• Title/Summary/Keyword: 동적 결정 네트워크

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An Extended DDN based Self-Adaptive System (확장된 동적 결정 네트워크기반 자가적응형 시스템)

  • Kim, Misoo;Jeong, Hohyeon;Lee, Eunseok
    • Journal of KIISE
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    • v.42 no.7
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    • pp.889-900
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    • 2015
  • In order to solve problems happening in the practical environment of complicated system, the importance of the self-adaptive system has recently begun to emerge. However, since the differences between the model built at the time of system design and the practical environment can lead the system into unpredictable situations, the study into methods of dealing with it is also emerging as an important issue. In this paper, we propose a method for deciding on the adaptation time in an uncertain environment, and reflecting the real-time environment in the system's model. The proposed method calculates the Bayesian Surprise for the suitable adaptation time by comparing previous and current states, and then reflects the result following the performed policy in the design model to help in deciding the proper policy for the actual environment. The suggested method is applied to a navigation system to confirm its effectiveness.

A Self-Organization Routing Protocol for supporting Mobile Sensor Nodes (모바일 센서 노드 지원을 위한 자기구성 라우팅 프로토콜)

  • Kim Do-Seong;Chung Yeong-Jee
    • Proceedings of the Korea Information Processing Society Conference
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    • 2006.05a
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    • pp.1295-1298
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    • 2006
  • 일반적인 센서 네트워크 환경과 달리 이동성을 중시하는 환경에서의 무선 센서 네트워크는 에너지 효율성, 동적 자기구성, 이동성에 적합하도록 개발되어야 한다. 이러한 환경에서의 센서 네트워크 응용은 고정 노드와 이동 노드가 혼재되어 있는 것이 일반적이다. 본 논문에서는 이러한 이동 노드 지원을 위한 'LEACH-Mobile' 프로토콜을 제안한다. LEACH-Mobile프로토콜은 노드의 움직임에 따라 토폴로지가 변화할 때, 이동하는 노드가TDMA 스케줄에 따른 시간 슬롯에서 특정 클러스터 헤드 노드와 통신이 가능한지의 여부로서 클러스터의 멤버가 될 노드를 결정하고 클러스터를 재구성한다. LEACH-Mobile 프로토콜의 시뮬레이션 결과는 이동 노드가 증가함에 따라 이동성을 지원하지 않는 기존의 LEACH 프로토콜에 비해 데이터 전송 성공률 면에서 명확한 성능 향상을 가져오는 것을 보여준다.

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Design Integrated Model of IntServ and DiffServ Network (차등화 서비스와 종합 서비스 네트워크의 통합 모델 설계 및 성능 평가)

  • 정진우;강현국
    • Proceedings of the Korean Information Science Society Conference
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    • 2000.04a
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    • pp.274-276
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    • 2000
  • IP 망에서 서비스 품질을 제공하기 위한 기술로 RSVP 신호 프로토콜을 사용하는 종합 서비스 모델(Integrated Service Model)과 차등화 서비스(Differentiated Service)가 있다. 그러나, RSVP는 플로우별로 상태를 유지하고, 처리하기 때문에 거대한 네트워크에서는 확장성 문제가 고려되어야 한다. 반대로, 차등화 서비스는 클래스별로 처리하기 때문에 확장성 문제를 해결할 수 있지만, 완전한 형태의 서비스 품질을 보장하지 못한다는 단점을 가지고 있다. 본 논문에서는 RSVP의 장점과 차등화 서비스의 장점을 상호 결합하기 위한 통합 모델을 살펴보고, 경계 라우터의 각 모듈과 기능을 정의하였다. 또한, 차등화 서비스 영역에서 자원 예약 메시지를 최우선 서비스로 처리함으로써 동적인 자원 예약 프로토콜의 단점을 보완 하도록 하였다. 경계 라우터는 RSVP 메시지를 처리하는 RSVP 처리 모듈, RSVP의 자원 요청에 대응하는 차등화 서비스 클래스를 결정하는 서비스 매핑 처리 모듈, 마지막으로 패킷 우선순위에 따라 차별화된 서비스를 제공하는 차등화 서비스 처리 모듈로 구성되어 있다. 본 논문에서 제안한 자원 예약 메시지의 우선 처리 방법과 경계 라우터의 설계는 향후 IP 네트워크에서 쉽게 적용하고, 확장될 수 있으리라 사료된다.

