研究者詳細 - 野林　大起

論文 - 野林　大起

分割表示 >> ／全件表示108 件中 1 - 108 件目

Adaptive Data Transmission Control for Spatio-temporal Data Retention over Crowds of Vehicles 査読有り国際誌

Nobayashi D., Goto I., Teshiba H., Tsukamoto K., Ikenaga T., Gerla M.

IEEE Transactions on Mobile Computing 21 ( 11 ) 3822 - 3835 2022年11月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

Some specific services for Internet of Things, such as real-time map and providing local weather information, depend strongly on geographical time and location. We refer to the data for such service as spatio-temporal data (STD). When STD is used in a query response system similar to conventional Internet services, users not only need to acquire data actively as required, they must also have functions for retrieving data available STD. Therefore, we propose an STD retention system that uses vehicles as information hubs (InfoHubs) for disseminating and retaining the data in a specific area. In our system, InfoHubs diffuse, maintain, and advertise STD over places and times where the STD are strongly dependent, thereby allowing users to receive such data passively within the specific area. Additionally, because STD are associated with a particular space, the system can reduce search costs. We also propose an adaptive transmission control method that each vehicle effectively operates its wireless resources autonomously and STD are retained and distributed efficiently. Finally, we evaluated our proposed method using simulations and clarified that our proposed system is capable of achieving a coverage rate of nearly 100% for STD while reducing the number of data transmissions compared to existing systems.

DOI： 10.1109/TMC.2021.3066438

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85103149527&origin=inward

P4-Based Buffer Management Method for Throughput Fairness Improvement with Different Congestion Control Contention 査読有り

Koshi Ono, Daiki Nobayashi, Takeshi Ikeanga

IEEE 43th International Conference on Consumer Electronics (ICCE 2025) 2025年01月

Multi-Dementional Feature Engineering for Reliable Detection Method of Vehicles with Location Information Errors in Spatio-Temporal Data Retention System 査読有り

Tatsuya Takabe, Hiroshi Yamamoto, Daiki Nobayashi, Takeshi Ikenaga, Kazuya Tsukamoto

IEEE 43th International Conference on Consumer Electronics (ICCE 2025) 2025年01月

Experimental evaluation of downlink communication performance of IEEE 802.11ax wireless LAN: OFDM vs. OFDMA 査読有り国際誌

Oogami T., Tamura H., Nobayashi D., Tsukamoto K.

International Journal of Grid and Utility Computing 16 ( 1 ) 60 - 68 2025年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

Although Orthogonal Frequency Division Multiple Access (OFDMA), adopted in IEEE 802.11ax, allows an Access Point (AP) to communicate with multiple stations (STAs) simultaneously, the bandwidth of the Resource Unit allocated to each STA is inversely proportional to the number of STAs. In contrast, Orthogonal Frequency Division Multiplexing (OFDM) allows an AP/STA pair, determined by carrier-sense multiple access with collision avoidance, to dominate the entire bandwidth. However, the latency before packet transmission increases with the number of STAs. The number of STAs that want to communicate with an AP thus significantly impacts throughput under OFDM and OFDMA. Therefore, this study evaluates the communication performance for rich content and voice data when multiple STAs (up to five) are connected to an AP with OFDM or OFDMA by lab experiments. Through experimental results, we clarified which is more suitable, either OFDM or OFDMA, to improve the Quality of Experience (QoE) and throughput with the change in the number of STAs and application types of traffic.

DOI： 10.1504/IJGUC.2025.143883

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85215656450&origin=inward

Packet Scheduling Algorithm for Improving Fairness under Different Congestion Control Contention using P4 査読有り

Koshi Ono, Daiki Nobayashi, Takeshi Ikeanga

Proc. of IEICE 2024 International Conference on Emerging Technologies for Communications, (ICETC2024) 2024年11月

Performance Improvement of Large Spatio-Temporal Data With Encoded Packets 査読有り

Naoki Tanaka, Daiki Nobayashi, Kazuya Tsukamoto, Takeshi Ikenaga

Proc. of IEICE 2024 International Conference on Emerging Technologies for Communications, (ICETC2024) 2024年11月

Data Collection Method for MEC integrated with STD Retention System on Floating-CPS Platform 査読有り

Meiya Tanaka, Daiki Nobayashi, Kazuya Tsukamoto, Takeshi Ikenaga, Shu Sekigawa, Myung Lee

Proc. of IEICE 2024 International Conference on Emerging Technologies for Communications, (ICETC2024) 2024年11月

Malicious Behavior Detection Method based on Feature Extraction of Malware DNS Traffic Data 査読有り

Toshiki Koga, Daiki Nobayashi, Takeshi Ikenaga

Proc. of IEICE 2024 International Conference on Emerging Technologies for Communications, (ICETC2024) 2024年11月

Efficient Frequency Bandwidth Limitation for Wireless-Based Ultrasonic Data Collection Systems 査読有り国際誌

Shigyo Rio, Nobayashi Daiki, Tsukamoto Kazuya, Mizumachi Mitsunori, Ikenaga Takeshi

信号処理 ( 信号処理学会 ) 28 ( 4 ) 129 - 132 2024年07月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

<p> IoT-based acoustic data collection systems have been proposed for detecting anomalies in mechanical equipment. However, traditional systems using audible sound do not work well due to interference from various sound sources. To solve this problem, we have previously proposed an ultrasonic data collection system, but the clear and high-quality sound required for anomaly detection results in an increase in data volume. This paper proposes a method for extracting only the necessary frequency band based on the periodicity of the target signal, aiming to reduce the amount of data. Our experiments demonstrate that the proposed method efficiently determines the appropriate frequency band in which the characteristics of the target equipment appear, thereby enabling the amount of data to be reduced by more than 45%.</p>

DOI： 10.2299/jsp.28.129

その他リンク： https://www.jstage.jst.go.jp/article/jsp/28/4/28_129/_pdf

Fairness improvement method using explicit congestion notification for QUIC 査読有り国際誌

Uchida Nobuhiro, Nobayashi Daiki, Cavendish Dirceu, Ikenaga Takeshi

IEICE Communications Express ( 一般社団法人電子情報通信学会 ) 13 ( 6 ) 222 - 226 2024年06月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

<p>QUIC is a transport protocol that adds congestion control, retransmission control, and TLS to UDP. QUIC can use the same congestion control algorithms as TCP. In previous work, we have shown that communication performance becomes unfair concerning the buffer size of the shared bottleneck link of two flows, one using CUBIC and the other BBR congestion control algorithms within QUIC. In this study, we improve the communication fairness performance at different bottleneck link buffer sizes by using Round Trip Time (RTT) and Explicit Congestion Notification (ECN) to regulate congestion control aggressiveness when CUBIC and BBR compete within QUIC through actual experiments.</p>

DOI： 10.23919/comex.2024xbl0014

その他リンク： http://xplorestaging.ieee.org/ielx7/10250155/10547173/10494945.pdf?arnumber=10494945

Performance Evaluation of Multipath TCP Video Streaming on LEO Satellite/Cellular Networks 査読有り

Yosuke Komatsu, Dirceu Cavendish, Daiki Nobayashi, Takeshi Ikenaga

The Sixteenth International Conference on Evolving Internet (INTERNET 2024) 2024年03月

An Efficient Method of Frequency Bandwidth Limitation for Wireless-based Ultrasonic Data Collection System 査読有り

Rio Shigyo, Daiki Nobayashi, Kazuya Tsukamoto, Mitsunori Mizumachi, Takeshi Ikenaga

2024 RISP International Workshop on Nonlinear Circuits, Communications and Signal Processing 2024年03月

Performance Evaluation of Multipath TCP Video Streaming on LEO Satellite/Cellular Networks 査読有り

Yosuke Komatsu, Dirceu Cavendish, Daiki Nobayashi, Takeshi Ikenaga

The Sixteenth International Conference on Evolving Internet (INTERNET 2024) 2024年03月

An Efficient Method of Frequency Bandwidth Limitation for Wireless-based Ultrasonic Data Collection System 査読有り

Rio Shigyo, Daiki Nobayashi, Kazuya Tsukamoto, Mitsunori Mizumachi, Takeshi Ikenaga

2024 RISP International Workshop on Nonlinear Circuits, Communications and Signal Processing 2024年02月

Dynamic Transmission Parameter Settings Based on Data Transmission and Reception Performance for 920MHz LoRa Communication 査読有り

Tanaka R., Nobayashi D., Tsukamoto K., Ikenaga T., Sato G., Takizawa K.

Proceedings - IEEE Consumer Communications and Networking Conference, CCNC 1102 - 1103 2024年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

LPWA (Low Power Wide Area) is expected to be a communication technology suitable for the Internet of Things (loT) because of its features. Since LoRa communication has a trade-off between communication range and transmission rate, performance is inherently varied depending on the surrounding environment. Therefore, to achieve stable and efficient communication performance, it is necessary to set appropriate parameters for LoRa depending on the communication environment between the base station and the terminal. We here propose a method for dynamic control of parameter settings based on reception statistics of beacons. The effectiveness of the proposed method is evaluated from the real experiments.

DOI： 10.1109/CCNC51664.2024.10454734

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85189207920&origin=inward

Dynamic A-MPDU Adaptation Method for Airtime Fairness in Channel Bonding-Ready WLANs 査読有り国際誌

Tamura H., Nobayashi D., Kawahara K., Tsukamoto K.

IEEE Access 12 87954 - 87966 2024年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

Channel bonding is a technology that increases the transmission rates by bundling and using multiple continuous channels. However, its communication performance decreases over time because of the channel competition caused by nearby wireless LAN devices. Dynamic channel bonding (DCB) is projected to become mainstream based on efficient channel utilization, which can overcome this performance degradation even under severe competitive conditions. However, because the implementation of the DCB in actual hardware products and simulators is still in the preliminary stage, its performance has not been evaluated in detail. The performance of DCB has not been evaluated at the frame level with carrier-sense multiple access/collision avoidance (CSMA/CA) functions under diverse channel competition conditions. In this study, we employed a theoretical approach (2times M/M/1/K) based on the frame level to evaluate the performance of DCB with the CSMA/CA function. Furthermore, we implemented a channel bonding mechanism in the Scenargie simulator and verified its effectiveness by comparing the simulation results with theoretical results. The simulation results show that the DCB inevitably undergoes performance degradation owing to a performance anomaly caused by airtime unfairness. Therefore, we propose a dynamic A-MPDU adaptation method to achieve airtime fairness among the nearby wireless LANs. The proposed method can maximize throughput performance while achieving airtime fairness.

