOI
31 May 2005
TL;DR: This paper details the requirements that an industrial network has to fulfill and shows how Ethernet has been enhanced to comply with the real-time requirements in particular in the industrial context.
Abstract: Despite early attempts to use Ethernet in the industrial context, only recently has it attracted a lot of attention as a support for industrial communication. A number of vendors are offering industrial communication products based on Ethernet and TCP/IP as a means to interconnect field devices to the first level of automation. Others restrict their offer to communication between automation devices such as programmable logic controllers and provide integration means to existing fieldbuses. This paper first details the requirements that an industrial network has to fulfill. It then shows how Ethernet has been enhanced to comply with the real-time requirements in particular in the industrial context. Finally, we show how the requirements that cannot be fulfilled at layer 2 of the OSI model can be addressed in the higher layers adding functionality to existing standard protocols.

452 citations

Proceedings ArticleDOI
24 May 2009
TL;DR: Use cases for interoperability, as well as work-in-progress around inter-cloud protocols and formats for enabling those use cases, are discussed in this paper.
Abstract: Cloud Computing is a term applied to large, hosted datacenters, usually geographically distributed, which offer various computational services on a “utility” basis. Most typically the configuration and provisioning of these datacenters, as far as the services for the subscribers go, is highly automated, to the point of the service being delivered within seconds of the subscriber request. Additionally, the datacenters typically use hypervisor based virtualization as a technique to deliver these services. The concept of a cloud operated by one service provider or enterprise interoperating with a clouds operated by another is a powerful idea. So far that is limited to use cases where code running on one cloud explicitly references a service on another cloud. There is no implicit and transparent interoperability. Use cases for interoperability, as well as work-in-progress around inter-cloud protocols and formats for enabling those use cases, are discussed in this paper.

419 citations

Journal ArticleDOI
31 May 2005
TL;DR: After more than ten years of experience with applications of fieldbus in automation technology, the industry has started to develop and adopt Real-Time Ethernet (RTE) solutions.
Abstract: After more than ten years of experience with applications of fieldbus in automation technology, the industry has started to develop and adopt Real-Time Ethernet (RTE) solutions. There already exists now more than ten proposed solutions. International Electrotechnical Commission standards are trying to give a guideline and selection criteria based on recognized indicators for the user.

381 citations

Journal ArticleDOI
TL;DR: This survey provides a four step taxonomy based on smart grid domains, research goals, test platforms, and communication infrastructure to provide a taxonomy and insightful guidelines for the development as well as to identify the key features and design decisions while developing future smart grid testbeds.
Abstract: An increasing interest is emerging on the development of smart grid cyber-physical system testbeds. As new communication and information technologies emerge, innovative cyber-physical system testbeds need to leverage realistic and scalable platforms. Indeed, the interdisciplinary structure of the smart grid concept compels heterogeneous testbeds with different capabilities. There is a significant need to evaluate new concepts and vulnerabilities as opposed to counting on solely simulation studies especially using hardware-in-the-loop test platforms. In this paper, we present a comprehensive survey on cyber-physical smart grid testbeds aiming to provide a taxonomy and insightful guidelines for the development as well as to identify the key features and design decisions while developing future smart grid testbeds. First, this survey provides a four step taxonomy based on smart grid domains, research goals, test platforms, and communication infrastructure. Then, we introduce an overview with a detailed discussion and an evaluation on existing testbeds from the literature. Finally, we conclude this paper with a look on future trends and developments in cyber-physical smart grid testbed research.

322 citations