• Title/Summary/Keyword: Network Blocking

검색결과 347건 처리시간 0.021초

Performance Analysis of an Adaptive Link Status Update Scheme Based on Link-Usage Statistics for QoS Routing

  • Yang, Mi-Jeong;Kim, Tae-Il;Jung, Hae-Won;Jung, Myoung-Hee;Choi, Seung-Hyuk;Chung, Min-Young;Park, Jae-Hyung
    • ETRI Journal
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    • 제28권6호
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    • pp.815-818
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    • 2006
  • In the global Internet, a constraint-based routing algorithm performs the function of selecting a routing path while satisfying some given constraints rather than selecting the shortest path based on physical topology. It is necessary for constraint-based routing to disseminate and update link state information. The triggering policy of link state updates significantly affects the volume of update traffic and the quality of services (QoS). In this letter, we propose an adaptive triggering policy based on link-usage statistics in order to reduce the volume of link state update traffic without deterioration of QoS. Also, we evaluate the performance of the proposed policy via simulations.

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Fuzzy Logic Based Neural Network Models for Load Balancing in Wireless Networks

  • Wang, Yao-Tien;Hung, Kuo-Ming
    • Journal of Communications and Networks
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    • 제10권1호
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    • pp.38-43
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    • 2008
  • In this paper, adaptive channel borrowing approach fuzzy neural networks for load balancing (ACB-FNN) is presented to maximized the number of served calls and the depending on asymmetries traffic load problem. In a wireless network, the call's arrival rate, the call duration and the communication overhead between the base station and the mobile switch center are vague and uncertain. A new load balancing algorithm with cell involved negotiation is also presented in this paper. The ACB-FNN exhibits better learning abilities, optimization abilities, robustness, and fault-tolerant capability thus yielding better performance compared with other algorithms. It aims to efficiently satisfy their diverse quality-of-service (QoS) requirements. The results show that our algorithm has lower blocking rate, lower dropping rate, less update overhead, and shorter channel acquisition delay than previous methods.

ATM망에서 SRBTD을 이용한 경로선택 및 복구 처리방안 (A Method of Virtual Path Selection and Restoration Using SRBTD on the ATM Network)

  • 김형철;홍충선;이대영;곽윤식
    • 한국통신학회논문지
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    • 제24권12A호
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    • pp.1917-1921
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    • 1999
  • 본 논문은 기존의 방법론에서 발생되는 경로들의 편중현상과 이에 따른 블록킹 확률이 증대되는 문제를 완화시키고 자원의 사용 효율성을 확대하여 망의 신뢰성과 효율성을 높이기 위한 경로분산 방법론을 연구하였다. 즉, 경로계산 시 링크점유율을 고려한 경로계산식으로 임의의 링크에 트래픽이 집중되는 것을 막을 수 있는 보다 효과적인 경로계산법을 제안하였다. 또한 발생할 수 있는 연결장애에 대해 효과적으로 대응하여 빠르게 연결설정하는 방안에 대해 연구하였다.

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Network CCTV 환경에서 악의적인 사용자를 차단하기 위한 RTSP 사용자 인증 프로토콜 (RTSP User Authentication Protocol for Blocking Malicious User in Network CCTV Environment)

  • 박태성;강도운;전문석
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2011년도 춘계학술논문집 1부
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    • pp.239-242
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    • 2011
  • 기존 CCTV는 대부분 방범을 목적으로 많이 쓰인다. 이러한 CCTV는 과거엔 대부분 아날로그 방식이었으나 CCTV에 IP를 부여하고 Network화가 되면서 CCTV가 웹상의 위협에 노출이 되었다. CCTV영상이란 사생활 관련 영상이며 이러한 영상이 불특정 다수에 노출되어 있다는 건 충분히 민감한 문제라 할 수 있다. 본 논문에서는 CCTV의 네트워크화로 인해 발생한 취약점을 분석 및 보안하였다. 또한 CCTV영상 유출을 미연에 방지하기 위한 RTSP 사용자 인증 프로토콜을 제안한다.

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Parallel 3-dimensional optical interconnections using liquid crystal devices for B-ISDN electronic switching systems

  • Jeon, Ho-In;Cho, Doo-Jin
    • Journal of the Optical Society of Korea
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    • 제1권1호
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    • pp.52-59
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    • 1997
  • In this paper, we propose a system design for a parallel3-dimensional optical interconnection network utilizing variable grating mode liquid crystal devices (VGM LCD's) which are optical transducers capable of performing intensity-to-spatial-frequency conversion. The proposed system performs real-time, reconfigurable, but blocking and nonbroadcasting 3-dimensional optical interconnections. The operating principles of the 3-D optical interconnection network are described, and some of the fundamental limitations are addressed. The system presented in this paper can be directly used as a configuration of switching elements for the 2-D optical perfect-shuffle dynamic interconnection network, as well as for a B-ISDN photonic switching system.

