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An effective method for service components selection based on micro-canonical annealing considering dependability assurance

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Frontiers of Computer Science 2019年第2期13卷 264-279页

作者： Shichen ZOU Junyu LIN Huiqiang WANG Hongwu LV Guangsheng FENG College of Computer Science and Technology Harbin Engineering University Harbin 150001 China Institute of Information Engineering Chinese Academy of Sciences Beijing 100093 China Department of Electrical and Computer Engineering University of Victoria Victoria V8W 3P6 Canada

Distributed virtualization changes the pattern of building software systems. However, it brings some problems on dependability assurance owing to the complex social relationships and interactions between service components. The best way to solve the problems in a distributed virtualized environment is dependable service components selection. Dependable service components selection can be modeled as finding a dependable service path, which is a multiconstrained optimal path problem. In this paper, a service components selection method that searches for the dependable service path in a distributed virtualized environment is proposed from the perspective of dependability assurance. The concept of Quality of dependability is introduced to describe and constrain software system dependability during dynamic composition. Then, we model the dependable service components selection as a multiconstrained optimal path problem, and apply the Adaptive Bonus-Penalty Microcanonical Annealing algorithm to find the optimal dependable service path. The experimental results show that the proposed algorithm has high search success rate and quick converges.

关键词： service components selection dependability assurance distributed virtualization microcanonical annealing

Mercury: Combining Performance with dependability Using Self-Virtualization

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Journal of Computer Science & Technology 2012年第1期27卷 92-104页

作者：陈海波张逢喆陈榕臧斌宇游本中 School of Software Shanghai Jiaotong UniversityShanghai 200240China Parallel Processing Institute Fudan UniversityShanghai 201203China Institute of Information Science Academia SinicaTaipeiChina

Virtualization has recently gained popularity largely due to its promise in increasing utilization, improving availability and enhancing security. Very often, the role of computer systems needs to change as the business environment changes. Initially, the system may only need to host one operating system and seek full execution speed. Later, it may be required to add other functionalities such as allowing easy software/hardware maintenance, surviving system failures and hosting multiple operating systems. Virtualization allows these functionalities to be supported easily and effectively. However, virtualization techniques generally incur non-negligible performance penalty. Fortunately, many virtualization- enabled features such as online software/hardware maintenance and fault tolerance do not require virtualization standby all the time. Based on this observation, this paper proposes a technique, called Self-virtualization, which provides the operating system with the capability to turn on and off virtualization on demand, without disturbing running applications. This technique enables computer systems to reap most benefits from virtualization without sacrificing performance. This paper presents the design and implementation of Mercury, a working prototype based on Linux and Xen virtual machine monitor. The performance measurement shows that Mercury incurs very little overhead： about 0.2 ms on 3 GHz Xeon CPU to complete a mode switch, and negligible performance degradation compared to Linux.

关键词： dependability performance self-virtualization dynamic virtualization

A survey on dependability improvement techniques for pervasive computing systems

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Science China(Information Sciences) 2015年第5期58卷 19-32页

作者： YANG WenHua LIU YePang XU Chang CHEUNG S.C. State Key Laboratory for Novel Software Technology Nanjing University Department of Computer Science and Technology Nanjing University Department of Computer Science and Engineering The Hong Kong University of Science and Technology

The goal of this survey is to summarize the state-of-the-art research results and identify research challenges of developing and deploying dependable pervasive computing systems. We discuss the factors that affect the system dependability and the studies conducted to improve it with respect to these factors. These studies were categorized according to their similarities and differences in hope of shedding some insight into future research. There are three categories: context management, fault detection, and uncertainty handling.These three categories of work address the three most difficult problems of pervasive computing systems. First,pervasive computing systems’ perceived environments, which are also called their contexts, can vary intensively,and thus have a great impact on the systems’ dependability. Second, it is challenging to guarantee the correctness of the systems’ internal computations integrated with interactions with external environments for developers.Fault detection is then an important issue for improving dependability for these systems. Last but not least importantly, pervasive computing systems interact with their environments frequently. These interactions can be affected by many uncertainties, which can jeopardize the systems’ dependability. After a discussion of these pieces of work, we present an outlook for its future research directions.

