MPLS 망에서 차별화 된 서비스를 제공하기 위한 빠른 Multipoint-to-Point LSP 결정 방식

김성관,조영종,Kim, Seong-Gwan,Jo, Yeong-Jong 대한전자공학회 2002 電子工學會論文誌-TC (Telecommunications) Vol.39 No.5

MPLS(Multiprotocol Label Switching) 망에서 LSP(Lable Switched Path)의 수와 레이블 수를 줄이는 것은 망의 자원 관리 측면에서 매우 중요하며, MTP(Multipoint-to-Point) LSP는 이러한 문제점을 해결할 수 있다. 트래픽 엔지니어링을 고려할 때, MTP LSP는 트래픽 부하의 균형을 통한 망의 가용성과 링크 사용율을 높이는 경로를 선택하여야 한다. 또한 링크 단절시의 재 경로 설정이 요구되므로 빠른 경로 결정 방법이 요구된다. 본 논문은 Diffserv를 지원하는 MPLS 망에서, Diffserv의 PHB(Per Hop Behavior)와 다중경로 MTP LSP간의 매핑을 통한 트래픽 엔지니어링을 제안한다. 제안하는 트래픽 엔지니어링은 서비스 특성에 따라 계층적인 MTP LSP의 다중 경로를 결정한다. Monte-Carlo 방법을 사용한 빠른 트래픽 부하 균형 해를 구함으로써, 망 형태 정보가 빈번히 변하는 대규모 망에서 신속한 재 경로 결정을 할 수 있다. 제안하는 MTP LSP의 경로 결정 방법은 알고리즘의 수행 정도에 따라 최적의 경로 결정에 접근한다. 경로 결정의 시간 복잡도는 O(Cn²logn)으로 기존의 다중 경로 결정 방법과 동일한 시간 복잡도를 가지며, 선형 프로그래밍 접근보다 빠른 수행 시간을 갖는다. 시뮬레이션 결과 제안하는 알고리즘은 망의 형태정보와 요구하는 트래픽 부하 균형에 따라 효과적으로 제어될 수 있음을 보이며, 또한 제안하는 트래픽 엔지니어링의 호 차단율과 대역폭 차단율을 비교함으로써 망의 가용성이 기존의 다중경로 설정보다 높음을 보인다. In a MPLS(Multiprotocol Label Switching) network, it is important to reduce the number of labels and LSP(Lable Switched Path)s for network resource management. MTP(Multipoint-to-Point) LSP can be used to solve this problem. In consideration of traffic engineering, MTP LSP must be chosen to enhance the availability of network and link utilization. Also, a fast mechanism to setup MTP LSPs is required for rerouting capability against link failure. In this paper, we propose a fast MTP LSP traffic engineering of multipath MTP LSP by using a mapping of a MTP LSP upon Diffserv PHBs(Per Hop Behavior) in a Diffserv-capable MPLS network. In the proposed traffic engineering, we determine multiple MTP LSPs in a hierarchical manner according to the characteristics of different services. By using Monte-Carlo method for traffic load balancing process, it provides fast rerouting capability in case of frequent link failure across large network. Out method produces to be nearly optimal within reasonable run-times. It's time complexity is in O( Cn$^2$logn) as conventional multipath routing and it is much faster than Linear Programming approach. Simulation results show that the proposed traffic engineering can be controlled effectively in an administrative manner and enhance the availability of network in comparison with conventional multipath routing.

Design and performance evaluation of a 156-Mb/s point-to-multipoint millimeter-wave fiber-radio access link

Choi, Sung Tae,Yang, Ki Seok,Nishi, Seiji,Shimizu, Satoru,Tokuda, Kiyohito,Kim, Yong Hoon Wiley Subscription Services, Inc., A Wiley Company 2006 MICROWAVE AND OPTICAL TECHNOLOGY LETTERS Vol.48 No.6

<P>A 60-GHz point-to-multipoint (P-MP) fiber-radio access link with data rate of 156 Mb/s is presented. For a compact system configuration, a small-size 60-GHz transceiver module with planar antennas is developed. A point-to-point (P-P) full-duplex fiber-optic configuration is extended to the scheme with multiple access points (APs) by using a tree coupler and a dense wavelength-division multiplexing (DWDM) multiplexer (MUX). The bit error rate (BER) performances of the 60-GHz fiber-radio access link are measured and compared. Furthermore, the effect of the extension to the scheme with multiple APs is evaluated. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1219–1222, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21576</P>

Protection Switching Methods for Point-to-Multipoint Connections in Packet Transport Networks

김대업,류정동,이종현,김병철,이재용 한국전자통신연구원 2016 ETRI Journal Vol.38 No.1

In this paper, we discuss the issues of providing protection for point-to-multipoint connections in both Ethernet and MPLS-TP-based packet transport networks. We introduce two types of per-leaf protection—linear and ring. Neither of the two types requires that modifications to existing standards be made. Their performances can be improved by a collective signal fail mechanism proposed in this paper. In addition, two schemes—tree protection and hybrid protection—are newly proposed to reduce the service recovery time when a single failure leads to multiple signal fail events, which in turn places a significant amount of processing burden upon a root node. The behavior of the tree protection protocol is designed with minimal modifications to existing standards. The hybrid protection scheme is devised to maximize the benefits of per-leaf protection and tree protection. To observe how well each scheme achieves an efficient traffic recovery, we evaluate their performances using a test bed as well as computer simulation based on the formulae found in this paper.

