Sasase, Iwao

写真a

Affiliation

Faculty of Science and Technology, Department of Information and Computer Science (Yagami)

Position

Professor

E-mail Address

E-mail address

External Links

Profile 【 Display / hide

  • Iwao Sasase was born in Osaka, Japan in 1956. He received the B.E., M.E., and D. Eng. degrees in Electrical Engineering from Keio University, Yokohama, Japan, in 1979, 1981 and 1984, respectively. From 1984 to 1986, he was a Post Doctoral Fellow and Lecturer of Electrical Engineering at University of Ottawa, ON, Canada. He is currently a Professor of Information and Computer Science at Keio University, Yokohama, Japan. His research interests include modulation and coding, broadband mobile and wireless communications, optical communications, communication networks, information theory and network security. He has authored more than 285 journal papers and 437 international conference papers. He granted 44 Ph.D. degrees to his students in the above field. Dr. Sasase received the 1984 IEEE Communications Society (ComSoc) Student Paper Award (Region 10), 1986 Inoue Memorial Young Engineer Award, 1988 Hiroshi Ando Memorial Young Engineer Award, 1988 Shinohara Memorial Young Engineer Award, 1996 Institute of Electronics, Information, and Communication Engineers (IEICE) of Japan Switching System Technical Group Best Paper Award, WPMC2008 Best Paper Award、2015 The Telecommunication Advanvecement Foundation Telecom Technical Award, and 2018 IEICE Communications Society Maganine AWard. He is now serving as IEEE Tokyo Section Chair. He was Board of Governors Member-at-Large (2010-2012), Japan Chapter Chair (2011-2012), Director of the Asia Pacific Region (2004-2005), Chair of the Satellite and Space Communications Technical Committee (2000-2002) of IEEE ComSoc., President (2013-2014), Vice President of IEICE (2014-2015), President in Elect (2012-2013) and Vice President of the IEICE Communications Society (2004-2006), Chair of the Network System Technical Committee (2004-2006), Chair of the Communication System Technical Committee (2002-2004) of IEICE Communications Society, Director of the Society of Information Theory and Its Applications in Japan (2001-2002). He is Fellow of IEICE, Senior Member of IEEE, Member of Information Processing Society of Japan, respectively.

Profile Summary 【 Display / hide

  • His research interests include modulation and coding, broadband mobile and wireless communications, optical communications, communication networks, information theory, network security, IoT, and adghon and Sendor networks. He has authored more than 285 journal papers and 437 international conference papers. He granted 44 Ph.D. degrees to his students in the above field. In the Keio University COE program on Optical and Electronic Device Technology for Access Network, he is engaged in the following research topics; (1) High-speed transmission and QoS control in the broadband mobile communications by utilizing adaptive modulation, space and time coding, multiple access, and interference suppression, (2) QoS control and resource management in wireless home link and ad-hoc networks, (3) Flexible networking at the edge node of the photonic network to satisfy multicast and QoS requests by utilizing optical CDMA, WDMA, and optical burst switching. His main research interests include broadband mobile communications, wireless home link, and photonic networks. His main research contribution include the pioneer research on wireless home link scheme known as “wireless 1394”, and the broadband mobile communication joint research with NTT DoCoMo for 4G mobile communications. He has published more than 275 refereed journal papers and presented more than 405 international conference papers. He is the co-author of the books “Advanced Modulation Technology (in Japanese) Triceps, 1995 and “Optical Synchronous CDMA (Encyclopedia of Telecommunications and Signal Processing)”, Wiley.

Career 【 Display / hide

  • 1984.04
    -
    1985.04

    カナダ オタワ大学(工学部電気工学科) ,ポストドクトラルフェロー

  • 1985.05
    -
    1986.03

    カナダ オタワ大学(工学部電気工学科) ,講師

  • 1986.04
    -
    1988.03

    慶應義塾大学(理工学部電気工学科) ,助手

  • 1986.04
    -
    1989.03

    理工学部2年 ,クラス担任

  • 1988.04
    -
    1989.03

    電気工学科カリキュラム検討委員会 ,委員

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Academic Background 【 Display / hide

