• Title/Summary/Keyword: K-Shortest Paths

Search Result 111, Processing Time 0.025 seconds

A Nearly Optimal One-to-Many Routing Algorithm on k-ary n-cube Networks

  • Choi, Dongmin;Chung, Ilyong
    • Smart Media Journal
    • /
    • v.7 no.2
    • /
    • pp.9-14
    • /
    • 2018
  • The k-ary n-cube $Q^k_n$ is widely used in the design and implementation of parallel and distributed processing architectures. It consists of $k^n$ identical nodes, each node having degree 2n is connected through bidirectional, point-to-point communication channels to different neighbors. On $Q^k_n$ we would like to transmit packets from a source node to 2n destination nodes simultaneously along paths on this network, the $i^{th}$ packet will be transmitted along the $i^{th}$ path, where $0{\leq}i{\leq}2n-1$. In order for all packets to arrive at a destination node quickly and securely, we present an $O(n^3)$ routing algorithm on $Q^k_n$ for generating a set of one-to-many node-disjoint and nearly shortest paths, where each path is either shortest or nearly shortest and the total length of these paths is nearly minimum since the path is mainly determined by employing the Hungarian method.

Performance Evaluation of a Survivable Ship Backbone Network Exploiting k-Shortest Disjoint Paths (k-최단 분리 경로 배정을 적용한 장애 복구형 선박 백본 네트워크의 성능 평가)

  • Tak, Sung-Woo
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.16 no.4
    • /
    • pp.701-712
    • /
    • 2012
  • The concept of $k$-shortest disjoint paths is considered important because the establishment of primary and backup forwarding paths exploiting shorter distance and faster propagation time is a dominant consideration for the design of a survivable backbone network. Therefore, we need to evaluate how well the concept of $k$-shortest disjoint paths is exploited for the design of a survivable ship backbone network considering the international standard related to ship backbone networks, the IEC61162-410 standard specifying how to manage redundant message transmissions among ship devices. Performance evaluations are conducted in terms of following objective goals: link capacity, hop and distance of primary and backup paths, even distribution of traffic flows, restoration time of backup forwarding paths, and physical network topology connectivity.

Design of a set of One-to-Many Node-Disjoint and Nearly Shortest Paths on Recursive Circulant Networks

  • Chung, Ilyong
    • Journal of Korea Multimedia Society
    • /
    • v.16 no.7
    • /
    • pp.897-904
    • /
    • 2013
  • The recursive circulant network G(N,d) can be widely used in the design and implementation of parallel processing architectures. It consists of N identical nodes, each node is connected through bidirectional, point-to-point communication channels to different neighbors by jumping $d^i$, where $0{\leq}i{\leq}{\lceil}{\log}_dN{\rceil}$ - 1. In this paper, we investigate the routing of a message on $G(2^m,4)$, a special kind of RCN, that is key to the performance of this network. On $G(2^m,4)$ we would like to transmit k packets from a source node to k destination nodes simultaneously along paths on this network, the $i^{th}$ packet will be transmitted along the $i^{th}$ path, where $1{\leq}k{\leq}m-1$, $0{{\leq}}i{{\leq}}m-1$. In order for all packets to arrive at a destination node quickly and securely, we present an $O(m^4)$ routing algorithm on $G(2^m,4)$ for generating a set of one-to-many node-disjoint and nearly shortest paths, where each path is either shortest or nearly shortest and the total length of these paths is nearly minimum since the path is mainly determined by employing the Hungarian method.