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Dynamic Timeout Scheduling for Energy-Efficient Data Aggregation in Wireless Sensor Networks based on IEEE 802.15.4 (IEEE 802.15.4기반 무선센서네트워크에서 에너지 효율적인 데이터 병합을 위한 동적 타임아웃 스케줄링)

  • Baek, Jang-Woon;Nam, Young-Jin;Seo, Dae-Wha
    • Journal of KIISE:Computing Practices and Letters
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    • v.15 no.12
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    • pp.933-937
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    • 2009
  • This paper proposes a dynamic timeout scheduling for energy efficient and accurate aggregation by analyzing the single hop delay in wireless sensor networks based on IEEE 802.15.4. The proposed scheme dynamically configures the timeout value depending on both the number of nodes sharing a channel and the type of wireless media, with considering the results of delay analysis of the single hop delay. The timeout of proposed scheme is much smaller than the maximum single hop delay which is used as the timeout of traditional data aggregation schemes. Therefore the proposed scheme considerably reduces the energy consumption of idle monitoring for waiting messages. Also, the proposed scheme maintains the data accuracy by guaranteeing the reception ratio required by the sensor network applications. Extensive simulation has revealed that proposed scheme enhances energy consumption by 30% with maintaining data accuracy, as compared with the TAG data aggregation.

CACH Distributed Clustering Protocol Based on Context-aware (CACH에 의한 상황인식 기반의 분산 클러스터링 기법)

  • Mun, Chang-Min;Lee, Kang-Whan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.6
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    • pp.1222-1227
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    • 2009
  • In this paper, we proposed a new method, the CACH(Context-aware Clustering Hierarchy) algorithm in Mobile Ad-hoc Network(MANET) systems. The proposed CACH algorithm based on hybrid and clustering protocol that provide the reliable monitoring and control of a variety of environments for remote place. To improve the routing protocol in MANET, energy efficient routing protocol would be required as well as considering the mobility would be needed. The proposed analysis could help in defining the optimum depth of hierarchy architecture CACH utilize. Also, the proposed CACH could be used localized condition to enable adaptation and robustness for dynamic network topology protocol and this provide that our hierarchy to be resilient. As a result, our simulation results would show that a new method for CACH could find energy efficient depth of hierarchy of a cluster.

Utility Function-Based Scheduling in a Multi-Ship Network with Coordinated Multi-Point Transmission (협력적 다중 선박 네트워크에서 유틸리티 함수 기반의 스케줄링 기법)

  • Kim, Yunsung;Lee, Seong Ro;So, Jaewoo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.7
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    • pp.538-545
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    • 2014
  • This paper proposes a coordinated multi-point (CoMP) based dynamic transmission scheme in a downlink multi-ship network, where a central ship selects a ship in order to maximize the utility function. The proposed scheduling scheme dynamically decides to the usage of the coordinated multi transmissions and selects a user to be served for every frame, in order to the utility function on the basis of the throughput and fairness. In particular, the proposed utilify function based scheduling scheme aims to increase the quality of service of ships at the edge of cells. Under the proportional fair scheduling, the simulation results show that the proposed utility function-based scheduling improves the throughput of the ships at the cell edge with the little sacrifice of the system capacity.