DOI： 10.1109/ACCESS.2024.3418434

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85197026498&origin=inward

Accuracy Improvement Method for Malicious Domain Detection Using Machine Learning 査読有り

Koga T., Nobayashi D., Ikenaga T.

Proceedings - IEEE Consumer Communications and Networking Conference, CCNC 1108 - 1109 2024年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

With the widespread Internet technologies, malware damage also spreads worldwide, making it necessary to address these issues urgently. In some cases, malware-infected terminals use the Domain Name System (DNS) when communicating with the Command and Control (C&C) servers to obtain information for attacks. The previous malware detection focuses on the DNS communication history of malware-infected terminals. However, this method has the problem of poor accuracy in detecting malicious domains when the analysis data is small. This paper proposes a malicious domain detection with the following improvements. The first improvement is adding information on response and time. The second improvement is shortening the query domain names to primary domain names. Further, the proposed method showed improvement in the experiment.

DOI： 10.1109/CCNC51664.2024.10454674

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85189209312&origin=inward

Packet Recovery Method with Redundant Packets for Large Spatio-Temporal Data Retention 査読有り

Tanaka N., Nobayashi D., Tsukamoto K., Ikenaga T.

Proceedings - IEEE Consumer Communications and Networking Conference, CCNC 1110 - 1111 2024年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Cyber Physical System (CPS) is a system that accumulates information from physical space, analyzes them in cyberspace, and then feeds back the results. We aim to realize a Floating Cyber Physical System (F-CPS), a regionally distributed CPS. We have proposed a large-capacity spatio-temporal data retention system for delivering data and function (application) in the F-CPS. In a previous work, we proposed a data completeness-aware transmission control and evaluated it by simulation. However, considering the movement of obstacles and fluctuation of radio waves in the real environment, packet loss occurs frequently. Thereby, the system may not be able to have complete data and may not function. In this paper, we proposed a method to recover missing data using redundant packets and evaluated its impact on the entire system by testing it with actual equipment.

DOI： 10.1109/CCNC51664.2024.10454686

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85189208289&origin=inward

Performance Evaluation of Spatio-temporal Data Retention System Supporting a Floating Cyber-physical System 招待有り査読有り国際誌

Nobayashi Daiki, Akashi Renju, Tsukamoto Kazuya, Ikenaga Takeshi, Lee Myung J.

Journal of Information Processing ( 一般社団法人情報処理学会 ) 32 ( 0 ) 566 - 574 2024年01月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

<p>We propose a floating cyber-physical system (F-CPS) as a novel platform for data distribution and application execution to realize a CPS. The F-CPS constructs a local-oriented and distributed CPS using devices with computing capability close to the user, such as smartphones, sensor devices, vehicles, and roadside units. This paper first provides an overview of the F-CPS and then discusses the challenges posed by the spatio-temporal retention system (STD-RS), a network technology for data distribution and maintenance in the local area of the F-CPS. To address the challenges associated the STD-RS, we propose adaptive data transmission control to effectively retain the STD in a certain area. Finally, we performed network simulations to demonstrate the effectiveness of the proposed adaptive method.</p>

DOI： 10.2197/ipsjjip.32.566

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85203607088&origin=inward

Experimental Evaluation for TCP/IP Communication Performance in Multi-Hop Private LoRa Network 査読有り

Aramaki E., Nobayashi D., Tsukamoto K., Ikenaga T., Sato G., Takizawa K.

IEEE Workshop on Local and Metropolitan Area Networks 7 - 8 2024年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Low-power wide-area (LPWA) is a major communicaiton technology used in the Internet of Things (Io'I'), Major sensor networks are constructed using original protocols specific to each LPWA standard and cannot communicate directly with devices connected to the Internet. To enhance the convenience of devices using LPWA, it is necessary to improve their interop-erability with Internet applications with TCP/IP. Previous study have enabled Single-hop TCP/IP communication over Private LoRa. In this study, we construct a multi-hop environment for TCP/IP communication over Private LoRa, and evaluate its performance using both UDP and TCP communication. Previous research has enabled one-to-one communication using UDP and TCP over a Private LoRa interface, an LPWA technology. This study leverages the characteristics of LPWA for ultra-Iong-distance transmission and implements TCP/IP communication in a multi-hop environment. This paper evaluates the performance of UDP and TCP on actual devices.

DOI： 10.1109/LANMAN61958.2024.10621878

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85201812478&origin=inward

Performance Evaluation of the Impact between IEEE 802.11ah and Private LoRa Using 920 MHz Band 査読有り

Takeuchi Y., Nobayashi D., Ikenaga T.

Proceedings - IEEE Consumer Communications and Networking Conference, CCNC 1104 - 1105 2024年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

IEEE 802.11ah (11ah) is a wireless LAN standard using the 920 MHz band and is expected to be used in the IoT field as one of the Low Power Wide Areas (LPWAs). Many LPWAs share the 920 MHz band and are characterized by low transmission rates but long-range communication. Therefore, there is a high possibility of contending communication in the real-world environment. In this study, we clarify the characteristics of contending communications between 11ah and LoRa according to evaluating the performance using real devices.

DOI： 10.1109/CCNC51664.2024.10454837

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85189199473&origin=inward

Poster: TCP Congestion Control based on Transmission Rate of Wireless LAN Interfaces 査読有り国際誌

Okada A., Nobayashi D., Ikenaga T.

Proceedings - International Conference on Network Protocols, ICNP 2024年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

TCP congestion control uses end-to-end delay and packet discard information to control the transmission rate. In the wireless LAN, there is a time lag between TCP congestion control and the transmission rate control of the wireless LAN interfaces, and there is no coordination between the respective controls. Thus, congestion control corresponding to the current state of the wireless network can be achieved by shortening this time lag. Therefore, this paper proposes a method to control the congestion window by detecting changes in the transmission rate of the wireless LAN interfaces. Our proposed method enables to control congestion windows size by using data link layer information, instead of using only transport layer information. This paper verified the effectiveness of the proposed method by network simulator ns-3.40.

DOI： 10.1109/ICNP61940.2024.10858575

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85218031359&origin=inward

Performance Evaluation of Dynamic Transmission Parameter Control Method for Mobile Terminal with 920 MHz LoRa Communication 査読有り国際誌

Tanaka R., Nobayashi D., Tsukamoto K., Ikenaga T., Sato G., Takizawa K.

2024 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing, PACRIM 2024 2024年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Low Power Wide Area (LPWA) is expected to be a communication technology suitable for the Internet of Things (IoT) due to its features, such as low power consumption, low cost, and long-distance transmission. Since LoRa communication has a trade-off between communication range and transmission rate, its communication performance is inherently varied depending on the surrounding environment. Therefore, in the previous study, we proposed a dynamic parameter control method based on beacon reception characteristics to fixed nodes to provide stable and efficient communication and evaluated its effectiveness. However, since the communication environment for mobile nodes is constantly changing, that method is challenging to contribute to performance improvement for mobile nodes. This paper proposes a dynamic transmission parameter control method for mobile terminal with LoRa communication. The effectiveness of the proposed method is evaluated from the real experiments.

DOI： 10.1109/PACRIM61180.2024.10690200

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85206804129&origin=inward

Multipath TCP Video Streaming Hand-Offs on LEO Satellite/5G Cellular Networks 査読有り国際誌

Komatsu Y., Cavendish D., Nobayashi D., Ikenaga T.

2024 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing, PACRIM 2024 2024年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Video streaming makes most of Internet traffic nowadays, being transported over Hypertext Transfer Protocol/Transmission Control Protocol (HTTP/TCP). Being the pre-dominant transport protocol, TCP stack performance in transporting video streams has become paramount, specially with regard to MultiPath Transport Control Protocol (MPTCP) innovation and multiple client device interfaces currently available. Recently, Low Orbit Satellite networks have become available as a way to cover remote locations where cellular coverage is spotty at best with Internet access. In this paper, we evaluate video streaming hand-off performance via cellular and LEO links. Such scenario is commonplace in geographical areas where cellular communication is unreliable, such as disaster and conflict torn situations. We provide an extensive analysis of Bottleneck Bandwidth and Round-trip propagation time (BBR) TCP variant, as well as CUBIC when handing off video streams between terrestrial cellular network (5G) and LEO (Starlink) access networks. We use network performance level, as well video quality level metrics to characterize quality of video streaming over TCP variants.

DOI： 10.1109/PACRIM61180.2024.10690202

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85206836877&origin=inward

MEC Collaborative Function Retention System Using WebAssembly for Floating-CPS 査読有り国際誌

Tanaka M., Nobayashi D., Tsukamoto K., Ikenaga T., Sekigawa S., Lee M.

2024 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing, PACRIM 2024 2024年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

To promote local production and consumption of Spatio-Temporal Data (STD), we have proposed a Floating Cyber-Physical System (F-CPS) that retains STD and functions (applications) to process and use the STD within a specific area. The F-CPS designed the functions to execute common applications on various types of devices, aiming to accelerate the effective use of STDs. Therefore, the function distributed within the area should be small, and an execution platform for the function does not depend on hardware and operating systems. Furthermore, there is a need for a system to recognize available functions to new users entering the area and deliver them appropriately. In this paper, we propose (1) a compact and portable application execution platform using WebAssembly, and (2) a function Retention System based on the MEC collaborative application delivery method. We evaluate the process of the application execution platform and delivery method in our proposed system using actual equipment. The result of the verification revealed that even when multiple devices retrieve an application simultaneously, the execution of the application could be completed within 2 seconds.

DOI： 10.1109/PACRIM61180.2024.10690196

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85206813965&origin=inward

In-Orbit Performance of LoRa for Internet of Things Communication on MicroOrbiter-1 Satellite 査読有り

Khamsah N.M.N., Moumni F., Nobayashi D., Ikenaga T., Cho M.