Shortest Path Analyses in the Protein-Protein Interaction Network of NGAL (Neutrophil Gelatinase-associated Lipocalin) Overexpression in Esophageal Squamous Cell Carcinoma

  • Du, Ze-Peng;Wu, Bing-Li;Wang, Shao-Hong;Shen, Jin-Hui;Lin, Xuan-Hao;Zheng, Chun-Peng;Wu, Zhi-Yong;Qiu, Xiao-Yang;Zhan, Xiao-Fen;Xu, Li-Yan;Li, En-Min
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.16
    • /
    • pp.6899-6904
    • /
    • 2014
  • NGAL (neutrophil gelatinase-associated lipocalin) is a novel cancer-related protein involves multiple functions in many cancers and other diseases. We previously overexpressed NGAL to analyze its role in esophageal squamous cell carcinoma (ESCC). In this study, a protein-protein interaction (PPI) was constructed and the shortest paths from NGAL to transcription factors in the network were analyzed. We found 28 shortest paths from NGAL to RELA, most of them obeying the principle of extracellular to cytoplasm, then nucleus. These shortest paths were also prioritized according to their normalized intensity from the microarray by the order of interaction cascades. A systems approach was developed in this study by linking differentially expressed genes with publicly available PPI data, Gene Ontology and subcellular localizaton for the integrated analyses. These shortest paths from NGAL to DEG transcription factors or other transcription factors in the PPI network provide important clues for future experimental identification of new pathways.

Generating Multiple Paths by Using Multi-label Vine-building Shortest Path Algorithm (수정형 덩굴망 최단경로 탐색 알고리즘을 이용한 다경로 생성 알고리즘의 개발)

  • Kim, Ik-Ki
    • Journal of Korean Society of Transportation
    • /
    • v.22 no.2 s.73
    • /
    • pp.121-130
    • /
    • 2004
  • In these days, multiple-path generation method is highly demanded in practice and research areas, which can represents realistically travelers behavior in choosing possible alternative paths. The multiple-path generation algorithm is one of the key components for policy analysis related to ATIS, DRGS and ATMS in ITS. This study suggested a method to generate multiple Possible paths from an origin to a destination. The approach of the suggested method is different from an other existing methods(K-shortest path algorithm) such as link elimination approach, link penalty approach and simulation approach. The result of the multi-label vine-building shortest path algorithm(MVA) by Kim (1998) and Kim(2001) was used to generate multiple reasonable possible paths with the concept of the rational upper boundary. Because the MVA algorithm records the cost, back-node and back-back node of the minimum path from the origin to the concerned node(intersection) for each direction to the node, many potential possible paths can be generated by tracing back. Among such large number of the potential possible paths, the algorithm distinguishes reasonable alternative paths from the unrealistic potential possible paths by using the concept of the rational upper boundary. The study also shows the very simple network examples to help the concept of the suggested path generation algorithm.

A Study on Algorithms for Calculating the k-Maximum Capacity Paths in a Network (K-최대용량경로(最大容量經路) 계산법(計算法)에 관한 연구(硏究))

  • Kim, Byung-Su;Kim, Chung-Young
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.19 no.2
    • /
    • pp.105-117
    • /
    • 1993
  • Methods for calculating k shortest paths in a network system, are based on a analogy which exists between the solution of a network problem and traditional techniques for solving linear equations. This paper modifies an algebraic structure of the K shortest path method and develops k maximum flow methods. On the basis of both theoretical and algebraic structure, three iteration methods are developed and the effective procedure of each method are provided. Finally, computational complexity is discussed for those methods.

  • PDF

An Efficient Distributed Algoritm for the Weighted Shortest-path Updating Problem (최단 경로 갱신문제를 해결하는 분산알고리듬)

  • Park, Jeong-Ho;Lee, Gyeong-O;Gang, Gyu-Cheol
    • The Transactions of the Korea Information Processing Society
    • /
    • v.7 no.6
    • /
    • pp.1778-1784
    • /
    • 2000
  • We consider the weighted shortest path updating problem, that is, the problem to reconstruct the weighted shortest paths in response to topology change of the network. This appear proposes a distributed algorithms that reconstructs the weighted shortest paths after several processors and links are added and deleted. its message complexity and ideal-time complexity are O(p$^2$+q+n') and O(p$^2$+q+n') respectively, where n' is the number of processors in the network after the topology change, q is the number of added links, and p is the total number of processors in he biconnected components (of the network before the topology change) including the deleted links or added links.

