• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권8호
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• pp.3701-3727
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• 2016

Recently Service Function Chaining (SFC) is promising to innovate the network service mode in modern networks. However, a feasible implementation of SFC is still difficult due to the need to achieve functional equivalence with traditional modes without sacrificing performance or increasing network complexity. In this paper, we present a configurable network service chaining (CNSC) mechanism to provide services for network traffics in a flexible and optimal way. Firstly, we formulate the problem of network service chaining and design an effective service chain construction framework based on integrating software-defined networking (SDN) with network functions virtualization (NFV). Then, we model the service path computation problem as an integer liner optimization problem and propose an algorithm named SPCM to cooperatively combine service function instances with a network utility maximum policy. In the procedure of SPCM, we achieve the service node mapping by defining a service capacity matrix for substrate nodes, and work out the optimal link mapping policies with segment routing. Finally, the simulation results indicate that the average request acceptance ratio and resources utilization ratio can reach above 85% and 75% by our SPCM algorithm, respectively. Upon the prototype system, it is demonstrated that CNSC outperforms other approaches and can provide flexible and scalable network services.

• 한국정밀공학회지
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• 제22권4호
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• pp.136-143
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• 2005

Open architecture controller (OAC) is well known technology in factory automation. To better understand the requirements of OAC, authors have discussed the OAC related topics with a number of control experts who represents different segments of the machining industry. There is no common concept that is accepted or used, however, the common ideas for OAC is the control system that is hardware independent, interchangeable, and easily scalable. This paper presents summary of the understaning and requirements of OAC. Based on the requirements of OAC, authors developed the software based PC-CNC. The main focus of the PC-CNC was on the user customization capability and open interface between control networks in manufacturing system. This paper introduces the developed PC-CNC briefly. In addition to introduction of the PC-CNC, to fill the gap between end users and vendors of OAC, this paper presents two applications using OAC. One is a remote monitoring system. The OPC (Ole for Process Control) standard interface was used to monitor the status of open architecture CNC across network. The other is the remote production management module for machine tools using standard database interface.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권4호
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• pp.1479-1501
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• 2020

Dependable functioning of dynamic networks is essential for delivering ubiquitous services. Faults are the root causes of network outages. The comparison diagnosis model, which automates fault's identification, is one of the leading approaches to attain network dependability. Most of the existing research has focused on stationary networks. Nonetheless, the time-free comparison model imposes no time constraints on the system under considerations, and it suits most of the diagnosis requirements of dynamic networks. This paper presents a novel protocol that diagnoses faulty nodes in diagnosable dynamic networks. The proposed protocol comprises two stages, a testing stage, which uses the time-free comparison model to diagnose faulty neighbour nodes, and a disseminating stage, which leverages a Random Linear Network Coding (RLNC) technique to disseminate the partial view of nodes. We analysed and evaluated the performance of the proposed protocol under various scenarios, considering two metrics: communication overhead and diagnosis time. The simulation results revealed that the proposed protocol diagnoses different types of faults in dynamic networks. Compared with most related protocols, our proposed protocol has very low communication overhead and diagnosis time. These results demonstrated that the proposed protocol is energy-efficient, scalable, and robust.

• International Journal of Internet, Broadcasting and Communication
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• 제8권1호
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• pp.33-41
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• 2016

Big data management is becoming an increasingly important issue in both industry and academia of information science community today. One of the important categories of big data generated from software systems is log data. Log data is generally used for better services in various service providers and can also be used to improve system reliability. In this paper, we propose a novel big data management architecture specialized for log data. The proposed architecture provides a scalable log management system that consists of client and server side modules for efficient handling of log data. To support large and simultaneous log data from multiple clients, we adopt the Hadoop infrastructure in the server-side file system for storing and managing log data efficiently. We implement the proposed architecture to support various client environments and validate the efficiency through measurement studies. The results show that the proposed architecture performs better than the existing logging architecture by 42.8% on average. All components of the proposed architecture are implemented based on open source software and the developed prototypes are now publicly available.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.3-9
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• 2008

Recently, the plant industries are being activated and plant control systems use various technologies. Because the optimized design for the plants is very important for the reducing of operation and maintenance costs, automatic control systems become more important. Plant control systems consist of the master controller, the plant networks, the programming environment for engineering, monitoring software and the field devices. The control systems should have reliability, availability and safety. Modular architecture of hardware and software makes flexible configuration of the control systems. Each component should have diagnostic functions. It follows industrial standards and makes open systems. Open systems increase accessibility against the data which is distributed in the plants. The controllers including processor and communication modules use the up-to-date technology. They have real time and fault tolerant function by duplicating processors or networks. It also enables to make the distributed control systems. The distributed architecture makes more scalable main control system. Automatic control systems can be operated with better performance. In this paper, we analyzed the requirements of the seawater desalination plants and made some consideration facts for developing the optimized controller. Also we described the design concept of the main controller, which consists of several modules. We should validate and complement the design for the reliability and better performance.