COMNETSAT 2024 - IEEE International Conference on Communication, Networks and Satellite 48 - 54 2024年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

The integration of Internet of Things (IoT) technology with satellite communications has reformed global connectivity, especially in remote regions that lack terrestrial infrastructure. Recent advancements in optimizing LoRa parameters for satellite-based IoT communications have boosted research in this field. Building on this foundation, the MicroOrbiter-1 satellite developed by MicroOrbiter Inc. in collaboration with the Kyushu Institute of Technology (Kyutech) enhances LoRa-based IoT capabilities in a 1U CubeSat platform. This paper presents the in-orbit performance evaluation of the MicroOrbiter-1 satellite's LoRa-based communication system on the 920 MHz frequency band with three Ground Sensor Terminals (GST) located in Kyutech (Japan), Rancabungur (Indonesia) and Vermont (USA). Key performance metrics such as Received Signal Strength Indicator (RSSI), Spreading Factor, and transmission errors, were analyzed across these locations. The results demonstrated the range of -112 dBm to -127 dBm signal strength for successful communication at low spreading factors. Temporal analysis was conducted using the System Tool Kit to categorize the data received from each terminal. While facing the challenges of power limitation and the lack of an attitude control determination system, the findings in the in-orbit performance analysis of the MicroOrbiter-1 satellite provide valuable insights for optimizing LoRa communication for future satellite missions, especially for CubeSats.

DOI： 10.1109/COMNETSAT63286.2024.10862081

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85218488615&origin=inward

Fairness Improvement of Different TCP Congestion Control Algorithms Using P4 Programmable Data Plane 査読有り国際誌

Ono K., Nobayashi D., Ikenaga T.

2024 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing, PACRIM 2024 2024年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

A wide variety of congestion control algorithms have been developed for the transport protocol of TCP/IP. A related study revealed that the communication performance becomes unfair depending on the buffer length of switches or routers in the end-to-end path when communication flows using CUBIC TCP and Bottleneck Bandwidth and Round-trip propagation time (BBR) compete with each other. Therefore, we propose the fairness improvement method between different types of congestion control in the programmable network by using P4 programming. The proposed method provides multiple queues to each congestion control in the switches or the routers for relaying. The proposed method then assigns incoming TCP flows to those queues for each congestion control algorithm. The congestion control algorithm is determined by P4, which implements a programmable data plane. Three types of packet scheduling are used to ensure fairness when sending packets. We evaluate the effectiveness of the proposed method using the network emulator 'mininet' and the communication performance when the queue length of the relaying switch.

DOI： 10.1109/PACRIM61180.2024.10690198

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85206838678&origin=inward

Frequency Bandwidth Limitation Method by Autocorrelation for Ultrasonic Data Collection System 査読有り

Rio Shigyo, Daiki Nobayashi, Kazuya Tsukamoto, Mitsunori Mizumachi, Takeshi Ikenaga

Proc. of IEICE 2023 International Conference on Emerging Technologies for Communications, (ICETC2023) 2023年11月

Complementary Data Diffusion Method for Quick Retention of Large SpatioTemporal Data 査読有り

Renju Akashi, Daiki Nobayashi, Kazuya Tsukamoto, Takeshi Ikenaga and Myung Lee

Proc. of IEICE 2023 International Conference on Emerging Technologies for Communications, (ICETC2023) 2023年11月

Experimental Evaluation of Transmission Control Method Based on Received Signal Strength for Spatio-Temporal Data Retention 査読有り

Renju Akashi, Daiki Nobayashi, Kazuya Tsukamoto, Takeshi Ikenaga and Myung Lee

Proc. of the IEEE 47th Annual International Computer, Software and Applications Conference (COMPSAC 2023) 2023年06月

Improvement of TCP Performance based on Characteristics of Private LoRa Interface 査読有り

Jumpei Sakamoto, Daiki Nobayashi, Kazuya Tsukamoto, Takeshi Ikenaga, Goshi Sato and Kenichi Takizawa

Proc. of the IEEE 47th Annual International Computer, Software and Applications Conference (COMPSAC 2023) 2023年06月

BBR Performance over Variable Delay Paths on Multipath TCP Video Streaming 査読有り

Masayoshi Kondo, Dirceu Cavendish, Daiki Nobayashi, Takeshi Ikenaga

The Fifteenth International Conference on Evolving Internet (INTERNET 2023) 2023年03月

Performance Evaluation on the Impact of Bottleneck Link Buffer Size under Different Congestion Control Algorithm Competition in QUIC 査読有り

Uchida N., Nobayashi D., Ikenaga T., Cavendish D.

Proceedings - IEEE Consumer Communications and Networking Conference, CCNC 2023-January 714 - 715 2023年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

QUIC is a secure, general-purpose transport protocol using congestion and retransmission controls on User Datagram Protocol (UDP). QUIC can use the same congestion control algorithms as Transmission Control Protocol (TCP). Thus, when communication between multiple terminals using QUIC competes, the performance of each terminal depends on the congestion control algorithm adopted by the terminal. In related works, the communication performance was evaluated by simulation when both CUBIC and BBR flows competed in TCP, and the results showed that each communication performance became unfair with the buffer size of the shared bottleneck link. In this study, we verify the communication performance at different bottleneck link buffer sizes when BBR and CUBIC compete through actual experiments.

DOI： 10.1109/CCNC51644.2023.10060682

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85150629349&origin=inward

Location-Based Autonomous Transmission Control Method for Spatio-Temporal Data Retention System 査読有り

Nobayashi D., Tsukamoto K., Ikenaga T., Lee M.

Lecture Notes in Networks and Systems 570 LNNS 224 - 235 2023年01月

担当区分：筆頭著者,　責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

With the development and spread of IoT technology, various devices have been connected to networks. Some data generated from IoT devices depends on geographical location and time (Spatio-Temporal Data). The realization of an architecture for “local production and consumption of STDs” can contribute to location-dependent applications, and therefore we have proposed the STD retention system with vehicles. In our previous study, the vehicle controlled the data transmission probability according to the density of the neighboring vehicles in order to reduce the data transmissions. However, since this method requires all vehicles to transmit beacons, it suffers from the excessive beacon collision when the vehicle density becomes high. In this paper, we propose a data transmission control method that realizes STD retention without transmitting beacons. Our simulation results using Luxembourg model demonstrates that the proposed method can achieve high coverage rate while decreasing the number of data transmissions compared with the existing transmission method based on transmission probability control in real environments.

DOI： 10.1007/978-3-031-20029-8_22

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Effective Data-Sharing Method for Multiple ICR Management in Autonomous Distributed Control Systems 査読有り

Kawano T., Nobayashi D., Ikenaga T.

Lecture Notes in Networks and Systems 492 239 - 248 2023年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Industrial carrier robots (ICRs), which are designed to deliver packages to designated destinations automatically in automated and semi-automated facilities, can potentially contribute to resolving labor shortages and improving productivity. Conventional ICRs operate within a centralized system in which a remote server manages both general task assignments and collision avoidance. However, such systems entail significant infrastructure maintenance costs. This paper focuses on autonomous operations and autonomous distributed control methods in which ICRs first share task and location information, and then distribute upcoming tasks among themselves based on that shared information. However, when each ICR is required to communicate with all the other ICRs in a distributed system, the number of wireless communications will increase with the number of system ICRs, thereby wasting wireless communication resources. In this paper, we propose a method that reduces wireless communication loads by using a sink node to streamline communication, and then presents simulation evaluation results that show it can effectively achieve autonomous distributed control in ICR systems.

DOI： 10.1007/978-981-19-3679-1_18

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85142680450&origin=inward

Complementary Data Transmission Control with Collision Avoidance for Efficient Retention of Large-size Spatio-Temporal Data 査読有り

Kaneyasu H., Nobayashi D., Tsukamoto K., Ikenaga T., Lee M.

Proceedings - IEEE Consumer Communications and Networking Conference, CCNC 2023-January 710 - 711 2023年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Spatio-temporal aware IoT applications need to deliver the Spatio-Temporal Data (STD), which depends on geographic location and time, to the users in real-time. We have proposed the STD retention system using crowds of vehicles to promote the immediate distribution and utilization of STDs in geographical proximity to the user. However, when the system retains a Large-size STD (LSTD) consisting of multiple packets such as videos and photos, the packet loss due to channel collisions should be suppressed for effective retention of an LSTD. In this paper, we propose a complementary data transmission control method with collision avoidance for LSTD retention and clarify the effectiveness of our proposed method by simulation.

DOI： 10.1109/CCNC51644.2023.10060769

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A Reliability Audit Mechanism based on Multi-layered Blockchain for Spatio-Temporal Data Retention System 査読有り

Ueda J., Tsukamoto K., Yamamoto H., Nobayashi D., Ikenaga T., Lee M.

Proceedings - IEEE Consumer Communications and Networking Conference, CCNC 2023-January 939 - 940 2023年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

IoT data includes Spatio-temporal data (STD) that is needed only at a specific time and place. In our previous research, we have proposed the STD data retention system (STD-RS), aiming to construct a novel architecture for STD distributing in a retention area by vehicles. However, since vehicles may distribute the STD in unexpected locations due to GPS errors or malicious behavior in a real environment. Therefore, we propose a reliability audit mechanism based on multi-layered blockchain managing and analyzing the history of STD distribution and vehicles' behavior in each retention area. Through simulation experiment, we demonstrated that our mechanism detects the malfunction of STD-RS effectively.

DOI： 10.1109/CCNC51644.2023.10059819

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Improvement of TCP Performance based on Characteristics of Private LoRa Interface 査読有り

Sakamoto J., Nobayashi D., Tsukamoto K., Ikenaga T., Sato G., Takizawa K.

Proceedings - International Computer Software and Applications Conference 2023-June 998 - 999 2023年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Low-power wide-area (LPWA) is a major communication technology used in the Internet of Things (IoT). However, since LPWA does not conform to the TCP/IP protocol stack and employs its own unique protocol, sensors equipped with LPWA I/F face difficulty when connecting directly to the Internet. In a previous study, to extend general TCP/IP communication on LPWA networks, we constructed a TCP/IP network over Private LoRa, but it was found that TCP communication performance using LoRa devices was significantly degraded due to the characteristics of LPWA such as the low transmission rate. In the present study, to improve the performance of TCP communication using the Private LoRa interface, we propose a transmission control method that avoids collisions by modifying the advertised window size on IP2LoRa and demonstrate the effectiveness of the proposed method using TCP flow analysis.