  • PDF

The Top-K QoS-aware Paths Discovery for Source Routing in SDN

  • Chen, Xi;Wu, Junlei;Wu, Tao
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.12 no.6
    • /
    • pp.2534-2553
    • /
    • 2018
  • Source routing is the routing scheme that arranges the whole path from source to target at the origin node that may suit the requirements from the upper layer applications' perspective. The centralized control in SDN (Software-Defined Networking) networks enables the awareness of the global topology at the controller. Therefore, augmented source routing schemes can be designed to achieve various purposes. This paper proposes a source routing scheme that conducts the top-K QoS-aware paths discovery in SDN. First, the novel non-invasive QoS over LLDP scheme is designed to collect QoS information based on LLDP in a piggyback fashion. Then, variations of the KSP (K Shortest Paths) algorithm are derived to find the unconstrained/constrained top-K ranked paths with regard to individual/overall path costs, reflecting the Quality of Service. The experiment results show that the proposed scheme can efficiently collect the QoS information and find the top-K paths. Also, the performance of our scheme is applicable in QoS-sensitive application scenarios compared with previous works.

Multi-constrained Shortest Disjoint Paths for Reliable QoS Routing

  • Xiong, Ke;Qiu, Zheng-Ding;Guo, Yuchun;Zhang, Hongke
    • ETRI Journal
    • /
    • v.31 no.5
    • /
    • pp.534-544
    • /
    • 2009
  • Finding link-disjoint or node-disjoint paths under multiple constraints is an effective way to improve network QoS ability, reliability, and so on. However, existing algorithms for such scheme cannot ensure a feasible solution for arbitrary networks. We propose design principles of an algorithm to fill this gap, which we arrive at by analyzing the properties of optimal solutions for the multi-constrained link-disjoint path pair problem. Based on this, we propose the link-disjoint optimal multi-constrained paths algorithm (LIDOMPA), to find the shortest link-disjoint path pair for any network. Three concepts, namely, the candidate optimal solution, the contractive constraint vector, and structure-aware non-dominance, are introduced to reduce its search space without loss of exactness. Extensive simulations show that LIDOMPA outperforms existing schemes and achieves acceptable complexity. Moreover, LIDOMPA is extended to the node-disjoint optimal multi-constrained paths algorithm (NODOMPA) for the multi-constrained node-disjoint path pair problem.

A Study on Optimal Planning of Sustainable Rural Road Path based on Infrastructure for Green-Tourism and Public Service (그린투어리즘 및 공공서비스 기반의 지속가능한 농촌도로노선의 최적계획에 관한 연구)

  • Kim, Dae-Sik;Chung, Ha-Woo
    • Journal of Korean Society of Rural Planning
    • /
    • v.11 no.1 s.26
    • /
    • pp.1-8
    • /
    • 2005
  • The purpose of this study is to develop a simulation model of rural road path for infrastructure of green-tourism and public service in rural areas. This study makes an objective function for moving cost minimization considering car travel time according to road characteristics, which can route the optimal shortest road paths between the center places and all rear villages, based on GIS coverages of road-village network for connecting between center places and rural villages as input data of the model. In order to verify the model algorithm, a homogeneous hexagonal network, assuming distribution of villages with same population density and equal distance between neighborhood villages on a level plane area, was tested to simulate the optimal paths between the selected center nodes and the other rear nodes, so that the test showed reasonable shortest paths and road intensity defined in this study. The model was also applied to the actual rural area, Ucheon-myun, which is located on Hoengsung-gun, Kangwon-do, with 72 rural villages, a center village (Uhang, 1st center place) in the area, a county conte. (Hoengsung-eup, 2nd center place), and a city (Wonju, 3rd center place), as upper settlement system. The three kinds of conte. place, Uhang, Hoengsung-eup, and Wonju, were considered as center places of three scenarios to simulate the optimal shortest paths between the centers and rural villages, respectively. The simulation results on the road-village network with road information about pavement and width of road show that several spans having high intensity of road are more important that the others, while some road spans have low intensity of road.