Traditional Software Development for WLAN Propagation Model

Ibrahim Anwar Hassan,Ismail Mahamod,Jumari Kasmiran,Kiong Tiong Sieh The Korean Institute of Electrical Engineers 2007 Journal of Electrical Engineering & Technology Vol.2 No.1

SPWPM traditional software development is surveyed and essential problems are investigated on the basis of system wireless link considerations. This paper presents the current state software planning tools for wireless LAN link optimization. The software directory is based on combination of MatLab and MapInfo software and measurement which gives the best grouping parameters to build up the software development. Among the requirements assumed, the WLAN site selections must be Line-of-sight (LOS) or near line of sight (NLOS) field strength prediction for either point to point or point to multi points. The results obtainable the out put of the program include two-dimensional (2D) and three dimensional (3D) plots for creating the link; design parameters through GUI representing the height and location for each antenna is depending on K-factor of the area and transmit antenna location.

Traditional Software Development for WLAN Propagation Model

Anwar Hassan Ibrahim,Mahamod Ismail,Kasmiran Jumari,Tiong Sieh Kiong 대한전기학회 2007 Journal of Electrical Engineering & Technology Vol.2 No.1

SPWPM traditional software development is surveyed and essential problems are investigated on the basis of system wireless link considerations. This paper presents the current state software planning tools for wireless LAN link optimization. The software directory is based on combination of MatLab and MapInfo software and measurement which gives the best grouping parameters to build up the software development. Among the requirements assumed, the WLAN site selections must be Line-of-sight (LOS) or near line of sight (NLOS) field strength prediction for either point to point or point to multi points. The results obtainable the out put of the program include two-dimensional (2D) and three dimensional (3D) plots for creating the link; design parameters through GUI representing the height and location for each antenna is depending on K-factor of the area and transmit antenna location.

HAPS 지상국에서 P-MP FWA 시스템으로의 간섭 영향 분석

함형일,강영흥,Ham Hyung-Il,Kang Young-Heung 한국전자파학회 2006 한국전자파학회논문지 Vol.17 No.2

본 논문에서는 새로운 간섭 모델, 실제적인 HAPS(High Altitude Platform Station) 간섭 시나리오, HAPS 시스템과 FWA(Fixed Wireless Access) 시스템에 대한 안테나 패턴, 송신 전력 등과 같은 파라미터들을 이용하여 HAPS 시스템의 지상국(GS: Ground Station)으로부터 P-MP(Point-to-Multipoint) FWA 기지국(BS: Base Station)로의 간섭 및 HAPS 시스템의 GS로부터 FWA 단말국(TS: Terminal Station)으로의 간섭 영향에 대하여 분석하였다. 분석 결과를 보게 되면, HAPS GS로부터 P-MP FWA BS로의 간섭의 경우, 섹터화된 안테나를 사용하는 BS국이 nadir (HAPS 커버리지 중심)의 반대편을 바라보고 있을 때에 두 시스템은 효율적으로 운용될 수가 있다. 그러나 HAPS GS로부터 P-MP FWA TS로의 간섭의 경우에서는 충분한 이격거리가 보장되지 않거나, 간섭 경감 기법을 사용하지 않는다면 이 대역에서 두 시스템은 효율적인 스펙트럼 공유가 불가능하다. In this paper, we have analyzed the effects of interference from HAPS ground stations to P-MP FWA base station and to P-MP FWA terminal station using more detail parameters such as a new interference model, a realistic HAPS scenario, practical antenna patterns for both the HAPS system and FWA systems. The analysis results show that, in the case of interference from HAPS GSs into a P-MP BS, compatibility of the two systems can be obtained by using a sectored BS antenna with the boresight directed away from the nadir. However, in the case of interference from HAPS GSs into a P-MP TS, the two systems cannot operate effectively in the same band unless the separation distance is guranteed and/or some form of interference mitigation technique is employed such as dynamic channel allocation.

PBB-TE 기반의 패킷전송시스템에서 멀티캐스트 서비스와 계층적 QoS 구현

이원경(Wonkyoung Lee),최창호(Chang-Ho Choi),김선미(Sun-Me Kim) 한국통신학회 2012 韓國通信學會論文誌 Vol.37 No.6

복수 무인기 운용을 위한 시스템의 구성과 이를 적용한 목표물 추적 임무 비행실험

이성헌,김영주,정우영,김찬호,탁기현,방효충 한국항공우주학회 2014 한국항공우주학회 학술발표회 논문집 Vol.2014 No.11

본 논문은 복수 무인기 운용을 위해 사용한 네트워크 시스템과 지상 통제 및 모니터링(이하 지상국) 시스템에 대해 설명하고, 이를 본 연구실에서 보유하고 있는 무인기들에 적용하여 목표물 추적 임무를 수행한 비행실험 결과를 간략하게 소개한다. 복수 무인기들이 효율적으로 운용되기 위해서는 무인기와 지상국 사이의 네트워크 구성뿐만 아니라 무인기 상호간의 자율적인 정보공유를 요하며, 사용자 친화적인 지상국 인터페이스를 구성하여 단일 사용자도 손쉽게 다수의 무인기들을 통제할 수 있는 시스템의 설계가 필요하다. 이러한 시스템을 구축하기 위하여 하드웨어를 어떠한 방식으로 구성하였는지, 네트워크 시스템 측면에서 늘어난 데이터의 처리와 식별문제는 어떻게 해소하였는지, 지상국의 구현은 어떻게 이루어져 있는지를 각각의 하위체제로 나누어 설명한다. This paper gives an explanation for network system and GCS(Ground Control System) can be used to operate multiple UAVs at the same time. Moreover, by applying these systems into three different UAVs, we have conducted several flight tests regarding target tracking mission, and the result will be introduced at the end of this paper. In order to multiple UAVs are being operated efficiently even by single user, inter-vehicle communications and user friendly GCS interfaces should be implemented. System details such as how to construct hardware system, how to cope with increased amount of data, and realize GCS to be more readable will be presented.