DOI： 10.1109/COMPSAC57700.2023.00145

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Experimental Evaluation of Transmission Control Method based on Received Signal Strength for Spatio-Temporal Data Retention 査読有り

Akashi R., Nobayashi D., Tsukamoto K., Ikenaga T., Lee M.

Proceedings - International Computer Software and Applications Conference 2023-June 1006 - 1007 2023年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

With the development and spread of IoT technology, the number of devices connected to the Internet is increasing. Some data generated by IoT devices include spatio-temporal data (STD) that depends on the location and time of data generation. Therefore, we have proposed the STD retention system (STD-RS) using vehicles as a network infrastructure for local production and consumption of STD. This paper proposes a transmission control method that can mitigate the fluctuation of RSS due to the influence of obstacles in the real environment and evaluates its effectiveness through experiments on actual devices.

DOI： 10.1109/COMPSAC57700.2023.00149

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Poster: Fairness Improvement Method Using ECNs with Different Congestion Control Algorithms within QUIC 査読有り国際誌

Uchida N., Nobayashi D., Cavendish D., Ikenaga T.

Proceedings - International Conference on Network Protocols, ICNP 2023年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

QUIC is a transport protocol that adds congestion control, retransmission control, and TLS to UDP. QUIC can use the same congestion control algorithms as TCP. In previous work, when both CUBIC and BBR flows compete within QUIC, we have shown that communication performance becomes unfair with respect to the buffer size of the shared bottleneck link. In this study, we improve the communication performance at different bottleneck link buffer sizes using Round Trip Time (RTT) and Explicit Congestion Notification (ECN) when CUBIC and BBR compete within QUIC through actual experiments.

DOI： 10.1109/ICNP59255.2023.10355640

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P4-based In-Network RL inference for Efficient Flow-Level Bandwidth Allocation 査読有り国際誌

Qadeer A., Lee M.J., Nobayashi D.

Proceedings - IEEE Global Communications Conference, GLOBECOM 1247 - 1252 2023年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Software-defined networking (SDN) has notably improved networks by providing Machine Learning-Powered programming capabilities at the control plane (CP), making it easier to dynamically manage the network resources according to varying traffic conditions. However, the geographically remote location of the CP from the data plane (DP) leads to significant round-trip delays in the order of milliseconds, which can ad-versely impact the performance of delay-sensitive and real-time traffic. To address this issue, this paper proposes a novel in-network reinforcement learning (RL) inference framework that extends programming capability from the CP to the DP for fine-grained control of network resources to meet the Quality of Service (QoS) demands of real-time applications. The in-network RL inference is achieved by adopting a match-action table mapping strategy in the DP and validating it through programming protocol-independent packet processors (P4). A P4 meter extern is utilized to allocate bandwidth to individual traffic flows based on their QoS requirements. Our proposed strategy achieves in-network RL inference at the line rate with negligible processing overhead while reducing packet loss rate and jitter by up to 92% and 57%, respectively, compared to the CP-based approach. Additionally, we evaluate the performance of our proposed bandwidth allocation framework using a state-of-the-art deep-deterministic policy gradient (DDPG)-based RL agent with a heuristic priority experience replay (hPER) technique. Our proposed DDPG agent achieves a faster convergence rate, higher reward, superior training stability, and up to 56 % reduction in operational cost compared to two alternative agents

DOI： 10.1109/GLOBECOM54140.2023.10437488

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Integrated Artificial Intelligence Technology for Mobility Load Balancing and Coverage Optimization 査読有り

Yi-We Ma, Chun-Yao Chang, Yi-Hao Tu, Jiann-Liang Chen, Kazuya Tsukamoto, Masahiro Shibata, Daiki Nobayashi, Takeshi Ikenaga

The 10th International Symposium on Applied Engineering and Sciences (2022) 2022年12月

Spatio-temporal Data Retention System for Floating Cyber Physical System 査読有り

Hotaka Kaneyasu, Daiki Nobayashi, Kazuya Tsukamoto, Takeshi Ikenaga, Myung Lee

The 10th International Symposium on Applied Engineering and Sciences (2022) 2022年12月

Implementation and Performance Evaluation of TCP/IP Communication over Private LoRa 査読有り

Sakamoto J., Nobayashi D., Tsukamoto K., Ikenaga T., Sato G., Takizawa K.

Proceedings - International Conference on Network Protocols, ICNP 2022-October 2022年10月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Low-power wide-area (LPWA) is a major communication technology used in the Internet of Things (IoT). However, since LPWA does not conform to the TCP/IP protocol stack and employs its own unique protocol, it is difficult for sensors equipped with LPWA I/F to connect to the Internet directly. In the present study, to realize general TCP/IP communication on LPWA networks, we construct a TCP/IP network over Private LoRa, and evaluate its communication performance. Moreover, we verify the feasibility of TCP/IP communication over LoRa by using a popular Internet application.

DOI： 10.1109/ICNP55882.2022.9940334

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Evaluation of MPTCP with BBR Performance on Wi-Fi/Cellular networks for Video Streaming 査読有り

Masayoshi Kondo, Dirceu Cavendish, Daiki Nobayashi, Takeshi Ikenaga

The Fourteenth International Conference on Evolving Internet (INTERNET 2022) 2022年05月

Data Completeness-aware Transmission Control for Large Spatio-Temporal Data Retention 査読有り国際誌

Kaneyasu H., Nobayashi D., Tsukamoto K., Ikenaga T., Lee M.

Digest of Technical Papers - IEEE International Conference on Consumer Electronics 2022-January 2022年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

With the development of IoT technology, various kinds of data are generated by IoT devices. Some of this data contains information on geographical location and time. We refer to such data as spatio-temporal data (STD). Since the 'local production and consumption' of STD is effective for location-dependent applications, we have proposed an STD retention system that utilizes vehicles as data sources. STD sources ranges from simple sensory data to large video data. However, since previous methods assumed to retain an STD consisting of only one packet, retention of large STD sources may suffer from frequent packet collisions due to the increase in the number of packet transmissions. In this paper, we propose a data completeness-aware transmission control mechanism for large STD retention. Our simulation results showed that the proposed scheme reduces channel collision by suppressing the forwarding of incomplete data, and achieved a nearly 100% coverage rate.

DOI： 10.1109/ICCE53296.2022.9730495

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Unknown Malicious Domain Detection based on DNS Query Analysis using Word2Vec 査読有り国際誌

Yamada H., Nobayashi D., Satoh A., Nakamura Y., Ikenaga T.

Proceedings - 2022 International Conference on Computational Science and Computational Intelligence, CSCI 2022 1096 - 1097 2022年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Malware infection of network user devices is a critical threat to users on the Internet. A major countermeasure against malware infection is a signature-type detection method that uses a blacklist to prevent communication with a Command and Control (C&C) server when the malware attempts a malicious attack. However, if the malicious domain name is unknown to the C&C server, it is difficult for this method to detect the malware. This paper focuses on the behavior of devices infected with malware. We propose a method for unknown malicious domain detection based on domain name system (DNS) query analysis using Word2Vec, a popular machine learning method. We then evaluate the effectiveness of our proposed method using an actual DNS Query log.

DOI： 10.1109/CSCI58124.2022.00196

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Study of Ultrasonic Data Collection System for Anomaly Detection for Mechanical Equipment 査読有り国際誌

Shigyo R., Nobayashi D., Tsukamoto K., Mizumachi M., Ikenaga T.

Proceedings - 2022 International Conference on Computational Science and Computational Intelligence, CSCI 2022 1237 - 1238 2022年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

loT-based acoustic data collection systems have been proposed for detecting anomalies in equipment. However, such systems do not work well in outdoor environments due to interference caused by various sound sources (e.g., wildlife sounds and traffic noise). Outdoor noise has unique frequency characteristics, with energy localized in the low-frequency domain. In contrast, mechanical equipment such as motors mainly generates harmonics, including ultrasonic components, during operation. This paper proposes a noise-robust ultrasonic data collection system for outdoor use. To reduce the size of collected data, which increases in proportion to the sampling frequency, the proposed system uses bandpass filtering and data compression.

DOI： 10.1109/CSCI58124.2022.00222

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Collision Avoidance Method for Broadcast Communication Over Multi-Hop HD-PLC Network 査読有り国際誌

Furuhama Y., Nobayashi D., Tsukamoto K., Ikenaga T.

Proceedings - 2022 International Conference on Computational Science and Computational Intelligence, CSCI 2022 1185 - 1186 2022年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

High Definition Power Line Communication (HD-PLC) is a communication technology that enables high-speed communications with a maximum PHY rate of 240 Mb/s using power lines. HD-PLC with multi-hop technology has been developed as a means of enabling long-distance communications. Multi-hop HD-PLC is expected to be used in BACnet for factory equipment and building management. However, the communication performance of BACnet is degraded by frequent data collisions caused by simultaneous broadcast message transmissions from multiple nodes. In this paper, we propose a transmission method to avoid collisions and reduce packet loss by using RTS/CTS control only in sections where collisions occur frequently. Simulation results show that the proposed method can reduce packet loss.

DOI： 10.1109/CSCI58124.2022.00212

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Development of Wireless Communication System for Reliable Acoustic Data Collection Toward Anomaly Detection on Mechanical Equipment 査読有り

Chinari Takano, Shinya Fujino, Daiki Nobayashi, Kazuya Tsukamoto, Mitsunori Mizumachi, Takeshi Ikenaga

The 2021 International Conference on Computational Science & Computational Intelligence (CSCI 2021) 2021年12月

Path Schedulers Performance on Cellular/Wi-Fi Multipath Video Streaming 査読有り国際誌

Masayoshi Kondo, Dirceu Cavendish, Daiki Nobayashi, Takeshi Ikenaga

The Thirteenth International Conference on Evolving Internet (INTERNET 2020) 2021年07月

An Approach for Identifying Malicious Domain Names Generated by Dictionary-Based DGA Bots 査読有り国際誌

Akihiro Satoh, Yutaka Nakamura, Yutaka Fukuda, Daiki Nobayashi, Takeshi Ikenaga

IEICE Transactions on Information Systems E104-D ( 5 ) 2021年05月

IEEE802.11ac準拠の機器におけるチャネルボンディング機能の性能評価査読有り

田村瞳, 藤井一樹, 野林大起, 塚本和也

情報処理学会デジタルプラクティス 2 ( 2 ) 99 - 113 2021年04月

Transmission Control Method for Data Retention Taking into Account the Low Vehicle Density Environments 査読有り

Goto I., Nobayashi D., Tsukamoto K., Ikenaga T., Lee M.