  • 1979.03

    Keio University, Faculty of Engineering, 電気工学科

    University, Graduated

  • 1981.03

    Keio University, Graduate School, Division of Engineering, 電気工学専攻

    Graduate School, Completed, Master's course

  • 1984.03

    Keio University, Graduate School, Division of Engineering, 電気工学専攻

    Graduate School, Completed, Doctoral course

Academic Degrees 【 Display / hide

  • 工学 , Keio University, 1984.03

 

Research Areas 【 Display / hide

  • Communication/Network engineering (Information and Communication Engineering)

Research Keywords 【 Display / hide

  • IoT

  • アドホック・センサーネットワーク

  • Wireless Communication

  • Oprical Communications

  • 情報セキュリティ

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Research Themes 【 Display / hide

  • Broadband Mobile Communocation joint Research Project, 

    2003
    -
    2007

     View Summary

    The broadband mobile communication joint research with NTT DoCoMo for 4G mobile communications

 

Books 【 Display / hide

  • 情報伝送の理論と方式

    SASASE IWAO, 2006.06

    Scope: 333

  • Encyclopedia of Telecommunications and Signal Processing

    Tomoaki Ohtsuki and Iwao Sasase, Wiley, 2002

  • 改訂 電子情報通信用語辞典

    SASASE IWAO, 1999.06

    Scope: 1280

  • 「マルチメディア産業応用技術体系」

    片方善治監修, (笹瀬巌 第2編第8節 「ディジタル変復調技術」(276-289p.)を分担執筆), 1206p, フジテクノシステム, 1997.08

  • 「次世代ディジタル変復調技術」

    笹瀬巌監修,笹瀬巌 1-6章(1-116p.), 占部健三 7章, 都竹愛一郎 8章, 前田和貴 9章, 矢田博昭 10章を分担執筆) 239p, トリケップス, 1995.05

Papers 【 Display / hide

  • Traffic Feature-Based Botnet Detection Scheme Emphasizing the Importance of Long Patterns

    An Y., Haruta S., Choi S., Sasase I.

    Advances in Intelligent Systems and Computing (Advances in Intelligent Systems and Computing)  1062   181 - 188 2020

    ISSN  9783030312534

     View Summary

    © 2020, Springer Nature Switzerland AG. The botnet detection is imperative. Among several detection schemes, the promising one uses the communication sequences. The main idea of that scheme is that the communication sequences represent special feature since they are controlled by programs. That sequence is tokenized to truncated sequences by n-gram and the numbers of each pattern’s occurrence are used as a feature vector. However, although the features are normalized by the total number of all patterns’ occurrences, the number of occurrences in larger n are less than those of smaller n. That is, regardless of the value of n, the previous scheme normalizes it by the total number of all patterns’ occurrences. As a result, normalized long patterns’ features become very small value and are hidden by others. In order to overcome this shortcoming, in this paper, we propose a traffic feature-based botnet detection scheme emphasizing the importance of long patterns. We realize the emphasizing by two ideas. The first idea is normalizing occurrences by the total number of occurrences in each n instead of the total number of all patterns’ occurrences. By doing this, smaller occurrences in larger n are normalized by smaller values and the feature becomes more balanced with larger value. The second idea is giving weights to the normalized features by calculating ranks of the normalized feature. By weighting features according to the ranks, we can get more outstanding features of longer patterns. By the computer simulation with real dataset, we show the effectiveness of our scheme.

  • Low-complexity joint antenna and user selection scheme for the downlink multiuser massive MIMO system with complexity reduction factors

