Path-Selection Method Based on the Available Bandwidth of Interfaces

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.5th Annual Conference on Computational Science & Computational Intelligence (CSCI\u2718), December 13-15, 2018, Las Vegas, Nevada, US

Autonomous Data Transmission Control Based on Node Density for Multiple Spatio-temporal Data Retention

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.7th IEEE International Conference on Cloud Networking (CloudNet 2018), 22-24 October, 2018, Tokyo, Japa

Adaptive Server and Path Switching for Content Delivery Networks

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

Experimental Performance Evaluation of the Collisions in LoRa Communications

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.5th Annual Conference on Computational Science & Computational Intelligence (CSCI\u2718), December 13-15, 2018, Las Vegas, Nevada, US

Clustering Malicious DNS Queries for Blacklist-Based Detection

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

Development of Data Collection Platform for Running Cars by using 920MHz LoRa Communication in Urban Area

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 today’s IoT (Internet of Things) and the MaaS infrastructures, however, data ownership is owned by the vendor created onboard sensor, such as car-navigation systems and driving recorders, and not everyone can easily leverage the data. Therefore, it is necessary to collect various information from sensors mounted on a vehicle at a low cost and effective. This paper proposes the data collection platform using the LoRa andWi-Fi from running cars. Through the demonstration experiment in the urban area, we clarified the acquisition performance of GPS data of cars by LoRa communication and the importance of data collection using Wi-Fi.2020 International Conference on Emerging Technologies for Communications (ICETC2020), December 2-4, 2020, Online, Virtual Conferenc

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

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.COMPSAC 2018: The 42nd IEEE International Conference on Computers, Software & Applications, July 23-27, 2018, Tokyo, Japa

Managing Path Switching in Multipath Video Streaming

Video streaming has become the major source of Internet traffic nowadays. Considering that content delivery network providers utilize Video over Hypertext Transfer Protocol/Transmission Control Protocol (HTTP/TCP) as the preferred protocol stack for video streaming, understanding TCP performance in transporting video streams has become paramount. Recently, multipath transport protocols have allowed video streaming over multiple paths to become a reality. In this paper, we analyze the impact of path switching on multipath video streaming and network performance, and propose new schedulers which minimize the number of path switching. We utilize network performance measures, as well as video quality metrics, to characterize the performance and interaction between network and application layers of video streams for various network scenarios.The Eleventh International Conference on Evolving Internet (INTERNET 2019), June 30 to July 04, 2019, Rome, Ital

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

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.2020 International Conference on Computational Science and Computational Intelligence (CSCI 2020), 16-18 December, 2020, Las Vegas, Nevada, US

Experimental Investigation of Static Channel Bonding Performance in Competitive Environment －Impact of Different MAC Procedures in 802.11ac－

Channel bonding technology, which bundles multiple adjacent channels for frame transmission, is one of the promising way for improving throughput performance in IEEE802.11ac wireless LANs. However, channel bonding technology leads to co-channel interference with other access points (APs) within the bonded channels. In our previous study, we investigated transmission performance of several commercially-available 802.11ac APs. As a result, we clarified three communication procedures from difference in method of implementation of Request To Send (RTS) / Clear To Send (CTS) or not. Furthermore, we investigated the impact of RTS/CTS on transmission performance by conducting experiments where two APs using RTS/CTS are competing in a bonded channels. However, we have not investigated transmission performance in the case that APs with different transmission procedures compete with each other in a bonded channels. Therefore, in this study, we conducted experiments using real WLAN products. Then, we compared and evaluated the communication performance in the case that two APs with different transmission procedures compete in the same channel. As a result, we showed that the AP employing CTS-to-self doesn’t set duration time in CTS frames, thereby the communication performance of the AP using RTS/CTS in channel bonding degrades due to frequent collisions in conflict channel. On the other hand, since AP not using RTS/CTS dynamically adjusts the number of data frames for each transmission opportunity to avoid frame collisions, we confirmed that the communication performance can be relatively maintained even under the competitive environment. / IEEE802.11ac規格の通信高速化技術の一つに、隣接する複数のチャネルをまとめて利用するチャネルボンディング機能がある。しかし、通信帯域が拡大するため他の無線LAN機器と競合しやすくなってしまう。先行研究では、競合しない環境の単一のAPの通信性能を調査し、オプション機能のRequest To Send (RTS) / Clear To Send (CTS)の実装方法の違いから3パターンの通信手順があることを明らかにしたうえで、RTS/CTS利用の有無が競合時に性能に与える影響を調査した。しかし、CTS-to-Selfによる競合時の影響は未だ明らかになっていない。そこで本研究では、実機を用いた実験を行い、CTS-to-Selfによる競合時の通信性能を調査するとともに、3パターンの通信手順の競合時における各通信性能の比較および評価を行った。その結果、CTS-to-selfによる通信手順ではNAV期間が確保できていないためフレーム衝突が起こりやすく、RTS/CTSを利用しチャネルボンディングさせていたAPに悪影響を与えていた。それに対して、RTS/CTSを利用しないAPは、送信機会毎のデータフレーム数を調節しながら通信していたためフレーム衝突が起こりにくく、お互いの通信性能への影響が低減されていることがわかった。電子情報通信学会 スマート無線研究会（SR）, 2018年10月30日-31日, Bangkok, Thailan