High Performance QoS Multicast Routing Scheme for Real-Time Mobile Multimedia Applications in Wireless Mesh Networks (무선메쉬네트워크에서 실시간 이동 멀티미디어 응용을 위한 고성능 QoS 멀티캐스트 라우팅 기법)

  • Kang, Moonsik
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.6
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    • pp.85-94
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    • 2015
  • In this paper, an enhanced QoS multicast routing scheduling scheme is proposed to adapt to a dynamic mobile traffic condition for wireless mesh networks (WMNs). It handles the network QoS by controlling the delay constraints for multimedia applications. The group size will be controlled according to both the current network state and QoS requirements. The dynamic reconstruction of QoS multicast tree can be obtained from preprocessing with both the partial multicast routing scheme and the traffic estimation. Performance evaluation of the proposed scheme is carried out on randomly generated graph derived from the wireless mesh network, by choosing the optimal value related to the appropriate delay bounds. Simulation results show that the proposed scheme can improve the performance of QoS multicast routing for WMNs.

Regional Path Re-selection Period Determination Method for the Energy Efficient Network Management in Sensor Networks applied SEF (통계적 여과 기법이 적용된 센서 네트워크에서 에너지 효율적인 네트워크 관리를 위한 영역별 경로 재설정 주기 결정 기법)

  • Park, Hyuk;Cho, Tae-Ho
    • Journal of the Korea Society for Simulation
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    • v.20 no.3
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    • pp.69-78
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    • 2011
  • A large-scale sensor network usually operates in open and unattended environments, hence individual sensor node is vulnerable to various attacks. Therefore, malicious attackers can physically capture sensor nodes and inject false reports into the network easily through compromised nodes. These false reports are forwarded to the base station. The false report injection attack causes not only false alarms, but also the depletion of the restricted energy resources in a battery powered network. The statistical en-route filtering (SEF) mechanism was proposed to detect and drop false reports en route. In SEF, the choice of routing paths largely affect the energy consumption rate and the detecting power of the false report. To sustain the secure routing path, when and how to execute the path re-selection is greatly need by reason of the frequent network topology change and the nodes's limitations. In this paper, the regional path re-selection period determination method is proposed for efficient usage of the limited energy resource. A fuzzy logic system is exploited in order to dynamically determine the path re-selection period and compose the routing path. The simulation results show that up to 50% of the energy is saved by applying the proposed method.

A Secure Intrusion Detection System for Mobile Ad Hoc Network (모바일 Ad Hoc 네트워크를 위한 안전한 침입 탐지 시스템)

  • Shrestha, Rakesh;Lee, Sang-Duk;Choi, Dong-You;Han, Seung-Jo;Lee, Seong-Joo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.1
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    • pp.87-94
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    • 2009
  • The intrusion detection system is one of the active fields of research in wireless networks. Intrusion detection in wireless mobile Ad hoc network is challenging because the network topologies are dynamic, lack centralization and are vulnerable to attacks. Detection of malicious nodes in an open ad-hoc network in which participating nodes do not have previous security association has to face number of challenges which is described in this paper. This paper is about determining the malicious nodes under critical conditions in the mobile ad-hoc network and deals with security and vulnerabilities issues which results in the better performance and detection of the intrusion.

A Centralized QoS Routing Architecture with No Dynamic Network State Information Exchange Overhead (동적 네트워크 상태정보 교환 오버헤드를 제거한 중앙 집중적 QoS 라우팅 구조)

  • Kim, Sung-Ha;Lee, Mee-Jeong
    • Journal of KIISE:Information Networking
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    • v.29 no.5
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    • pp.573-582
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    • 2002
  • We propose centralized server based QoS routing schemes, where a route server is responsible for determining QoS paths on behalf of all the routers in a routing domain. In the proposed server based schemes, the dynamic link QoS state information, which is required for a QoS path computation, is implicitly maintained at route server as it assigns or gets back QoS paths. By maintaining the network state information this way, we may not only eliminate the overhead to exchange network state update message but also achieve higher routing performance by utilizing accurate network state information in path computation. We discuss path caching techniques for reducing the amount of path computation overhead at the route server, and evaluate the performance of the proposed schemes using simulation. The simulation results show that the path caching schemes may significantly reduce the route server load. The proposed schemes are also compared to the distributed QoS routing schemes proposed in the literature. It has been shown that the proposed server based schemes not only enhance the routing performance, but they are also competitive with respect to routing overheads.