    Aye Mon Htun, Maung Sann Maw and Iwao Sasase

    IEICE Trans. on Communications (IEICE)  E102B ( 3 ) 592 - 602 2019.03

    Research paper (scientific journal), Joint Work, Accepted,  ISSN  09168516

     View Summary

    Copyright © 2019 The Institute of Electronics, Information and Communication Engineers. Multiuser massive multi-input multi-output (MU massive MIMO) is considered as a promising technology for the fifth generation (5G) of the wireless communication system. In this paper, we propose a low-complexity joint antenna and user selection scheme with block diagonalization (BD) precoding for MU massive MIMO downlink channel in the time division duplex (TDD) system. The base station (BS) is equipped with a large-scale transmit antenna array while each user is using the single receive antenna in the system. To reduce the hardware cost, BS will be implemented by limited number of radio frequency (RF) chains and BS must activate some selected transmit antennas in the BS side for data transmitting and some users’ receive antennas in user side for data receiving. To achieve the reduction in the computation complexity in the antenna and user selection while maintaining the same or higher sum-rate in the system, the proposed scheme relies on three complexity reduction key factors. The first key factor is that finding the average channel gains for the transmit antenna in the BS side and the receive antenna in the user side to select the best channel gain antennas and users. The second key factor called the complexity control factor ξ(Xi) for the antenna set and the user set limitation is used to control the complexity of the brute force search. The third one is that using the assumption of the point-to-point deterministic MIMO channel model to avoid the singular value decomposition (SVD) computation in the brute force search. We show that the proposed scheme offers enormous reduction in the computation complexity while ensuring the acceptable performance in terms of total system sum-rate compared with optimal and other conventional schemes.

  • An effective feature selection scheme for android ICC-based malware detection using the gap of the appearance ratio

    Osuge K., Kato H., Haruta S., Sasase I.

    IEICE Transactions on Information and Systems (IEICE Transactions on Information and Systems)  E102D ( 6 ) 1136 - 1144 2019

    ISSN  09168532

     View Summary

    Copyright © 2019 The Institute of Electronics, Information and Communication Engineers. Android malwares are rapidly becoming a potential threat to users. Among several Android malware detection schemes, the scheme using Inter-Component Communication (ICC) is gathering attention. That scheme extracts numerous ICC-related features to detect malwares by machine learning. In order to mitigate the degradation of detection performance caused by redundant features, Correlation-based Feature Selection (CFS) is applied to feature before machine learning. CFS selects useful features for detection in accordance with the theory that a good feature subset has little correlation with mutual features. However, CFS may remove useful ICC-related features because of strong correlation between them. In this paper, we propose an effective feature selection scheme for Android ICC-based malware detection using the gap of the appearance ratio. We argue that the features frequently appearing in either benign apps or malwares are useful for malware detection, even if they are strongly correlated with each other. To select useful features based on our argument, we introduce the proportion of the appearance ratio of a feature between benign apps and malwares. Since the proportion can represent whether a feature frequently appears in either benign apps or malwares, this metric is useful for feature selection based on our argument. Unfortunately, the proportion is ineffective when a feature appears only once in all apps. Thus, we also introduce the difference of the appearance ratio of a feature between benign apps and malwares. Since the difference simply represents the gap of the appearance ratio, we can select useful features by using this metric when such a situation occurs. By computer simulation with real dataset, we demonstrate our scheme improves detection accuracy by selecting the useful features discarded in the previous scheme.

  • An Energy Efficient Target Specific Code Dissemination Scheme with Forwarder Selection Algorithm in WSNs

    Asahina H., Toyoda K., Sasase I., Mathiopoulos P., Yamamoto H.

    IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC (IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC)  2018-September 2018.12

    ISSN  9781538660096

     View Summary

    © 2018 IEEE. In order to fix a bug or install a new application, disseminating a code to specific target sensors is an important management task in wireless sensor networks. In order to disseminate a code to specific target sensors in an energy efficient manner, it is required to select the minimum required number of forwarders with a small number of control messages. In this paper, we propose an energy efficient target specific code dissemination scheme with a forwarder selection algorithm. The proposed scheme consists of two steps, (i) a forwarder selection algorithm with a control message suppression, (ii) unnecessary forwarders reduction with a sleep mechanism. In order to select the minimum required forwarders with a small number of control messages, we propose an algorithm to select a forwarder where more target sensors are reachable, through a single control message by leveraging overhearing of control messages. In addition, in order to reduce the number of forwarders, we propose a sleep mechanism to put unnecessary forwarders to sleep where any target sensor is not reachable. A performance analysis has shown that the number of control messages of the proposed scheme is always theoretically smaller than that of a previously published forwarder selection scheme under the same condition. In addition, we have shown that the proposed scheme reduces the energy consumption compared with the previous scheme.

