close
1.
Article
Kyushu Univ. Production Kyushu Univ. Production
Cover image of スケーラビリティを考慮したIPマルチキャストアーキテクチャの設計 — Design of Scalable Inter-Domain IP Multicast Architecture
大森, 幹之; Ohmori, Motoyuki; 岡村, 耕二 ... [et al.]
Publication info: 2000-11-01.
View fulltext:
Abstract: In this paper, we design the scalable inter-domain IP multicast architecture and achieve IP multicast routing over the whole Internet. In our architecture, we propose the dynamical address allocation in order to aggregate addresses efficiently. And for the sake of more flexible address allocation, we define two kind of multicast addresses, which are called VMA(Virtual Multicast Address) and MAR(Multicast Address for Routing). We present amount of routing information with our architecture, and consider inter-operability with other routing protocols. Read more
2.
Article
Kyushu Univ. Production Kyushu Univ. Production
Cover image of 研究開発用ギガビットネットワーク(JGN)について
岡村, 耕二
Publication info: 九州大学情報基盤センター広報 : 学内共同利用版. 2, (1), pp. 1-6, 2002-03. Research Institute for Information Technology
View fulltext:
Table of Contents:
1.研究開発用ギガビットネットワーク(JGN) 2.九州大学における研究開発事例 3.JGN IPv6 4.おわりに
1.研究開発用ギガビットネットワーク(JGN) 2.九州大学における研究開発事例 3.JGN IPv6 4.おわりに
3.
Article
Kyushu Univ. Production Kyushu Univ. Production
Cover image of キャンパス間接続のギガビット化および対外接続の高速化について
岡村, 耕二
Publication info: 九州大学情報基盤センター広報 : 学内共同利用版. 3, (1), pp. 24-26, 2003-03. Research Institute for Information Technology
View fulltext:
Table of Contents:
1.はじめに 2.キャンパス間のギガビット化について 3.対外接続の高速化 4.おわりに
1.はじめに 2.キャンパス間のギガビット化について 3.対外接続の高速化 4.おわりに
4.
Article
Kyushu Univ. Production Kyushu Univ. Production
Cover image of 元岡キャンパスのネットワーク計画について
岡村, 耕二
Publication info: 九州大学情報基盤センター広報 : 学内共同利用版. 5, (1), pp. 1-6, 2005-04. Research Institute for Information Technology
View fulltext:
Table of Contents:
1.はじめに 2.平成17年度設備計画 3.基本構成 4.ネットワークの導入スケジュール 5.元岡への引越し 6.おわりに
1.はじめに 2.平成17年度設備計画 3.基本構成 4.ネットワークの導入スケジュール 5.元岡への引越し 6.おわりに
5.
Article
Kyushu Univ. Production Kyushu Univ. Production
Cover image of ICOIN-15国際会議に出席して
岡村, 耕二
Publication info: 九州大学情報基盤センター広報 : 全国共同利用版. 1, (2), pp. 117-118, 2001-07. Computing and Communications Center Kyushu University
View fulltext:
6.
Article
Kyushu Univ. Production Kyushu Univ. Production
Cover image of ECN Based Multi-path Mechanism for VoIP Transmission
Kang, Joonsuk; Okamura, Koji; 姜, 俊錫 ... [et al.]
Publication info: Research reports on information science and electrical engineering of Kyushu University. 17, (2), pp. 41-48, 2012-09-26. Faculty of Information Science and Electrical Engineering, Kyushu University
View fulltext:
Abstract: By the remarkable improvement of physical performance of networks (such as speed, capacity, etc) which consist of Internet and the diffusion of high-end terminals such as smart-phones, voice over IP (VoIP) is becoming one of the major communication technologies. However current packet networks still can not provide a stable transmission quality and it can cause VoIP call quality degradation. Especially, the main factor affecting VoIP quality is congestion across a network. Multi-homing can be a good solution to avoid points of congestion in the network. We therefore propose Real Time & Multi-path Transmission Protocol (RTMTP), a transport layer protocol in which multiple path real-time transport and effective congestion control are available. Our protocol uses the explicit congestion notification (ECN) mechanism to detect network congestion level and to control transmission rate of VoIP traffic at the sender side. To maximize network bandwidth efficiency of multiple paths, the RTMTP shifts traffic among those paths. Our simulation results show that RTMTP improves VoIP data transmission throughput by effectively utilizing multi-path without voice call quality degradation, and helps users to use more inexpensive access network as much as possible while maintaining an acceptable voice quality. Read more
7.