• Journal of Information Processing Systems
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• 제6권4호
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• pp.481-500
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• 2010

The Internet explosion and the increase in crucial web applications such as ebanking and e-commerce, make essential the need for network security tools. One of such tools is an Intrusion detection system which can be classified based on detection approachs as being signature-based or anomaly-based. Even though intrusion detection systems are well defined, their cooperation with each other to detect attacks needs to be addressed. Consequently, a new architecture that allows them to cooperate in detecting attacks is proposed. The architecture uses Software Agents to provide scalability and distributability. It works in two modes: learning and detection. During learning mode, it generates a profile for each individual system using a fuzzy data mining algorithm. During detection mode, each system uses the FuzzyJess to match network traffic against its profile. The architecture was tested against a standard data set produced by MIT's Lincoln Laboratory and the primary results show its efficiency and capability to detect attacks. Finally, two new methods, the memory-window and memoryless-window, were developed for extracting useful parameters from raw packets. The parameters are used as detection metrics.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권8호
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• pp.3904-3917
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• 2017

IP multimedia subsystem (IMS) is an open standardized architecture for delivering multimedia service over IP network in a route-agnostic manner. With the increasing popularity of conversational class service, the delivery of a traffic flow with a certain bandwidth demand over a single network path is either not possible or not cost-effective. Multipath transmission is considered to be a promising solution to provide high-quality delivery service. This paper proposes a software defined service overlay network (SDSON) based multipath transmission framework for IMS, which is complementary to existing network architecture. The framework transforms original two-party session negotiation into three-party session negotiation that supports participants to negotiate multipath transmission capacity and path information by signaling message. Based on existing IETF standards, SIP and SDP are scalable to support these functions. Finally, the proposed framework is fully implemented on open source platform and examined by experiments. Experimental results show that multipath-enabled IMS is an effective way to improve the delivery performance of conversational class service.

• 한국정보처리학회논문지
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• 제7권9호
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• pp.2815-2826
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• 2000

본 논문은 ATM교환 시스템과 같은 실시간 분산 소프트웨어를 범용 컴퓨터 시스템에서 실행할 수 있는 환경을 제공하는 CHILL 실행시간 지원 시스템(CHILL, Run-time System)의 설계 및 구현 기술에 관하여 기술한다. 이를 위하여 실시간 분산 CHILL 프로그램을 위한 실행 모델을 제시하고 해당 실행 모델을 갖는 소프트웨어를 범용 컴퓨터에서 실행하는 CRS를 개발하였다. CRS는 목적 시스템 운영체제와 동일한 실행환경을 호스트 컴퓨터에서 제공함으로 프로그래머는 목적 시스템이 없이도 소프트웨어 개발이 가능하다. 또한 다수의 개발자가 동시에 소프트웨어를 실행할 수 있는 환경을 제공하여 프로그램 생산성 향상에 도움이 된다. 이 실행환경은 SROS(Scalable Real-time Operating System)를 위하여 개발되었지만 다른 내장형 운영체제의 실행환경으로 확장이 용이하다.

• Smart Structures and Systems
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• 제6권5_6호
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• pp.423-438
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• 2010

Wireless smart sensors enable new approaches to improve structural health monitoring (SHM) practices through the use of distributed data processing. Such an approach is scalable to the large number of sensor nodes required for high-fidelity modal analysis and damage detection. While much of the technology associated with smart sensors has been available for nearly a decade, there have been limited numbers of fulls-cale implementations due to the lack of critical hardware and software elements. This research develops a flexible wireless smart sensor framework for full-scale, autonomous SHM that integrates the necessary software and hardware while addressing key implementation requirements. The Imote2 smart sensor platform is employed, providing the computation and communication resources that support demanding sensor network applications such as SHM of civil infrastructure. A multi-metric Imote2 sensor board with onboard signal processing specifically designed for SHM applications has been designed and validated. The framework software is based on a service-oriented architecture that is modular, reusable and extensible, thus allowing engineers to more readily realize the potential of smart sensor technology. Flexible network management software combines a sleep/wake cycle for enhanced power efficiency with threshold detection for triggering network wide operations such as synchronized sensing or decentralized modal analysis. The framework developed in this research has been validated on a full-scale a cable-stayed bridge in South Korea.

• Asian Journal of Innovation and Policy
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• 제4권3호
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• pp.271-287
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• 2015

Universities are now operating in a post-globalized world. They need to be locally engaged while globally visible for continued success. Specific strategies include 1) unbundling education using fractal modules approach to facilitate more flexible and customized learning expectations of net generation of students; 2) open-source software and hardware platforms to facilitate collaborations around a short or multi-year, multidisciplinary brain stretching projects motivated by the real world challenges; 3) new courses on innovation and entrepreneurship to nurture experience seeking and enterprising mindset of students; 4) cross-border university- public- private partnerships for developing solutions specific to the local needs and can be scalable for the world; and 5) encouraging faculty members with glocal mindset.