关键词： pervasive computing system dependability context fault detection uncertainty

Electricity Services Based dependability Model of Power Grid Communication Networking

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Tsinghua Science and Technology 2014年第2期19卷 121-132页

作者： Jiye Wang Kun Meng Junwei Cao Zhen Chen Lingchao Gao Chuang Lin Department of Information and Communication State Grid the Computer School Beijing Information Science and Technology University Department of Computer Science and Technology Tsinghua University the Research Institute of Information Technology Tsinghua National Laboratory for Information Science and TechnologyTsinghua University

The technology of Ultra-High Voltage （UHV） transmission requires higher dependability for electric power grid. Power Grid Communication Networking （PGCN）, the fundamental information infrastructure, severs data transmission including control signal, protection signal, and common data services. dependability is the necessary requirement to ensure services timely and accurately. dependability analysis aims to predicate operation status and provide suitable strategies getting rid of the potential dangers. Due to the dependability of PGCN may be affected by external environment, devices quality, implementation strategies, and so on, the scale explosion and the structure complexity make the PGCN＇s dependability much challenging. In this paper, with the observation of interdependency between power grid and PGCN, we propose an electricity services based dependability analysis model of PGCN. The model includes methods of analyzing its dependability and procedures of designing the dependable strategies. We respectively discuss the deterministic analysis method based on matrix analysis and stochastic analysis model based on stochastic Petri nets.

关键词： power grid communication networking dependability stochastic Petri nets strategy design

Eliciting dependability requirements:a control cases based approach

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Science China(Information Sciences) 2014年第1期57卷 96-110页

作者： LIU Chun WANG Yue ZHANG Wei JIN Zhi Academy of Mathematics and System Science Chinese Academy of Sciences Key Laboratory of High Confidence Software Technologies (Peking University) Ministry of Education Institute of Software School of Electronics Engineering and Computer Science Peking University

At present,great demands are posed on software dependability.But how to elicit the dependability requirements is still a challenging task.This paper proposes a novel approach to address this issue.The essential idea is to model a dependable software system as a feedforward-feedback control system,and presents the use cases+control cases model to express the requirements of the dependable software systems.In this model,while the use cases are adopted to model the functional requirements,two kinds of control cases(namely the feedforward control cases and the feedback control cases)are designed to model the dependability requirements.The use cases+control cases model provides a unified framework to integrate the modeling of the functional requirements and the dependability requirements at a high abstract level.To guide the elicitation of the dependability requirements,a HAZOP based process is also designed.A case study is conducted to illustrate the feasibility of the proposed approach.

关键词： dependability dependability requirements requirements elicitation control systems control cases

On　dependability　of　Computing　Systems

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Journal of Computer Science & Technology 1999年第2期14卷 116-128页

作者：徐拾义 Department of Computer Science Shanghai University Shanghai P.R. China

With the rapid development and wide applicatioos of computing systems on which more reliance hu been put, a dependable syatem will be much more important than ever. This paper is hrst aimed at giving informal but precise definitions characterizing the various attributes of dependability of computing sys- tems and then the importance of (and the relationshipa among) all the attributes are explained . dependability is first introduced as a global concept which subsumes the usual attributea of reliability, availabilityt maintainability, safety and securit. The basic definitions given bere are then commended and supplemented by detailed material and additional explanations in the subsequent sections . The presentation has been structured as follows so as to attract the reader's atteation to the important attributions of dependability. Search for a few number of concise concepts enabling the dependability at- tributes to be expressed as clearly as possible. Use of terms which are identical or as close as possible to those commonly used mowadays . This paper is also intended to provoke people's interest in designing a dependable computing system.