Article
Kyushu Univ. Production Kyushu Univ. Production
Cover image of A remote surgery experiment between Japan and Thailand over Internet using a low latency CODEC system
Arata, Jumpei; 荒田, 純平; Takahashi, Hiroki ... [et al.]
Publication info: Proceedings of the IEEE International Conference on Robotics and Automation. 2007, pp. 953-959, 2007-04. IEEE
View fulltext:
Abstract: Remote surgery is one of the most desired applications in the context of recent advanced medical technologies. For a future expansion of remote surgery, it is important to use conventional network infrastructures such as Internet. However, using such conventional network infrastructures, we are confronting time-delay problems of data transmission. In this paper, a remote surgery experiment between Japan and Thailand using a Research and Development Internet is presented. In the experiment, the image and audio information was transmitted by a newly developed low latency CODEC system to shorten the time-delay. By introducing the low latency CODEC system, the time-delay was shortened compared with the past remote surgery experiments despite the longer distance. We also conducted several network measurements such as a comparison between TCP/IP and UDP/IP about the control signal transmission. Read more
8.
Article
Kyushu Univ. Production Kyushu Univ. Production
Cover image of 日本-タイ遠隔手術実験 — Remote Surgery Experiment between Japan-Thailand
荒田, 純平; Arata, Jumpei; 高橋, 弘樹 ... [et al.]
Publication info: 日本ロボット学会学術講演会予稿集. 24, 2006-09. The Robotics Society of Japan
View fulltext:
Abstract: In this paper, a remote surgery experiment, which was conducted between Japan and Thailand by using the developed minimally surgical system is described. In the experiment, a laparoscopic cholecystectomy was successfully performed on a pig. Various network measurements were conducted for the evaluation of the remote surgery. Read more
9.
Article
Kyushu Univ. Production Kyushu Univ. Production
Cover image of 日韓遠隔医療システムの構築 : 超高速遠隔医療システムの意義
清水, 周次; Shimizu, Shuji; 中島, 直樹 ... [et al.]
Publication info: 月刊新医療. 32, (2), pp. 125-127, 2005-02-01. エムイー振興協会
View fulltext:
Abstract: We have established a high-quality teleconference system between Korea and Japan through submarine optic cable on big broadband Internet. Broadcasting real-time surgery and teleconference with medical-quality videos was so useful to learn surgical techniques and other medical procedures. With these experiences and current achievements, we hope to extend this advanced network system to whole Asian countries to share our medical skills and international friendship. Read more
10.
Article
Kyushu Univ. Production Kyushu Univ. Production
Cover image of 日韓遠隔医療システムの構築 : 非圧縮デジタル動画像のインターネット配信 — High-Quaity Telemedicine via Korea-Japan Cable Network : Digital Video Transport System over Internet Protocol
清水, 周次; Shimizu, Shuji; 中島, 直樹 ... [et al.]
Publication info: 遠隔医療研究会論文集. 8, pp. 54-55, 2004-08-21. 遠隔医療システム研究会
View fulltext:
Abstract: A broad-banded medical network was established between Korea and Japan using Digital Video Transport System (DVTS) over Internet protocol. We used Kyushu GigaPOP (QGPOP) (Japanese side), the Korea Advanced Research Network (Korean side), and the Korea-Japan Cable Network (international line). The teleconferences with real-time transmission of laparoscopic surgery, neurosurgery, and endoscopic examination were successfully performed. The bandwidth was 30 Mbps for a line of transmission and two lines of DVTS were utilized. The uncompressed moving image had the rate of 30 per second. The security software was also used to protect patient privacy. This international telecommunication using high-quality moving image is very helpful for the exchange of new medical techniques among different countries. Read more