IEICE Transactions on Information and Systems ( 電子情報通信学会 ) E104.D ( 4 ) 508 - 512 2021年04月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

SUMMARY With the development and spread of Internet of Things (IoT) technology, various kinds of data are now being generated from IoT devices. Some data generated from IoT devices depend on geographical location and time, and we refer to them as spatio-temporal data (STD). Since the “locally produced and consumed” paradigm of STD use is effective for location-dependent applications, the authors have previously proposed a vehicle-based STD retention system. However, in low vehicle density environments, the data retention becomes difficult due to the decrease in the number of data transmissions in this method. In this paper, we propose a new data transmission control method for data retention in the low vehicle density environments.

DOI： 10.1587/TRANSINF.2020EDL8088

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Geolocation-centric information platform for resilient spatio-temporal content management 査読有り

Tsukamoto K., Tamura H., Taenaka Y., Nobayashi D., Yamamoto H., Ikenaga T., Lee M.

IEICE Transactions on Communications ( 電子情報通信学会 ) E104B ( 3 ) 199 - 209 2021年03月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

In IoT era, the growth of data variety is driven by cross-domain data fusion. In this paper, we advocate that “local production for local consumption (LPLC) paradigm” can be an innovative approach in cross-domain data fusion, and propose a new framework, geolocation-centric information platform (GCIP) that can produce and deliver diverse spatio-temporal content (STC). In the GCIP, (1) infrastructure-based geographic hierarchy edge network and (2) adhoc-based STC retention system are interplayed to provide both of geolocation-awareness and resiliency. Then, we discussed the concepts and the technical challenges of the GCIP. Finally, we implemented a proof-of-concepts of GCIP and demonstrated its efficacy through practical experiments on campus IPv6 network and simulation experiments.

DOI： 10.1587/transcom.2020NVI0003

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85102174288&origin=inward

Beacon-less autonomous transmission control method for spatio-temporal data retention 査読有り

Goto I., Nobayashi D., Tsukamoto K., Ikenaga T., Lee M.

Advances in Intelligent Systems and Computing 1263 AISC 503 - 513 2021年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

With the development and spread of Internet of Things (IoT) technology, the number of devices connected to the Internet is increasing, and various kinds of data are now being generated from IoT devices. Some data generated from IoT devices depends on geographical location and time. We refer to such data as spatio-temporal data (STD). Since the “local production and consumption” of STD is effective for location-dependent applications, we have proposed a STD retention system using vehicles equipped with storage modules, computing resources, and short-range wireless communication equipment. In this previous system, each vehicle controls the data transmission probability based on the neighboring vehicle density in order to achieve effective data retention. However, since the overhead of beacon messages required for estimation of the neighboring vehicle density becomes a critical problem with the increase in the number of vehicles, thereby preventing the effective data retention. In this paper, we propose a new data transmission control method to realize effective and reliable STD retention without beacon. Simulation results showed that our proposed scheme can achieve effective data retention.

DOI： 10.1007/978-3-030-57796-4_48

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85090094496&origin=inward

Efficient data diffusion and elimination control method for spatio-temporal data retention system 査読有り

Yamasaki S., Nobayashi D., Tsukamoto K., Ikenaga T., Lee M.J.

IEICE Transactions on Communications E104B ( 7 ) 805 - 816 2021年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

With the development and spread of Internet of Things technologies, various types of data for IoT applications can be generated anywhere and at any time. Among such data, there are data that depend heavily on generation time and location. We define these data as spatio-temporal data (STD). In previous studies, we proposed a STD retention system using vehicular networks to achieve the “Local production and consumption of STD” paradigm. The system can quickly provide STD for users within a specific location by retaining the STD within the area. However, this system does not take into account that each type of STD has different requirements for STD retention. In particular, the lifetime of STD and the diffusion time to the entire area directly influence the performance of STD retention. Therefore, we propose an efficient diffusion and elimination control method for retention based on the requirements of STD. The results of simulation evaluation demonstrated that the proposed method can satisfy the requirements of STD, while maintaining a high coverage rate in the area.

DOI： 10.1587/transcom.2020CQP0010

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85109677215&origin=inward

An approach for identifying malicious domain names generated by dictionary-based DGA bots 査読有り国際誌

Satoh A., Nakamura Y., Fukuda Y., Nobayashi D., Ikenaga T.

IEICE Transactions on Information and Systems ( 一般社団法人電子情報通信学会 ) E104.D ( 5 ) 669 - 672 2021年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

Computer networks are facing serious threats from the emergence of sophisticated new DGA bots. These DGA bots have their own dictionary, from which they concatenate words to dynamically generate domain names that are difficult to distinguish from human-generated domain names. In this letter, we propose an approach for identifying the callback communications of DGA bots based on relations among the words that constitute the character string of each domain name. Our evaluation indicates high performance, with a recall of 0.9977 and a precision of 0.9869.

DOI： 10.1587/transinf.2020NTL0001

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85106744554&origin=inward

Development of a Wireless Communication System for Reliable Acoustic Data Collection Toward Anomaly Detection in Mechanical Equipment 査読有り

Takano C., Fujino S., Nobayashi D., Tsukamoto K., Mizumachi M., Ikenaga T.

Proceedings - 2021 International Conference on Computational Science and Computational Intelligence, CSCI 2021 1544 - 1547 2021年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

With the recent proliferation of Internet of Things (IoT) devices that can send and receive data via wireless communication, we are able to monitor and operate these devices remotely. An example of an IoT system using wireless communication is a system for anomaly detection in mechanical equipment using acoustic data. In order to detect anomalies using acoustic data, continuous recording is essential, thereby increasing the data size. Although Wi-Fi networks provide high-capacity data transfer, performance degradation cannot be avoided due to reasons such as packet losses caused by collisions with data from other devices using the same frequency and the increase in distance between two communicating devices. In the present study, we developed a wireless communication system for reliable acoustic data collection for anomaly detection in mechanical equipment. First, as preliminary experiments, we investigated the communication characteristics for the transmission of large-size data by Wi-Fi in indoor and outdoor environments. The results indicated the communication performance was insufficient for transferring all recorded data handled by this system. Therefore, we developed a simple heuristic transmission timing control method and a method that can reduce the amount of transmission data in order to realize a stable acoustic data collection system. Finally, through demonstration experiments using mechanical equipment in the field, we verified the feasibility of the acoustic data collection system.

DOI： 10.1109/CSCI54926.2021.00300

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Development of Data Collection Platform for Running Cars by using 920MHz LoRa Communication in Urban Area 査読有り国際誌

Yasufumi Niwa, Daiki Nobayashi, Kazuya Tsukamoto, Takeshi Ikenag

2020 International Conference on Emerging Technologies for Communications (ICETC2020) 2020年12月

Development of Vehicle Management System using Location Data Collected by 920MHz LoRa 査読有り

Nobayashi D., Niwa Y., Tsukamoto K., Ikenaga T.

Proceedings - 2020 International Conference on Computational Science and Computational Intelligence, CSCI 2020 208 - 209 2020年12月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

The MaaS (Mobility as a Service), which collects, analyzes, and utilizes various data obtained various types of vehicles, is expected to solve various problems about traffic jams, autonomous driving, social community, etc. In this paper, we propose the vehicle management system at a low cost and effecivery using LoRa and Wi-Fi communication. Furthermore, we propose the application to estimate the arrival time assuming the use by a rental car company. The effectiveness of the proposed method is evaluated through demonstration experiments.

DOI： 10.1109/CSCI51800.2020.00042

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Adaptive Server and Path Switching for Content Delivery Networks 査読有り

Nishimuta H., Nobayashi D., Ikenaga T.

IEICE Transactions on Information and Systems ( 一般社団法人電子情報通信学会 ) E103D ( 11 ) 2389 - 2393 2020年11月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

© 2020 The Institute of Electronics, Information and Communication Engineers The communications quality of content delivery networks (CDNs), which are geographically distributed networks that have been optimized for content delivery, deteriorates when interflow congestion conditions are severe. Herein, we propose an adaptive server and path switching scheme that is based on the estimated acquisition throughput of each path. We also provide simulation results that show our proposed method can provide higher throughput performance levels than existing methods.

DOI： 10.1587/TRANSINF.2020EDL8045

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Handoff Characterization of Multipath Video Streaming 査読有り国際誌

Dirceu Cavendish, Kazuya Fujiwara, Shinichi Nagayama, Daiki Nobayashi, Takeshi Ikenaga

The Twelfth International Conference on Evolving Internet (INTERNET 2020) 2020年10月

Station-centric Access Point Selection Method for Heterogeneous Wi-Fi Environment 査読有り国際誌

Shohei Arakaki, Kazuya Tsukamoto, Daiki Nobayashi

IEEE Consumer Communications & Networking Conference (CCNC) 2020 2020年01月

On-demand transmission interval control method for spatio-temporal data retention 査読有り

Yamasaki S., Nobayashi D., Tsukamoto K., Ikenaga T., Lee M.

Advances in Intelligent Systems and Computing 1035 319 - 330 2020年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© Springer Nature Switzerland AG 2020. With the development and the spread of Internet of Things (IoT) technologies, various types of data are generated for IoT applications anywhere and anytime. We defined such data that depends heavily on generation time and location as Spatio-Temporal Data (STD). In the previous works, we have proposed the data retention system using vehicular networks to achieve the paradigm of “local production and consumption of STD.” The system can provide STDs quickly for users within a specific location by retaining the STD within the area. However, the system does not consider that each STD has different requirements for the data retention. In particular, the lifetime of the STD and the diffusion time to the whole area directly influence to the performance of data retention. Therefore, we propose a dynamic control of data transmission interval for the data retention system by considering the requirements. Through the simulation evaluation, we found that our proposed method can satisfy the requirements of STD and maintain a high coverage rate in the area.