关键词： dependability reliability availability safety security

A dependability Model for TMR System

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International Journal of Automation and computing 2012年第3期9卷 315-324页

作者： Peng, Jun-Jie Liu, Yan-Ping Chen, Yuan-Yuan School of Computer Engineering and Science Shanghai University Shanghai 200072 China Key Laboratory of Computer System and Architecture Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China

Much research has been done on the dependability evaluation of computer systems. However, much of this is gone no further than study of the fault coverage of such systems, with little focus on the relationship between fault coverage and overall system dependability. In this paper, a Markovian dependability model for triple-modular-redundancy (TMR) system is presented. Having fully considered the effects of fault coverage, working time, and constant failure rate of single module on the dependability of the target TMR system, the model is built based on the stepwise degradation strategy. Through the model, the relationship between the fault coverage and the dependability of the system is determined. What is more, the dependability of the system can be dynamically and precisely predicted at any given time with the fault coverage set. This will be of much benefit for the dependability evaluation and improvement, and be helpful for the system design and maintenance.

关键词： dependability Markovian model coverage triple-modular-redundancy (TMR) failure rate.

Performance evaluation of IoT-based service system for monitoring nutritional deficiencies in plants

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农业信息处理(英文) 2023年第1期10卷 52-70页

作者： Heri Andrianto Suhardi Ahmad Faizal Novianto Budi Kurniawan Dimas Praja Purwa Aji School of Electrical Engineering and Informatics Institut Teknologi BandungBandung 40132Indonesia School of Life Sciences and Technology Institut Teknologi BandungBandung 40132Indonesia Directorate of Statistical Information System Statistics of IndonesiaJakarta 10710Indonesia

This study aimed to develop and evaluate the performance of a service system platform based on the Internet of Things(IoT)for monitoring nutritional deficiencies in plants and providing fertilizer recommendations.There are two distinct differences between this work and previous ones;namely,this service system platform has been developed based on IoT using a system engineering approach and its performance has been evaluated using dependability.We have successfully developed and integrated a service system platform and chlorophyll meter that is based on IoT.We have also successfully tested the performance of the service system platform using the JMeter software.The dependability value measured from the five tested variables(reliability,availability,integrity,maintainability,and safety)showed a value of 0.97 which represents a very good level of system confidence in not failing to deliver services to users under normal operational conditions.From a future perspective,this platform can be used as an alternative service to monitor nutrient deficiencies in plants and provide fertilization recommendations to increase yields,reduce fertilizer costs,and prevent the use of excessive fertilizers,which can cause environmental pollution.

关键词： dependability Fertilization recommendation Internet of Things Nutritional deficiencies Service system platform System engineering

On the dependability of Highly Heterogeneous and Open Distributed Systems

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Journal of Software Engineering and Applications 2018年第1期11卷 28-68页

作者： Naftaly H. Minsky Department of Computer Science Rutgers University New Brunswick NJ USA

This paper introduces an architecture of distributed systems that facilitates the implementation of a substantial range of dependable system properties, i.e., properties that span an entire system, or a set of components dispersed throughout it. This architecture, called GDS, for governed distributed system, governs the system by controlling the flow of messages between its actors, independently of the internals of the interacting actors. This governance is done via an enforced collection of interaction laws organized into a modular and conflict free hierarchical ensemble. This ensemble of laws is sensitive to the history of interaction;and it is enforced in a decentralized manner, and is thus scalable. The dependable system properties that can be implemented under GDS can have the following beneficial consequences, among others: a) the ability to establish regularities over the system, rendering it more coherent, and easier to reason about;b) the ability to provide a degree of trust among the disparate actor of the system;and c) the ability to ensure compliance with interaction protocols that are essential for distributed computing. Consequently, the GDS architecture can have a significant impact on the following important system qualities: security, fault tolerance, auditability, and manageability.

关键词： Open Distributed Systems Governance dependability System Properties Middleware LGI Fault Tolerance Security