ATM에 적합한 banyan 스위치 소자의 성능 개선에 관한 연구 (A study on performance improvement of switch element inbanyan network for ATM)

  • 조해성;김남희;이상태;정진태;전병실
    • 한국통신학회논문지
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    • 제21권7호
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    • pp.1756-1764
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    • 1996
  • 본 눈문에서는 buffered Banyan 네트워크에 적용되는 스위치 소자의 성능을 향상시키는 방안을 제안하고 제안된 스위치 소자의 성능을 측정하여 성능이 향상됨을 보였다. 기존의 buffered Banyan 네트워크의 스위치 소자에 FIFO(First In First Out) 버퍼를 채용하므로서 HOL(Heda-Of-Line) 블로킹이 발생하여 네트워크의 성능을 저하시킨다. 제안된 스위치 소자는 기본정보 이외의 보조정보를 이용하여 버퍼를 관리하는 CASO(Contents ASsociated Output)버퍼를 채용하므로서 HOL(Head-Of-Line) 블로킹의 발생을 제거하여 네트워크의 성능을 향상시켰다. 또한 성능측정을 위하여 buffered Banyan 네트워크의 해석모델인 MY 모델에 근거하여 제안된 네트워크를 해석하였고 이 관계식들을 이용하여 성능을 측정하였다.

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The Forwarding Channel of a BTS in IS-95 CDMA Cellular Network

  • Kwag, Min-kok;Jung, Duk-in;Shin, In-Cheol
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 ITC-CSCC -2
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    • pp.990-994
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    • 2000
  • The design of LAI(Local Area Identifier), the first paging area for searching the mobile terminal has a close relation with the performance of paging channel in CDMA cellular network. This paper discusses the performance of the forward channel of IS-95 CDMA standard, known as the paging through the related messages such as call control message, channel assignment message. Modeling and simulation work were conducted to quantify the performance of paging channel in terms of traffic handling capacity and blocking levels. This result serves as illustrative guidelines for the proper engineering of common control channel, which has a major impact on the overall performance of cellular network.

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광 가상사설망에서 우선순위기반 최소간섭 경로 멀티캐스트 라우팅 알고리즘 연구 (Priority-based Minimum Interference Path Multicast RWA Algorithm in Optical Virtual Private Network)

  • 서상보;송승미;이종근;김성운
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2007년도 하계종합학술대회 논문집
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    • pp.11-12
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    • 2007
  • OVPN(Optical Virtual Private Network) based on DWDM(Dense Wavelength Division Multiplexing) backbone framework is considered as a promising approach for the future VPN. This paper proposes a new routing algorithm, called PMIPMR (Priority-based Minium Interference Path Multicast Routing) algorithm which finds an alternate route considering node priorities when the congestion is occurred in a network. The PMIPMR algorithm tries to improve blocking probability and wavelength utilization by avoiding congested path for potential future connection requests.

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Dynamic Routing and Spectrum Allocation with Traffic Differentiation to Reduce Fragmentation in Multifiber Elastic Optical Networks

  • ZOUNEME, Boris Stephane;ADEPO, Joel;DIEDIE, Herve Gokou;OUMTANAGA, Souleymane
    • International Journal of Computer Science & Network Security
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    • 제21권3호
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    • pp.1-10
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    • 2021
  • In recent decades, the heterogeneous and dynamic behavior of Internet traffic has placed new demands on the adaptive resource allocation of the optical network infrastructure. However, the advent of multifiber elastic optical networks has led to a higher degree of spectrum fragmentation than conventional flexible grid networks due to the dynamic and random establishment and removal of optical connections. In this paper, we propose heuristic routing and dynamic slot allocation algorithms to minimize spectrum fragmentation and reduce the probability of blocking future connection requests by considering the power consumption in elastic multifiber elastic optical networks.

Markov Chain based Packet Scheduling in Wireless Heterogeneous Networks

  • Mansouri, Wahida Ali;Othman, Salwa Hamda;Asklany, Somia
    • International Journal of Computer Science & Network Security
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    • 제22권3호
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    • pp.1-8
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    • 2022
  • Supporting real-time flows with delay and throughput constraints is an important challenge for future wireless networks. In this paper, we develop an optimal scheduling scheme to optimally choose the packets to transmit. The optimal transmission strategy is based on an observable Markov decision process. The novelty of the work focuses on a priority-based probabilistic packet scheduling strategy for efficient packet transmission. This helps in providing guaranteed services to real time traffic in Heterogeneous Wireless Networks. The proposed scheduling mechanism is able to optimize the desired performance. The proposed scheduler improves the overall end-to-end delay, decreases the packet loss ratio, and reduces blocking probability even in the case of congested network.