DOI： 10.1007/978-3-030-29035-1_31

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Transmission control method to realize efficient data retention in low vehicle density environments 査読有り国際誌

Goto I., Nobayashi D., Tsukamoto K., Ikenaga T., Lee M.

Advances in Intelligent Systems and Computing 1035 2020年01月

Path Switching Schedulers for MPTCP Streaming Video 査読有り

Nagayama S., Cavendish D., Nobayashi D., Ikenaga T.

2019 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing, PACRIM 2019 - Proceedings 2019年08月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2019 IEEE. Recent developments on multipath transport protocols have allowed video streaming transmissions over multiple interfaces, improving session reliability as well as bandwidth performance. One important aspect of multipath transport is the selection of paths on a packet by packet basis. In particular, path switching may cause head of line blocking effects that may impact video rendering. In this work, we analyze the impact of path switching on multipath video streaming, and propose new path schedulers aimed at reducing path switching. We utilize network performance measures, as well as video quality metrics, to characterize new schedulers' performance improvements and interactions between network and application layers of video streams for various network scenarios.

DOI： 10.1109/PACRIM47961.2019.8985114

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Dynamic A-MPDU adaptation method for airtime fairness in channel bonding-ready WLANs 査読有り

Shimizu Y., Nobayashi D., Tamura H., Tsukamoto K.

2019 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing, PACRIM 2019 - Proceedings 2019年08月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2019 IEEE. Channel bonding is a technology to increase the transmission rate by bundling and using multiple continuous channels. However, the communication performance is likely to degrade frequently due to the channel competition caused by the rapid increase of the wireless LAN devices. Dynamic channel bonding is expected to become the mainstream in the future from the viewpoint of efficient channel utilization even under the severe competitive condition. However, since the implementation of the dynamic channel bonding to real PC and simulator is in the preliminary stage, the detailed performance investigation has not been carried out. None of existing studies examines the performance of the dynamic channel bonding at the frame level with CSMA/CA functions under the diverse channel competition condition. In this study, we first examine the performance of the dynamic channel bonding with CSMA/CA functions through theoretical approach (2 M/M/1/K) from the view point of frame level. In addition, we then implement the channel bonding mechanism into the Scenargie simulator and then verify its effectiveness through the comparison between simulation results and theoretical ones. Simulation results show that the dynamic channel bonding is suffering from the performance degradation due to the performance anomaly problem caused by the airtime unfairness, we thus propose a dynamic A-MPDU adaptation method. We showed that our proposed method can maximize throughput while achieving airtime fairness, irrespective of different patterns of channel competition.

DOI： 10.1109/PACRIM47961.2019.8985063

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85084344490&origin=inward

Conceptual experiment of geolocation-aware IoT data dissemination model 査読有り

Yuge K., Taenaka Y., Nobayashi D., Ikenaga T.

2019 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing, PACRIM 2019 - Proceedings 2019年08月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2019 IEEE. IoT devices are increasingly distributed around the world and have been digitizing physical things so far. However, a current IoT service is designed to be independent; it is not intended to conduct data collaboration with other IoT services. It must be important to be able to commonly use IoT data even from IoT devices managed for different services. To promote IoT data collaboration, we proposed a cross-domain data fusion platform on the basis of geographical proximity, called geocentric information platform (GCIP). Although GCIP enabled to collect and process data generated associated with geolocation of data generation, how to disseminate them should be still discussed. We can easily assume that some data summarization is preferable when data are used far away from the location of data generation. We also assume that there must be privacy and security issues in IoT data. That is why we propose a geolocation-aware IoT data dissemination model, which summarizes data due to the different distance between the location of the data source and the location of the destination. That is, as the distance becomes longer, the data is coarser. In this paper, we particularly focus on the behavior of the model and show the conceptual behavior by conducting experiments in a real environment.

DOI： 10.1109/PACRIM47961.2019.8985124

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Adaptive Server and Path Switching Scheme for Content Delivery Network 査読有り

Nishimuta H., Nobayashi D., Ikenaga T.

2019 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing, PACRIM 2019 - Proceedings 2019年08月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2019 IEEE. Due to increases in the number of providers providing large-capacity content, multimedia products such as videos, images, and music now account for most of the traffic flowing over the Internet, and content delivery networks (CDNs) that can guarantee the load distribution and communication quality of related products on the Internet are in use around the world. However, with current CDN technologies, it is difficult to change the server or the path between a user and a server after a user has established a connection with a distribution server. Therefore, when dealing with long duration CDN communications, the conventional path control and distribution server selection methods related to CDNs cannot respond flexibly to changes in communication quality once communication has started. In response to this issue, this paper proposes a path and server switching scheme based on the estimated available throughput of each path as a way to improve CDN communication performance. Furthermore, via network simulations, we show that our proposed method can provide higher throughput performance than existing methods.

DOI： 10.1109/PACRIM47961.2019.8985085

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85084344848&origin=inward

Managing Path Switching in Multipath Video Streaming 査読有り国際誌

Shinichi Nagayama, Dirceu Cavendish, Daiki Nobayashi, Takeshi Ikenaga

The Eleventh International Conference on Evolving Internet (INTERNET 2019), Jun. 2019. 2019年07月

A dynamic channel switching for rod-san 査読有り

Nobayashi D., Fukuda Y., Tsukamoto K., Ikenaga T.

IEICE Transactions on Information and Systems ( 電子情報通信学会 ) E102D ( 5 ) 920 - 931 2019年05月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

Copyright © 2019 The Institute of Electronics, Information and Communication Engineers. Wireless sensor and actuator networks (WSANs) are expected to become key technologies supporting machine-to-machine (M2M) communication in the Internet of things (IoT) era. However, sensors must be able to provide high demand response (DR) levels despite severely limited battery power. Therefore, as part of efforts to achieve a high DR, we are working on research and development related to radio-on-demand sensor and actuator networks (ROD-SANs). ROD-SAN nodes are equipped with wake-up receivers that allow all nodes to stay in sleep mode for a long period of time, and transmit only after the receiver receives a wake-up signal. In addition, sender nodes can direct the receiver nodes to switch communication channels because the wake-up signal also includes information on the channel to use for communication between each other. However, as the number of nodes utilizing the same channel increases, frequent packet collisions occur, thereby degrading response performance. To reduce packet collisions, we propose an own-channel-utilization based channel switching (OCS) scheme, which is a modification of the average-channel-utilization based switching (ACS) as our previous works. The OCS scheme decides whether or not to switch channels based on a probability value that considers not only average-channel utilization of nearby nodes but also own-channel utilization. This approach permits node switching to other channels by considering the overall utilization states of all channels. In this paper, based on simulations, we show that our scheme can improve the delivery ratio by approximately 15% rather than ACS scheme.

DOI： 10.1587/transinf.2018NTP0007

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Clustering malicious DNS queries for blacklist-based detection 査読有り

Satoh A., Nakamura Y., Nobayashi D., Sasai K., Kitagata G., Ikenaga T.

IEICE Transactions on Information and Systems E102D ( 7 ) 1404 - 1407 2019年01月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

Copyright © 2019 The Institute of Electronics, Information and Communication Engineers. Some of the most serious threats to network security involve malware. One common way to detect malware-infected machines in a network is by monitoring communications based on blacklists. However, such detection is problematic because (1) no blacklist is completely reliable, and (2) blacklists do not provide the sufficient evidence to allow administrators to determine the validity and accuracy of the detection results. In this paper, we propose a malicious DNS query clustering approach for blacklist-based detection. Unlike conventional classification, our cause-based classification can efficiently analyze malware communications, allowing infected machines in the network to be addressed swiftly.

DOI： 10.1587/transinf.2018EDL8211

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85069724844&origin=inward

Experimental performance evaluation of the collisions in lora communications 査読有り

Ishida Y., Nobayashi D., Ikenaga T.

Proceedings - 2018 International Conference on Computational Science and Computational Intelligence, CSCI 2018 1032 - 1035 2018年12月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2018 IEEE. With the development and spread of Internet of Things (IoT) technologies, various organizations in industry, academia, and government have begun collecting numerous types of data using sensor devices, which they then use to predict trends and identify potential problems with the services they provide. In the IoT, low power wide area (LPWA) networks can achieve low power consumption and provide a wide range of communication options that ensure constant service provision to deployed sensors. In particular, LoRa digital wireless communication technology, which has an open specification, uses an unlicensed band, and is inexpensive to install, is becoming increasingly popular and the number of sensors equipped with it is expected to grow in the future. However, since LoRa has insufficient specifications and verifications to resist channel contention within a heavily used frequency band, the performance of that technology is unclear when the number of sensors using the same frequency band increases. In this paper, we clarify the experimental performance of LoRa when multiple wireless communication nodes compete in different patterns.

DOI： 10.1109/CSCI46756.2018.00200

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85078516949&origin=inward

Path-selection method based on the available bandwidth of interfaces 査読有り

Ishida D., Nobayashi D., Ikenaga T.

Proceedings - 2018 International Conference on Computational Science and Computational Intelligence, CSCI 2018 815 - 818 2018年12月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2018 IEEE. The number of end devices equipped with multiple interfaces is increasing, owing to the spread of the Internet and the development of wireless communication technologies. Many applications work and communicate simultaneously in one end device. However, such end devices are difficult to utilize multiple interfaces and multiple paths effectively. Traditional transport protocols, such as Transmission Control Protocol (TCP) and User Datagram Protocol (UDP), support only single-path communication, so end device applications tend to use only single interface and path. Application' flows become unbalanced and compete; hence, their performance degrades. There are many related works using multiple interfaces and paths simultaneously, such as Multipath Transmission Control Protocol (MPTCP) and Multipath Internet Protocol (MPIP). However, in some cases, these methods cannot improve the communication performance because scheduling to multipath for concurrent applications is not effective. In this paper, we propose the path-selection method for each application based on the available bandwidth of interfaces of a device. This method can utilize network resources and improve the performance of all applications when many applications work and communicate on a device equipped with multiple interfaces. We evaluate this method using network simulations and show its usability.

