• Journal of Korea Multimedia Society
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• v.9 no.7
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• pp.844-853
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• 2006

The IEEE 802.17 Resilient Packet Ring (RPR) for future Local, Metropolitan, and Wide Area Networks was recently standardized, but it still suffer from delay jitter deterioration and even some bandwidth loss under unbalanced overload. In order to overcome these drawbacks, this paper proposes a bandwidth redistribution based fairness control method, compatible with the legacy one, in which each congested node measures the amount of available bandwidth of its bottleneck link resulted from regulating upstream nodes' shares of the link bandwidth, calculates optimal fair rate with the number of uptream nodes requiring more bandwidth, and then redistributes the available bandwidth to the upstream nodes by advertising the rate. The performance evaluation results show that the proposed method fairly redistributes 95% of the bottleneck link bandwidth with even only two redistributions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.14 no.5
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• pp.453-461
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• 1989

Mean waiting time for each priority packet of each node in packet based priority token ring local area networks(LAN) was approximately analyzed using Bux's token ring LAN results which have not considered priority and Cohbam's head of line(HOL) priority results. In this paper, priority reservation method suggested in the IEEE 802.5 standard was not used. Relative error between numerical results which was presented in this paper and simulation results was identified by +-5%. For traffic intenity, number of node, packet length, transmission speed, line length, token latency, number of priority class and traffic percentage to some heavy trafficd node, mean waiting time of each priority was analyzed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.1
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• pp.157-176
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• 2011

An interest-based P2P constructs the peer connections based on similarities for efficient search of resources. A clustering technique using peer similarities as data is an effective approach to group the most relevant peers. However, the separation of groups produced from clustering lowers the scalability of a P2P network. Moreover, the interest-based approach is only concerned with user-level grouping where topology-awareness on the physical network is not considered. This paper proposes an efficient scalable search for the interest-based P2P system. A scalable multi-ring (SMR) based on fuzzy clustering handles the grouping of relevant peers and the proposed scalable search utilizes the SMR for scalability of peer queries. In forming the multi-ring, a minimized route function is used to determine the shortest route to connect peers on the physical network. Performance evaluation showed that the SMR acquired an accurate peer grouping and improved the connectivity rate of the P2P network. Also, the proposed scalable search was efficient in finding more replicated files throughout the peer network compared to other traditional P2P approaches.

• Convergence Security Journal
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• v.23 no.1
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• pp.3-8
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• 2023

Multi-domain optical transport networks are not fundamentally interoperable and require an integrated orchestration mechanism and path provision mechanism at the entire network level. In addition, ensuring network survivability is one of the important issues. MPLS-TP (Multi-Protocol Label Switching-Transport Profile) defines various protection/recovery methods as standards, but does not mention how to calculate and select protection/recovery paths. Therefore, an algorithm that minimizes protection/recovery collisions at the optical circuit packet integrated network level and calculates and sets a path that can be rapidly protected/recovered over the entire integrated network area is required. In this paper, we proposed an algorithm that calculates and sets up a path that can be rapidly protected and restored in a T-SDN network composed of multiple ring-mesh topology.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.10
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• pp.79-88
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• 2003

We demonstrate a novel all-optical packet switching system that is suitable for optical ring networks. For the demonstration, video signals are encoded into optical packets which are composed of header and payload. The optical packets are all-optically processed at a switching node based on all-optical header processor, packet-level clock extraction, bit-level clock extraction, all-optical data format converter and so on.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.178-180
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• 1996

An Inductive high-Tc superconducting fault current limiter using YBCO superconducting ring in the secondary part has many advantages in power networks. It is based on the appearance of resistivity in the superconductors and this paper is studied on the relation between the resistivity and the temperature of superconductors. In many other devices using superconductors, it is important to prohibit the superconductors from quenching for the protection of the whole system, or at least the superconductors.ᢁ

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.172-175
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• 1999

In this paper, we propose new algorithm to minimize the total cost of overall system in WDM ring networks. The cost of system includes the number of SONET ADMs as well as the number of wavelength. As optical technologies and WDM components are developed, the dominant cost of system is the number of SONET ADMs which is electronic equipment. To reduce the number of SONET ADMs in nonuniform traffic, we propose two algorithms one is the algorithm to construct full circles as many as possible to minimize gaps by cutting and combining the connections. The other is the algorithm to groom circles Into a wavelength to share the maximum number of nodes. The simulation results show that the proposed algorithm is superior to conventional algorithm in nonuniform traffic

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.9
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• pp.2017-2036
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• 2012

Based on the current solutions to the problem of energy hole, this paper proposed a nonuniform node distribution clustering algorithm, NNDC. Firstly, we divide the network into rings, and then have an analysis and calculation on nodes' energy consumption in each ring of the network when clustering algorithm is applied to collect data. We also put forward a scheme of nonuniform node distribution on the basis of the proportion of nodes' energy consumption in each ring, and change nodes' active/hibernating states under density control mechanism when network coverage is guaranteed. Simulation shows NNDC algorithm can satisfyingly balance nodes' energy consumption and effectively avoid the problem of energy hole.

• Proceedings of the Korean Information Science Society Conference
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• 2000.04a
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• pp.609-611
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• 2000

WWW의 대중화를 통한 인터넷 사용자의 증가로 발생되는 통신지연의 해결책으로 웹 캐싱 방법이 고려되어 왔다. 웹 서버의 용량초과로 서비스시스템을 확장하고자 할 때 서버 운영자의 측면에서는 사용자의 서비스 응답시간을 줄이는 것 못지 않게 서버를 확장하고 유지하는데 드는 비용을 최소화하는 것도 중요한 사항이다. 그러므로 본 논문에서는 인터넷상에서 프락시가 될 수 있는 잠재노드들이 양방향 통신을 지원하는 링크들로 선형(linear)과 고리(ring) 구조를 이룰 때 서비스 노드들 각각이 정해진 임계 응답시간을 보장하기에 필요한 최소한의 프락시의 개수와 그의 위치를 동시에 찾아내는 알고리즘을 제안한다. 여기서 프락시의 위치는 위상의 어느 족에 위치해도 무방하다고 본다.

• Proceedings of the KIEE Conference
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• 1995.07a
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• pp.131-133
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• 1995

Inductive high-Tc superconducting fault current limiter using YBCO superconducting ring in the secondary part has many advantages in power networks. It is based on the superconducting to normal transition and this paper describes its operational characteristics and experimental results, especially focused on the harmonic component analysis and recovery time. We fabricated and tested it under various conditions for the analysis of transient fault characteristics. And for the analysis of harmonics we used FFT methods. The superconducting ring was quenched in 240Arms and fault current was effectively limited to the lower current level. In addition, it was fast recovered when the fault condition was removed and after fault the system had odd harmonics.