研究者詳細 - 西　宏章

論文 - 西　宏章

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A router-based management system for prediction of network congestion

Erwin Harahap, Janaka Wijekoon, Rajitha Tennekoon, Fumito Yamaguchi, Shinichi Ishida, Hiroaki Nishi

International Workshop on Advanced Motion Control, AMC （IEEE） 398 - 403 2014年

査読有り, ISSN 1943-6572

Network Management System (NMS) plays an important role in networks to maintain the best performance of a network. It employs variety of tools, applications, and devices in order to support network administrators to monitor and maintain the stability of a network. Fault management is part where the NMS dealing with problems and failures, such as congestion, in the network. Generally, most NMSs use Simple Network Management Protocol (SNMP) to monitor and map network availability, performance, and error rates. In the existing NMS process, an SNMP agent is deployed to get information about the network condition and then send them to the administrator for taking further action on solving the problems. However, deploying such agent to the network may increase the traffic density. On the other hand, packet latency and RTT will increase as well. In this paper, we implemented a prototype of the proposing novel system that no need to deploy such agent to obtain network information. Our system analyze the streaming traffic by implementing a Service-oriented Router (SoR). Our objective is to predict a congestion in the specific link in the network through a router-based data traffic analysis using a Bayesian network model. The purpose of the prediction is to support the network administrator to notify the early warning regarding to the fault in the network as long as possible before it actually happening. By this prediction, the network administrator can immediately taking action to avoid the problems.We provided simulation experiment to demonstrate the performance of the proposed system. Our simulation results show that the proposed system can predict a congestion link caused by a particular problem, before hand it is getting congested. © 2014 IEEE.

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Per hop data encryption protocol for transmission of motion control data over public networks

Rajitha Tennekoon, Janaka Wijekoon, Erwin Harahap, Hiroaki Nishi, Eiichi Saito, Seiichiro Katsura

International Workshop on Advanced Motion Control, AMC （IEEE） 128 - 133 2014年

査読有り, ISSN 1943-6572

Bilateral controllers are widely used vital technology to perform remote operations and telesurgeries. The nature of the bilateral controller enables control objects, which are geographically far from the operation location. Therefore, the control data has to travel through public networks. As a result, to maintain the effectiveness and the consistency of applications such as teleoperations and telesurgeries, faster data delivery and data integrity are essential. The Service-oriented Router (SoR) was introduced to maintain the rich information on the Internet and to achieve maximum benefit from networks. In particular, the security, privacy and integrity of bilateral communication are not discoursed in spite of its significance brought by its underlying skill information or personal vital information. An SoR can analyze all packet or network stream transactions on its interfaces and store them in high throughput databases. In this paper, we introduce a hop-by-hop routing protocol which provides hop-by-hop data encryption using functions of the SoR. This infrastructure can provide security, privacy and integrity by using these functions. Furthermore, we present the implementations of proposed system in the ns-3 simulator and the test result shows that in a given scenario, the protocol only takes a processing delay of 46. 32 μs for the encryption and decryption processes per a packet. © 2014 IEEE.

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Per-hop data encryption protocol for transmitting data securely over public networks

Rajitha Tennekoon, Janaka Wijekoon, Erwin Harahap, Hiroaki Nishi

Procedia Computer Science （ELSEVIER SCIENCE BV） 32 965 - 972 2014年

査読有り, ISSN 1877-0509

It is a well-known fact that the Internet traffic travels through public networks. These networks lack security and are vulnerable. Encryption and public key cryptography are important technologies that are used to preserve data security and integrity, and to reduce information theft on the public networks. However, the existing routing protocols are incapable of providing secure data transmission on public networks. To this end, our laboratory introduced the Service-oriented Router (SoR) to maintain rich information for the next-generation networks by shifting the current Internet infrastructure to an information-based and an open-innovation platform. An SoR can analyze all packet stream transactions on its interfaces and store them in high throughput databases. Using the features of the SoR, in this paper, we propose a hop-by-hop routing protocol that provides per-hop data encryption. This infrastructure is proposing to preserve both the security and the privacy of data that traverses through public networks. We implemented a prototype of per-hop data encryption protocol on the ns-3 simulator and the results obtained are discussed in this paper. © 2014 Published by Elsevier B.V.