DOI： 10.1109/CSCI46756.2018.00163

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Autonomous Data Transmission Control Based on Node Density for Multiple Spatio-Temporal Data Retention 査読有り

Nobayashi D., Tsukamoto K., Ikenaga T.

Proceedings of the 2018 IEEE 7th International Conference on Cloud Networking, CloudNet 2018 2018年11月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2018 IEEE. Although countless services can now be accessed via the Internet, some specific services such as local traffic conditions and limited-time sale advertisements are strongly dependent on geographical locations and times. Information of this type, which is commonly referred to as spatio-temporal data (STD), is not readily available online. Since the paradigm of local production and consumption of STDs can be effective for location-dependent applications, we previously proposed an STD data retention system that uses vehicular networks to create a mobile cloud. Unfortunately, effective data retention is difficult when multiple STDs exist in the same area because channel interference will result from the increased number of data transmissions. To resolve this issue, we herein propose an autonomous data transmission control method based on node density for multiple STD retention that facilitates a highly reliable coverage rate while limiting the individual data transmissions for each STD. Then, through simulations, we show that our proposed method is effective for simultaneously retaining multiple STDs.

DOI： 10.1109/CloudNet.2018.8549521

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85060258456&origin=inward

Experimental Investigation of Static Channel Bonding Performance in Competitive Environment

Kazuki Fujii, Hitomi Tamura, Daiki Nobayashi, Kazuya Tsukamoto

Technical Report of IEICE 2018年10月

Estimating the Randomness of Domain Names for DGA Bot Callbacks 査読有り

Akihiro Satoh, Yutaka Nakamura, Daiki Nobayashi, Takeshi Ikeanga

IEEE Communication Letters 22 ( 7 ) 2018年07月

Spatio-Temporal Data Retention System with MEC for Local Production and Consumption 査読有り

Daiki Nobayashi, Kazuya Tsukamoto, Takeshi Ikenaga, Mario Gerla

Proceedings - International Computer Software and Applications Conference 1 795 - 796 2018年06月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2018 IEEE. To facilitate local production and consumption (LPAC) of spatio-temporal data (STD) generated by Internet of Things (IoT) devices, we propose a STD retention system that works in collaboration with Mobile Edge Computing (MEC) infrastructure. In this paper, we will introduce the architecture of our proposed system and discuss its contributions and challenges.

DOI： 10.1109/COMPSAC.2018.00124

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85055445965&origin=inward

TCP State Driven MPTCP Packet Scheduling for Streaming Video 査読有り

Ryota Matsufuji, Shinichi Nagayama, Dirceu Cavendish, Daiki Nobayashi, Takeshi Ikenaga

The Nineth International Conference on Evolving Internet (INTERNET 2018) 2018年06月

Estimating the Randomness of Domain Names for DGA Bot Callbacks 査読有り

Akihiro Satoh, Yutaka Nakamura, Daiki Nobayashi, Takeshi Ikeanga,

IEEE Communications Letters 2018年04月

Multipath TCP path schedulers for streaming video 査読有り

Matsufuji R., Cavendish D., Kumazoe K., Nobayashi D., Ikenaga T.

2017 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing, PACRIM 2017 - Proceedings 2017-January 1 - 6 2017年11月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2017 IEEE. Modern internet traffic is heavily composed of some form of video communication. In addition, video streaming is slowly replacing regular phone connections. Given that most video transport utilizes Video over Hypertext Transfer Protocol/Transmission Control Protocol (HTTP/TCP), it is important to understand TCP performance in transporting video streams. Recently, multipath transport protocols have allowed video streaming over multiple paths to become a reality. In this paper, we investigate packet scheduling disciplines for injecting video stream packets into multiple paths at the video server. We study video streaming performance when subjected to these schedulers in conjunction with various TCP variants. We utilize network performance measures, as well as video quality metrics, to characterize the performance and interactions between network and application layers of video streams for various network scenarios.

DOI： 10.1109/PACRIM.2017.8121920

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85043452797&origin=inward

Performance Evaluation of 920 MHz band communication for underground infrastructure monitoring

Yuri Fujisaki, Daiki Nobayashi, Kazuya Tsukamoto, Takeshi Ikenaga

Technical Report of IEICE 2017年10月

VANET based Effective Data Transmission Control for Spatio-Temporal Data Retention System

Hiroki Teshiba, Daiki Nobayashi, Kazuya Tsukamoto, Takeshi Ikenaga

Technical Report of IEICE 2017年10月

Multipath TCP Packet Scheduling for Streaming Video 査読有り

Ryota Matsufuji, Dirceu Cavendish, Kazumi Kumazoe, Daiki Nobayashi, Takeshi Ikenaga

The Nineth International Conference on Evolving Internet (INTERNET 2017) 2017年07月

Field tests and indoor emulation of Real-Spatial Information Based Group Communication 査読有り

Nagata A., Nakamura K., Fuji H., Nobayashi D., Tsukamoto K., Ikenaga T.

2017 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2017 66 - 67 2017年05月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2017 IEEE. We proposed a novel scheme that combines information exchange and user social activities in real-time so that users can integrate their communications seamlessly with their daily lives. Called the Real-Spatial Information-Based Group Communication (r-Space) system, this scheme creates r-Space groups by considering personal and location information and enables users to share information within those groups. We developed a prototype system consisted of client application and control server and then conducted a field experiment in Nov. 2016. In PerCom 2017, the introduction of the experiment and its live demonstration will be exhibited.

DOI： 10.1109/PERCOMW.2017.7917524

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85019969814&origin=inward

Adaptive Data Transmission Control for Reliable and Efficient Spatio-Temporal 査読有り

Hiroki Teshiba, Daiki Nobayashi, Kazuya Tsukamoto, Takeshi Ikenaga

The Sixteenth International Conference on Networks (ICN2017) 2017年04月

Reliable Data Delivery Scheme for Real-Spatial Information Based Group Communication 査読有り

Daiki Nobayashi, Masaya Mitsuishi, Takeshi Ikenaga, Akira Nagata, Katsuichi Nakamura

IEICE Communications Express 6 ( 6 ) 393 - 398 2017年03月

Performance Characterization of Streaming Video over Multipath TCP 査読有り

Ryota Matsufuji, Dirceu Cavendish, Kazumi Kumazoe, Daiki Nobayashi, Takeshi Ikenaga, Yuji Oie

The Eighth International Conference on Evolving Internet (INTERNET 2016) 2016年11月

ROD無線LANにおける消費電力削減のための代理応答手法査読有り

野林大起, 福田豊, 池永全志

電子情報通信学会和文論文誌B J99-B ( 10 ) 908 - 910 2016年10月

Regional infohubs by vehicles: Balancing spatio-temporal coverage and network load 査読有り

Higuchi T., Onishi R., Altintas O., Nobayashi D., Ikenaga T., Tsukamoto K.

IoV-VoI 2016 - Proceedings of the 1st MobiHoc International Workshop on Internet of Vehicles and Vehicles of Internet 25 - 30 2016年07月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2016 ACM. The growing ubiquity of on-board wireless communication devices in vehicles is steadily opening up new possibilities of vehicular networks. In this paper, we design a framework to utilize radio-equipped cars as regional information hubs, which periodically disseminate public regional information (e.g., advertisements, travel tips, emergency info, etc.) over a designated geographical area in a city. The cars driving in the designated area repeatedly broadcast the data messages, allowing other drivers and pedestrians to passively obtain the information with their on-board wireless devices and/or smartphones. Although the idea follows a natural extension of the current capability of vehicular networks, vehicle densities in urban areas are typically highly non-uniform both in time and space, making it difficult to robustly disseminate data messages with minimal network load. We tackle this issue by introducing a probabilistic framework to intelligently adapt message dissemination strategy. Analyzing location broadcast messages, which are periodically exchanged among vehicles for safety applications, our protocol predicts future locations of neighboring radio-equipped vehicles and dynamically adjusts probability of message transmissions at each moment to suppress redundant network traffic. Simulation results show that our protocol can reduce the total amount of redundant message transmissions by up to 78%, while maintaining the spatio-temporal coverage of message dissemination.

DOI： 10.1145/2938681.2938688

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Radio on Demand Networks 技術による無線アクセスネットワークの省電力化招待有り査読有り

池永全志, 四方博之, 長谷川晃朗, 阿部憲一, 野林大起, 伊藤哲也

電子情報通信学会和文論文誌B J99-B ( 4 ) 261 - 274 2016年04月

Adaptive contention window control scheme for dense IEEE802.11 wireless LANs 査読有り

Ito R., Nobayashi D., Ikenaga T.

IEEE Pacific RIM Conference on Communications, Computers, and Signal Processing - Proceedings 2015-November 326 - 331 2015年11月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2015 IEEE. As portable information devices with a wireless local area network (LAN) interfaces, such as smartphones and tablet computers, become increasingly widespread, high station density and accompanying severe area throughput degradation are becoming more commonplace. One factor related to this situation is that the initial minimum contention windows size (CWmin) value in current Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) systems is set too low for the number of accessing stations. Because small CWmin values are unsuitable for high station densities, frame collisions become more commonplace and per-station communication performance decreases. In this paper, we assume that numerous stations are connected to a single access point (AP) and propose a media access control method for high station density network. In our proposed method, the AP periodically measures channel utilization and the number of stations that are transmitting frames to the AP, and then modifies the CWmin value based on these parameters. The AP then uses a beacon signal to inform the stations accessing the network of the new CWmin value. To verify the performance of our scheme, QualNet network simulations were performed, the results of which show us that, in terms of throughput, our proposed method outperforms conventional CSMA/CA schemes in wireless LAN environments with high station densities.

DOI： 10.1109/PACRIM.2015.7334856

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84958757333&origin=inward

Performance evaluation of multi-hop communication with a dynamic channel switching scheme in ROD-SAN 査読有り

Hidaka T., Nobayashi D., Fukuda Y., Tsukamoto K., Ikenaga T.

