• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.109-112
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• 2005

In this paper, we propose an improved delay-constrained unicast routing (I-DCUR) algorithm for real-time networks which is based on the delay-constrained unicast routing (DCUR) algorithm. Our I-DCUR algorithm is quite different from DCUR algorithm, because the node will choose the link between the active node and the previous node, and it will replace the original loop path when it detects a loop. Thus, firstly consider to choose the link between the active node and the previous node to replace the original loop path when a node detects a loop. So our algorithm can make the construction of path more efficiently, as compared to DCUR algorithm. We could see that the performance of I-DCUR algorithm is much better than DCUR algorithm in the experimental results. There were over 40% improvement in 100 nodes, 60% in 200 nodes, and 9% reduction of costs.

• Journal of Korea Multimedia Society
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• v.18 no.10
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• pp.1225-1230
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• 2015

Mobile Sensor Networks (MSN) is composed of a distributed collection of mobile sensor nodes, each of which has sensing, computation, communication and locomotion capabilities. Since the routing path can be broken when some nodes on the path move to other position, MSN may have a high rate of communication failure. So, MSN has to provide a means for low-cost and low-power routing to support mobility of sensor nodes. In this paper, a limited flooding scheme for routing in MSN is proposed to allow efficient energy utilization without requiring any complicated tasks for path maintenance.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.5B
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• pp.304-309
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• 2005

In this paper, we propose a localized Adaptive QoS Routing using TD method and evaluate performance of various exploration methods when path is selected. Expecially, through extensive simulation, the proposed routing algorithm and exploration method using Exploration Bonus are shown to be effective in significantly reducing the overall blocking probability, when compared to the other path selection method(exploration method), because the proposed exploration method is more adaptive to network environments than others when path is selected.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.705-706
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• 2008

The feature of 6LoWPAN is the capability of the dynamic assignment of 16bit short addresses. By using this dynamically assigned short address, a hierarchical routing is employed. In case of node failure, this hierarchical routing don't support a technique for path recovery. So, this paper proposes the path recovery technique for hierarchical routing over 6LoWPAN.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.1
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• pp.222-233
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• 1995

For effective module generation, a detailed router which can handle complicated routing regions on multimple layers of interconnection under various constraints is necessary. In this paper, a new improved maze routing technique is described, which can find the shortest path for each net without allowing stacked vias. In this method, two cost values are stored at each grid point. The cost values represent the routing costs from the terminal of the net being routed to the grid point. One cost value shows the cost of the shortest path without making a via at the grid point and the other cost value shows that with making a via at the grid point. This is the first systematic maze routing technique which can find the shortest path without via-stacking.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04a
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• pp.367-369
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• 2001

GSPA(Generic Shortest Path Algorithm)은 각종 정보통신 네트워크 상에서 멀티미디어 정보전송시 요구되는 QoS 기반의 라우팅을 위한 새로운 라우팅 알고리즘이다. 전체적인 동작은 원시노드(Source Node)에서 목적노드(Destination Node) 사이에서 이전 단계의 재귀호출에서 찾은 최단 경로를 기준으로 해서 이웃 노드들을 대상으로 재귀호출을 통해서 QoS 요구조건을 만족하는 경로정보를 기록하면서 최단 경로를 찾는 알고리즘이다. GSPA는 기존 Distance Vector 알고리즘이 경로를 설정하기 위해 많은 시간과 대역폭을 낭비하며 네트워크 형상이 수시로 변경될 때 “Counting to Infinity”현상을 발생시키는 단점을 보완하고, Link-State 데이터 베이스를 이용해서 함수 재귀호츨을 통해서 최단 경로를 찾아냄으로써 구현하기가 쉬운 알고리즘이다. 또, Distance-Vector와 Link-State 알고리즘의 장점을 수용하였으며, 이 알고리즘을 분산 네트워크 환경에서 동작하도록 수정하면 분산 네트워크 환경에서의 Hierarchical Routing, Multi-Path Routing, QoS Routing을 위한 기본 알고리즘으로 매우 좋은 특성들을 가지고 있다. 본 논문에서는 이 알고리즘을 소개하고 간단한 예를 통해 기본 동작에 대해 살펴본다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.6
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• pp.2534-2553
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• 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.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.3
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• pp.287-299
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• 2000

In this paper, we classify multicast methods into three categories, i.e., tree-based, path-based, and hybrid-based multicasts, for a multicomputer employing the bidirectional torus network and wormhole routing. We propose the dynamic partition multicast routing (DPMR) as a path-based algorithm. As a hybrid-based algorithm, we suggest the hybrid multicast routing (HMR), which employs the tree-based approach in the first phase of routing and the path-based approach in the second phase. Performance is measured in terms of the average latency for various message length to compare three multicast routing algorithms. We also compare the performance of wormhole routing having variable buffer size with virtual cut-through switching. The message latency for each switching method is compared using the DPMR algorithm to evaluate the buffer size trade-off on the performance.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.6
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• pp.736-741
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• 2005

The highly popular algorithm to determine routing path for the multi-hopping wireless sensor network is DSR(Dynamic Source Routing), which is one of the Demand-Driven way to makes the route only when there is a request for sending data. However, because DSR attaches the route's record on the sending packet, the bigger number of sensor node is, the heavier packet in DSR becomes. In this paper, we try to propose the new optimal routing path selecting algorithm which does not make the size of packet bigger by using proper routing table even though the number of sensor node increases, and we try to show our algorithm is more stable and reliable because it is based on the cost function considering some network resources of each sensor node such as power consumption, mobility, traffic in network, distance(hop) between source and destination.

• ETRI Journal
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• v.43 no.4
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• pp.674-683
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• 2021

A trust-aware secure routing protocol (TSRP) for wireless sensor networks is proposed in this paper to defend against varieties of attacks. First, each node calculates the comprehensive trust values of its neighbors based on direct trust value, indirect trust value, volatilization factor, and residual energy to defend against black hole, selective forwarding, wormhole, hello flood, and sinkhole attacks. Second, any source node that needs to send data forwards a routing request packet to its neighbors in multi-path mode, and this continues until the sink at the end is reached. Finally, the sink finds the optimal path based on the path's comprehensive trust values, transmission distance, and hop count by analyzing the received packets. Simulation results show that TSRP has lower network latency, smaller packet loss rate, and lower average network energy consumption than ad hoc on-demand distance vector routing and trust based secure routing protocol.