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DC-Balanced Perfect Classified Channel for Hiding Farming Signal

西宏章

IEEJ Transactions on Electronic Engineering （The Institute of Electrical Engineers of Japan） 8 （ 6 ） 610 - 615 2013年11月

研究論文（学術雑誌）, 共著, 査読有り, ISSN 1931-4973

Perfect classified channel (PCC) was proposed as a hardware-based Layer-1 encryption system that prevents of leakage of packet information and any indication of the existence of packets. PCC can provide high-throughput communication, which is encrypted using AES encryption hardware, while maintaining DC balancing, which is generally managed using the 8B/10B or 64B/66B coding algorithms. In this paper, we propose two methods to classify a framing signal that indicates a boundary between packets, for PCC. These methods facilitate an improved level of security compared with existing communication channels and make PCC more secure. This paper describes the details of the PCC architecture including the hardware costs while also verifying the DC-balance performance of PCC and the confidentiality of framing signals. © 2013 Institute of Electrical Engineers of Japan.

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HEMS環境におけるスマートフォンを用いた活動量の推定と空調制御への利用

伊東未奈子, 西宏章

組込みシステムシンポジウム2013論文集（IEEE） 2013 （ 2013 ） 140 - 146 2013年10月

ISSN 1553-572X

As a peak-cut or peak leveling control, heating, ventilation, and air conditioning (HVAC) are essential method for controlling the demand of electric power consumption. However, it is important to consider environmental amenity when designing control systems because the control may cause the deterioration of the amenity. In existing methods, metabolic equivalent (MET) values are not considered. Measurement and processing of MET values can be costly, requiring special infrastructure to both measure the values and communicate these values with a home energy management system (HEMS) or building energy management system (BEMS). This paper proposes a HVAC control method that considers the tradeoff between environmental amenity and energy conservation using the Keio University network oriented intelligent and versatile energy management system (KNIVES). The proposed method uses an iPod touch or iPhone application to obtain accurate measurements of both the MET value and the predicted mean vote (PMV). The accuracy of the PMV values after incorporation of MET estimates was confirmed experimentally. A HEMS experiment was conducted and a reduction in energy consumption was observed, demonstrating the usefulness of both the application and the proposed HVAC control method.

Modeling of Router-based Request Redirection for Content Distribution Network

Erwin Harahap, Janaka Wijekoon, Rajitha Tennekoon, Fumito Yamaguchi, Shinichi Ishida, an, Hiroaki Nishi

International Journal of Computer Applications 76 （ 13 ） 37 - 46 2013年08月

研究論文（学術雑誌）, 共著, 査読有り

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An Improved Cache Mechanism for Cache-based Network Processor

Hayato Yamaki a, Hiroaki Nishi

Journal of Communication and Computer 3 277 - 286 2013年03月

研究論文（学術雑誌）, 共著, 査読有り

A practical case study of HVAC control with MET measuring in HEMS environment

Minako Ito, Hiroaki Nishi

IECON Proceedings (Industrial Electronics Conference) （IEEE） 8136 - 8141 2013年

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Distributed algorithm for router-based management of replica server in next-CDN infrastructure

Erwin Harahap, Janaka Wijekoon, Rajitha Tennekoon, Fumito Yamaguchi, Shinichi Ishida, Hiroaki Nishi

Proceedings - 2013 International Conference on Cyber-Enabled Distributed Computing and Knowledge Discovery, CyberC 2013 （IEEE） 266 - 272 2013年

Extending Content Delivery Network (CDN) infrastructure that has features of router-based network management system (RNMS) is highly appealing and challenging. It allows developing a CDN architecture based upon standard design to ease interoperability, scalability, performance, and flexibility both on network monitoring and management controlled from a router. To better understand the system model, necessity, and the advantages of RNMS, this paper proposed an algorithm that distributed in to a special router called Service-oriented Router (SoR). The function of algorithm is to manage the effective and efficient number of replica server runs in the network. In CDN, minimizing the number of activated replica servers should be considered in order to reduce the operation cost of the system. We propose a semantic approached algorithm that has function to optimize the selection of active replica servers which managed from SoR. The algorithm has capability to find the best location of replica servers and performs load balancing among replica servers. Our simulation result indicates that the proposed algorithm can efficiently activate the replica servers according to user's request with 33.9% effective compared to other algorithm within about one millisecond RTT increase. © 2013 IEEE.