IEEE Pacific RIM Conference on Communications, Computers, and Signal Processing - Proceedings 2015-November 332 - 337 2015年11月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2015 IEEE. Wireless sensor and actuator networks (WSANs) are expected to be come fundamental technologies supporting machine-to-machine (M2M) communication and the internet of things (IoT). However, wireless sensors face inherent limitations because they must provide high demand response (DR) despite severely limited battery power. In an effort to achieve both power-saving characteristics in addition to high DR, we are working on research and development of radio-on-demand sensor and actuator networks (ROD-SANs), in which each node is equipped with a wake-up receiver that allows all nodes to stay in sleep mode most of the time, and transmit only after a wake-up signal is received. Since the wake-up signal can also include channel information, the sender nodes can direct the receiver nodes to switch communication channels when needed. However, as the number of nodes using the same channel increases, packet collisions occur more frequently, thereby degrading response performance. On the other hand, frequent channel switching inevitably increases channel switching delays. To simultaneously reduce both packet collisions and channel switching delays, we have extended the average-channel-utilization-based channel switching (ACS) scheme, discussed in our previous work on single-hop communication in a way that allows it to provide efficient performance in multi-hop communication. In this paper, based on simulations, we show how our scheme can improve the delivery ratio performance by approximately 20%.

DOI： 10.1109/PACRIM.2015.7334857

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84958757392&origin=inward

On Demand Routing Scheme for Real-Spatial Information based Group Communication 査読有り

Masaya Mitsuishi, Daiki Nobayashi, Takeshi Ikenaga, Yuji Oie, Hiroshi Ishinishi, Akira Nagata, Katsuichi Nakamura

Proc. on IEEE Pacific Rim Conference on Communications, Computers and Signal Processing (PACRIM) 2015 2015年08月

Transmission Channel Switching Based on Channel Utilization in ROD-SAN 査読有り

Takeo Hidaka, Daiki Nobayashi, Yutaka Fukuda, Kazuya Tsukamoto, Takeshi Ikenaga

Future Network System and Security, Springer International Publishing 129 - 138 2015年06月

A Self-adaptive Reliable Packet Transmission Scheme for Wireless Mesh Networks (共著) 査読有り

Shi Wenze, Takeshi Ikenaga, Daiki Nobayashi, Xinchun Yin, and Hui Xu

Proc. of The 5th International Workshop on Wireless Networks and Multimedia (WNM-2014) 2014年08月

Reliable Transmission with Multipath and Redundancy for Wireless Mesh Networks (共著) 査読有り

Shi Wenze, Takeshi Ikenaga, Daiki Nobayashi, Xinchun Yin, and Hui Xu

Proc. of The 5th International Workshop on Wireless Networks and Multimedia (WNM-2014) 2014年08月

Expiration Timer Control Method for QoS-aware Packet Chunking (共著) 査読有り

Hiroki Yanaga, Daiki Nobayashi, Takeshi Ikenaga

Proc. of The 38th Annual International Computers, Software & Applications Conference 638 - 639 2014年07月

Station Reassociation Scheme for Wireless Green Networking (共著) 査読有り

Kazumi Kumazoe, Daiki Nobayashi, Yutaka Fukuda, Takeshi Ikenaga

Proc. of International Workshop on Wireless Networks and Energy Saving Techniques (WNTEST) 2014年06月

Flow-based Routing Schemes for Minimizing Network Energy Consumption using OpenFlow (共著) 査読有り

Syouta Oda, Daiki Nobayashi, Yutaka Fukuda, Takeshi Ikenaga

Proc. of the 4th International COnference on Smart Grids, Green Communications and IT Energy-aware Technologies 2014年04月

Station Aggregation Scheme considering Channel Interface for Radio on Demand Networks (共著) 査読有り

Kazumi Kumazoe, Daiki Nobayashi, Yutaka Fukuda, Takeshi Ikenaga

Proc. of IEEE Pacific Rim Conference on Communications, Computers and Signal Processing 2013年08月

Performance Characterization of Streaming Video over TCP Variants (共著) 査読有り

Gaku Watanabe, Kazumi Kumazoe, Dirceu Cavendish, Daiki Nobayashi, Takeshi Ikenaga, Yuji Oie

Proc. of The Fifth International Conference on Evolving Internet (INTERNET 2013) 2013年07月

Multiple Station Aggregation Procedure for Radio-On-Demand WLANs （共著）査読有り

Kazumi Kumazoe, Daiki Nobayashi, Yutaka Fukuda, Takeshi Ikenaga, Kenichi Abe

Proc. of 2012 Seventh International Conference on Broadband, Wireless Computing, Communication and Applications (BWCCA 2012) 156 - 161 2012年11月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

カナダビクトリア 2012年11月12日 - 2012年11月14日

With the rapid growth in Internet network infrastructure, there is an urgent need to deploy energy-efficient networking technology. In particular, there is a need for energy-efficient wireless local area networks (WLANs), which are widely used due to their ease of deployment and low installation costs. To realize this, radio-on-demand (ROD) have been proposed. Access points (APs) in ROD are equipped with wake-up receivers that change their status to sleep or active mode based on the network traffic distribution. This study proposes a station aggregation scheme targeting multiple stations (STAs) in ROD. In this scheme, APs cooperate with each other and aggregate their STAs based on their utilization. Simulation results demonstrate the effectiveness of the scheme in terms of power saving and load balancing in ROD networks.

DOI： 10.1109/BWCCA.2012.53

Autonomous Dynamic Transmission Scheduling Based on Neighbor Node Behavior for Multihop Wireless Networks（共著）査読有り

Daiki Nobayashi, Yutaka Fukuda, Takeshi Ikenaga

Proc. of the 37th IEEE Conference on Local Computer Network (LCN) 2012 268 - 271 2012年10月

担当区分：責任著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

アメリカ合衆国フロリダ州 2012年10月22日 - 2012年10月25日

Multihop wireless networks (MWNs) can dynamically extend the coverage area of wireless local area networks (LANs).Communication performance of MWNs that use a single channel decreases due to interference between nodes occurring when frames are being relayed.In this paper, we proposed an autonomous dynamic transmission scheduling scheme for MWNs that is based on the behavior of neighbor nodes. In our proposed scheme, each node has a transmission priority obtained by monitoring neighboring nodes. Because it is difficult for low priority node to obtain the right to transmit a frame, the proposed scheme can mitigate interferences among nodes. In this paper, we evaluate the proposed scheme by performing simulations, and show that it can improve performance in MWN communications.

DOI： 10.1109/LCN.2012.6423625

A network reconfiguration scheme against misbehaving nodes 査読有り

Nobayashi D., Sera T., Ikenaga T., Nakamura Y., Hori Y.

Proceedings - Conference on Local Computer Networks, LCN 424 - 431 2010年12月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Multi-hop wireless networks (MWNs) are rapidly gaining attention, because they can provide a wide coverage area to Internet users. To provide stable and high-performance network environments, security issues must be addressed. This paper focuses on the security issues in terms of anomalous relay nodes inside networks because their malicious behaviors can degrade the performance of MWNs. To maintain the network performance of MWNs, we propose a novel network reconfiguration scheme that each node reconstructs a network autonomously using the I/F of the neighbor nodes linked to a misbehaving node. Our proposed scheme reconfigurates topology with an emphasis on the reuse of I/F, the number of the links required to construct, transmission rates, performance anomaly, and network connectivity. We evaluate the effectiveness of the proposed schemes by simulations. The results of simulation indicate that the proposed scheme can prevent the communication performance degradation of the entire MWN. © 2010 IEEE.

DOI： 10.1109/LCN.2010.5735755

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=79955025771&origin=inward

Development of Single Sign-On system with hardware token and key management server 査読有り

Nobayashi D., Nakamura Y., Ikenaga T., Hori Y.

IEICE Transactions on Information and Systems ( 一般社団法人電子情報通信学会 ) E92-D ( 5 ) 826 - 835 2009年01月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

With the growth of the Internet, various types of services are rapidly expanding; such services include the World Wide Web (WWW), the File Transfer Protocol (FTP), and remote login. Consequently, managing authentication information, e.g., user ID/password pairs, keys, and certificates-is difficult for users, since the amount of required authentication information has been increased. To address this problem, researchers have developed a Single Sign-On (SSO) system that makes all the services available for a user via a one-time authentication: however, existing authentication systems cannot provide such SSO services for all kind of services on the Internet, even if the service provider deploys the SSO server. Further, existing systems also cannot provide the SSO service which does not make it conscious of a network domain to a user on secure network environment. Therefore, in this paper, we propose a new SSO system with a hardware token and a key management server to improve the safety, ubiquity, and adaptability of services. Further, we implement the proposed system and show its effectiveness through evaluation. Adding any functions for this system provides various conveniences to us. We also explore the ability to add functions to this system; for example, we add high trust connection functionality for a Web server and show its effectiveness. Copyright © 2009 The Institute of Electronics, Information and Communication Engineers.

DOI： 10.1587/transinf.E92.D.826

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=77950318880&origin=inward

Development of single sign-on system with hardware token and key management server 査読有り

Nobayashi D., Nakamura Y., Ikenaga T., Hori Y.

Second International Conference on Systems and Networks Communications, ICSNC 2007 2007年12月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

With the growth of the Internet, various types of services, such as World Wide Web (WWW), File Transfer Protocol (FTP), remote login, etc., are widely expanded. Consequently, it is difficult for users to manage all the authentication information, e.g., user ID/Password pairs, keys, and certificates, since the authentication information has been increased to use those services. Therefore, Single Sign-On (SSO) system, which makes all the services available for a user by only one-time authentication, has been developed. However, existing systems cannot provide all the SSO services for any kinds of services on the Internet even if the service provider deploys the SSO server. Therefore, in this paper, we propose a new SSO system with hardware token and key management server to improve the safety and the convenience. Furthermore, we implement the proposed system, and show its effectiveness through evaluation. In addition, adding any functions for this system provide various conveniences to us. As one example, we add high trust connection function for a Web server, and show its the effectiveness through evaluation by implementing it. © 2007 IEEE.

DOI： 10.1109/ICSNC.2007.31

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=47849120040&origin=inward

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