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Demand control of a pool by means of residual chlorine sensor

Tomoya Imanishi, Yasumasa Hayashi, Hiroaki Nishi

IECON Proceedings (Industrial Electronics Conference) （IEEE） 6344 - 6349 2013年

ISSN 1553-572X

Energy consumption is continuing to increase, especially the consumption of fossil fuels. It is important, therefore, to make use of our limited energy sources and reduce carbon dioxide emission. Some natural energy resources, such as solar power, have been well studied; however, they require complex systems and introduce energy fluctuations. On the other hand, demand side management (DSM) can also be studied from the consumer's point of view. One of the challenges associated with DSM is reducing the energy consumption of pumps in commercial buildings. Although water cycling systems have been well studied by large water departments, the knowledge is not generally used in most commercial facilities. Therefore, this study aims to control a water circulation pump to reduce energy consumption while maintaining water quality. This approach is applicable to buildings with pools or hot springs that are expensive to operate and maintain. Automation of water circulation systems has been well studied only by water departments. However, general water purification systems can be expensive and are highly complex. For these reasons, this paper constructs a low-cost automatic water management system to reduce management costs. An experiment was conducted to demonstrate an automatic water management system that will effectively cut water management costs using low-cost sensors. We also experimentally obtained some parameters to facilitate automatic water management. Finally, the experimental system was found to reduce electricity consumption by 8%/day and reduce the electric peak by 30%. © 2013 IEEE.

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Accurate indoor condition control based on PMV prediction in BEMS environments

Kenta Kuzuhara, Hiroaki Nishi

IECON Proceedings (Industrial Electronics Conference) （IEEE） 8142 - 8147 2013年

ISSN 1553-572X

Recently, there has been high demand for an efficient energy management system that decreases total energy consumption. The Great East Japan Earthquake of March 2011 resulted in the shutdown of nuclear power plants in Japan, thus limiting the supply of power. Since then, the need for an energy management system has become more pronounced in Japan. Such a situation warrants efficient energy consumption through the use of an energy management system. When heating, ventilation, and air conditioning are restricted, especially under peak-cut or peak-leveling control of electric power consumption, it should be ensured that the living environment is not uncomfortable for humans. However, in the existing methods, living environment comfort has not been considered practically in terms of the fundamental parameters, namely, volume, window size, and number of people in a given room, despite the considerable influence of these parameters on room amenity. In this study, we proposed a new control method that considers these parameters for maintaining the amenity index in indoor environments at a set value by predicting the predicted mean vote value. Furthermore, we set up a building energy management system in an office building in Kanagawa, Japan, to compare the proposed control method with an existing one. Two different cases were considered in this experiment: control using an existing method and control using the proposed method. The results show that the proposed method maintains the amenity index of the room at the desired level, while reducing peak and total power consumption levels. © 2013 IEEE.

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Feasibility study of service-oriented architecture for smart grid communications

Kenichi Takagiwa, Ryogo Kubo, Shinichi Ishida, Koichi Inoue, Hiroaki Nishi

IEEE International Symposium on Industrial Electronics （IEEE） 1 - 7 2013年

査読有り

This paper proposes a service-oriented network architecture for next-generation power grids, i.e., smart grids. The proposed architecture includes Ethernet passive optical network (EPON)-based optical access systems and service-oriented routers (SoRs). The SoR function is embedded into any communication nodes for capturing, filtering, storing, selecting, calculating, and redirecting requests in network traffic. The maximum throughput of the developed SoR is 1.12 Gbps, and the size of its packet buffer is approximately 100 MB. To confirm the feasibility of the proposed service-oriented architecture for smart grid communications, the performance of a power grid model is evaluated using MATLAB/Simulink and SimPowerSystems Toolbox. © 2013 IEEE.

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SoR-based programmable network for future software-defined network

Kenichi Takagiwa, Shinichi Ishida, Hiroaki Nishi

Proceedings - International Computer Software and Applications Conference （IEEE） 165 - 166 2013年

査読有り, ISSN 0730-3157

The Future Internet architecture would be advanced and flexible depending on service requirements by program. The concept of Software-Defined Network (SDN) has a possibility to enable innovation while hiding much of the complexity on the networking design. SDN is mainly used by OpenFlow in real scenario, which can use up to layer-4. In this paper, we propose SDN which consider up to layer-7. To maintain flexible network and to get maximum benefit from networks, Service-oriented Router (SoR) was introduced. A SoR enables layer-2 to layer-7 information to be captured, analyzed, and stored and has a high-throughput database(DB) and is able to analyze all transactions on its interfaces. In addition, SoRs can provide APIs to access stored contents in order to enrich services. In our system, we make network programmable by considering layer-7 information, which can not be captured by using OpenFlow method. This feature will make future SDN more effective and convenient. © 2013 IEEE.

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Service-oriented router-based CDN system: An sor-based CDN infrastructure implementation on a real network environment

Janaka Wijekoon, Shinichi Ishida, Erwin Harahap, Hiroaki Nishi

Proceedings - International Computer Software and Applications Conference （IEEE） 742 - 747 2013年

査読有り, ISSN 0730-3157

Internet users are constantly demanding faster and higher quality services from their internet service providers. Therefore, for fast data delivery of such applications, Content Delivery Networks (CDNs) have been introduced. Most CDN providers use Domain Name Resolution (DNS) based request routing (RR) methods to find the nearest server for a particular client and it has both advantages and disadvantages. Importantly, disadvantages result high latencies of data delivery and network congestions. To maintain rich information in the Internet and to shift the current Internet infrastructure to an information-based open environment platform, Service-oriented Routers (SoRs) have been introduced. An SoR has a high-Throughput database and it is able to analyze all transactions on its interfaces. Therefore, we have used the basic functionalities of the SoR to diminish disadvantages of the DNS-based RR methods. Proposed system is independent from DNS-based RR and we have conducted experiments based on content-centric RR using the SoR basic functionalities and successfully evaluated and compared both of the round trip time (RTT) and the packet inter arrival time. Our results indicated that SoR-based method can reduce upto 40-50% latency in both connection initiation time and content migration time in-between servers. © 2013 IEEE.

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Service-oriented router simulation module implementation in NS2 simulator

Janaka Wijekoon, Erwin Harahap, Hiroaki Nishi

Procedia Computer Science （ELSEVIER SCIENCE BV） 19 478 - 485 2013年

査読有り, ISSN 1877-0509

The Service-oriented Router (SoR) is a router for next generation networks. This router has a high-throughput database and it has the capability to snoop all transaction in its interfaces. The SoR also provides an API which can provide stored content in order to enrich services. The SoR has the potential to shift the current Internet infrastructure to an information-based, open innovation platform. In order to evaluate the efficiency of SoR-based applications and services, a specific simulator is required. Though the NS2 simulator does not simulate payload handling, it is a well-known network simulator and there are many resources available for evaluations. In this research, we implemented three new modules for the NS2 platform to test the concepts of an SoR, an SoR agent, a packet container and a packet analyzer. The SoR agent can interconnect the application and physical layers of the NS2 module with an additional function that can handle user data as a real payload and attaches it to the IP packet. The packet container is an improved NS2 module that can attach user data and trace information. A successful simulation has been performed for end-to-end packet transfer with a 0.02s packet delivery delay compared to typical NS2 packet delivery. The NS2 router has been enhanced for packet stream analyzing and content centric packet re-routing. Content centric packet re-routing has been achieved with 0.01s additional delay for end-to-end packet delivery. Result shows that Deep Packet Inspection and content centric networking in an SoR-based network can be achieved. © 2013 The Authors. Published by Elsevier B.V.

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Router-based request redirection management for a next-generation content distribution network

Erwin Harahap, Janaka Wijekoon, Rajitha Tennekoon, Fumito Yamaguchi, Hiroaki Nishi

2013 IEEE Globecom Workshops, GC Wkshps 2013 （IEEE） 1007 - 1012 2013年

査読有り, ISSN 2166-0069

The increase in the amount of digital data transferred between contents Servers and Clients in a network causes problems created by congestion when downloading big web files, streaming media, etc. Content Delivery Networks (CDNs) are introduced to overcome such problems by redirecting the Clients request to the nearest Server. However, as the number of people accessing Internet increases rapidly, the performance of CDN is reduced, resulting in network congestion at times. To solve these problems, we propose an architecture in which a new management method is employed to redirect the Clients request using a content-based Router called the Service-oriented Router (SoR). This method is more effective than the currently implemented, traditional DNS-based request redirection (RR). The SoR is a special router that can perform a deep packet inspection of the packet streams. Our experiments were based on analytical modeling as well as test bed experiments, and they confirmed that the response time in the Router-based RR was less than that in the DNS-based RR by 23.3%. In addition, our test bed experiments showed that the RTT in the Router-based RR is less than that in the DNS-based RR by 7.7%. © 2013 IEEE.

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Real-time METs estimation for effective indoor amenity control in HEMS

Minako Ito, Hiroaki Nishi

IEEE International Symposium on Industrial Electronics （IEEE） 1 - 6 2013年

In the regulation of heating, ventilation, and air conditioning (HVAC) for a peak cut or peak leveling control of electric power consumption, the amenity of the living environment should be considered. In the existing method, the metabolic equivalent (MET) value is not considered because of the substantial measurement costs and because a special infrastructure is required for both measuring the value by the MET meter and for communicating with the HVAC control server in the home energy management system (HEMS) or building EMS (BEMS). This paper proposes a method for measuring the MET value on a mobile device for accurately calculating the predicted mean vote (PMV). This method is designed as an iPod touch or iPhone application. The application has sufficiently reduced energy consumption for use as a mobile device application and is sufficiently accurate for use as an HVAC control. The availability and usefulness of both the designed application and the proposed MET measuring method is experimentally confirmed, and the reduction in energy consumption is estimated using an actual HEMS. © 2013 IEEE.

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Hardware-based hash functions for network applications

Fumito Yamaguchi, Hiroaki Nishi

IEEE International Conference on Networks, ICON （IEEE） 1 - 6 2013年

査読有り, ISSN 1556-6463

For rich network services, it is indispensable to reconstruct TCP stream in the middle of the network. In this reconstruction function, managing a large number of streams is a crucial as an embedded hardware for achieving high-throughput processing. In this case, hashing is a well-used solution as an ID key of TCP streams. Since CRC hashes have simple tree structure of XOR logics and are perfectly composed of combination logics, they can easily be hardware implemented and enables low-latency calculation of the hash values. Therefore, CRC hash has been used in network applications where low-latency and high speed operations are necessary. Some of their usages include data identification, load balancing, encryption, and checksum. Although CRC hashes may be well suited for hardware implementation, it is not the top choice when collision rates and distribution of hash values are considered. For some network workloads, CRC hashing shows very uneven distribution of hash values and can lead to decrease in the overall performance of network systems. In this study, two hashes, Jenkins hash and MurmurHash, are implemented on a FPGA as TCP connection manager and evaluated for their aptitude for hashing used in hardware-based network applications. © 2013 IEEE.

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GPU-based multi-stream analyzer on application layer for service-oriented router

Kazumasa Ikeuchi, Janaka Wijekoon, Shinichi Ishida, Hiroaki Nishi

Proceedings - IEEE 7th International Symposium on Embedded Multicore/Manycore System-on-Chip, MCSoC 2013 （IEEE Computer Society） 171 - 176 2013年

査読有り

A service-oriented router (SoR) is a new router architecture that provides rich application-layer services to Internet users by extracting information from network traffic. SoR performs stream reconstruction and selection using string matching. After on-the-fly reconstruction of stream data, SoR extracts the required information using a software-based character string analyzer. For wire-rate string matching and for design flexibility, a software-based string-matching accelerator is required. A graphics processing unit (GPU) is a promising solution as a conventional cost-effective accelerator for use in a high-end router. Existing string-matching methods do not consider the multiple-stream processing and effective thread management required in a network application. We propose an accelerated string-matching method that is customized for a router and implemented a task controller that improves thread distribution depending on the status of core processes. © 2013 IEEE.

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環境快適性と消費電力量を考慮した家電制御最適化手法

中部知久, 西宏章

日本建築学会環境系論文集（日本建築学会） 77 （ 682 ） 1011 - 1019 2012年12月

ISSN 1348-0685

In the DSM (Demand Side Management) system, a control method for controlling electric appliances in living space should take account of environmental amenity. This paper focuses on a trade-off relationship between power consumption and environmental amenity. We proposed a new method to evaluate this relationship, and it enables to optimize the environmental amenity by air conditioning under the restriction of total power consumption. The proposed method was evaluated by using real environment. This evaluation shows the proposed could improve up to 27.4% in temporary summation of comfort index compared with an existing method.

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