  • Encounter Record Reduction Scheme based on Theoretical Contact Probability for Flooding Attack Mitigation in DTN

    Keisuke Arai, Shuichiro Haruta, Hiromu Asahina and Iwao Sasase

    The 2018 24th Asia-Pacific Conference on Communications (APCC2018) (2018 24th Asia-Pacific Conference on Communications, APCC 2018)     34 - 39 2018.11

    Research paper (international conference proceedings), Joint Work, Accepted,  ISSN  9781538669280

     View Summary

    © 2018 IEEE. Delay Tolerant Network (DTN) is characterized by a lack of end-to-end connectivity. Due to this, detecting flooding attack in DTN is a challenging and important task. Among several schemes against flooding attack in DTN, the scheme using Encounter Record (ER) that consists of past transmission history of each node is gathering attention. Since ER entries are exchanged between nodes, a node can detect an attacker whose transmission rate is too much. Although an attacker may falsify entry to pretend that his/her transmission rate is less than the actual value, it can also be detected through the contradiction between a falsified entry and another entry. However, since a node sends all ER entries in its own buffer regardless of whether an entry is helpful to detect an attacker or not, the energy consumption increases as the number of entries increases. In this paper, we propose an ER reduction scheme based on theoretical contact probability for flooding attack mitigation. We focus on the fact that if the falsified entry does not exist, corresponding entries are not helpful to detect an attacker. Since the falsified entries are propagated over the network with the lapse of time, the probability that there is no contradicting entries over the network gets higher if a node has not received any contradicting entries for a sufficient time. By removing such entries, the energy consumption can be reduced while the effectiveness of ER is kept. By computer simulation, we demonstrate our scheme successfully reduce the energy consumption while the same level of performance is achieved.

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Papers, etc., Registered in KOARA 【 Display / hide

Presentations 【 Display / hide

  • False Density Information Attack Detection Scheme Using Overlap of Communication Range in VANE

    Masashi Yoshida, Hiromu Asahina, Shuichiro Haruta and underline{Iwao Sasase

    電子情報通信学会通信方式研究会, 2018.11, Oral Presentation(general)

  • Feature Selection Scheme for Android ICC-related Features Based on the Gap of the Appearance Ratio

    Kyohei Osuge, Hiroya Kato, Shuichiro Haruta and Iwao Sasase

    電子情報通信学会通信方式研究会, 2018.11, Oral Presentation(general)

  • Wi-Fiフレデータを用いた大学図書館における滞在時間の推定手法

    SASASE IWAO

    電子情報通信学会通信方式研究会, 2018.11, Oral Presentation(general)

  • 図書・雑誌検索実験から得られた大学図書館ユーザ行動調査

    SASASE IWAO

    電子情報通信学会通信方式研究会, 2018.11, Oral Presentation(general)

  • Encounter Record Reduction Scheme based on Theoretical Contact Probability for Flooding Attack Mitigation in DTN

    Keisuke Arai, Shuichiro Haruta, Hiromu Asahina and Iwao Sasase

    電子情報通信学会通信方式研究会 (沖縄) , 2018.07, Oral Presentation(general), 電子情報通信学会通信方式研究会

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Research Projects of Competitive Funds, etc. 【 Display / hide

  • IoTにおける安全なWebインタフェースおよび高効率なデータ配信方式に関する研究

    2017.04
    -
    2020.03

    MEXT,JSPS, Grant-in-Aid for Scientific Research, 笹瀬 巌, Grant-in-Aid for Scientific Research (C), Principal Investigator

  • Research of Secure Access Control Schemes for Realization of IoT with High Reliability

    2014.04
    -
    2017.03

    MEXT,JSPS, Grant-in-Aid for Scientific Research, 笹瀬 巌, Grant-in-Aid for Scientific Research (C), Principal Investigator

     View Summary

    IoT (Internet of Things), which builds a network between the devices automatically, is the important technology which achieves the realization of useful applications such as a monitoring of a structure, an accident detection, the automatic meter reading and inventory control, and thus, power-saving, real time, high reliability and security are required. However the consideration about power-saving, high reliability and security is not enough.
    In this research, we considered the routing, media access control and aggressive defense with power-saving, high reliability and high security when assuming the next generation application in the above-mentioned IoT.

Awards 【 Display / hide

  • 義塾賞

    2018.11, 慶應義塾, 情報通信ネットワーク分野における先駆者的研究・教育および人材育成への貢献

    Type of Award: Keio commendation etc.

  • 第一回電子錠通信学会通信ソサイエティマガジン賞

    笹瀬 巌, 2018.05, 田氏情報通信学会通信ソサイエティ, 受賞論文;「難関国際会議への論文投稿を通じた若手の育成 ―持続可能な研究コミュニティの確立― 」40号 Vol. 10 No.4 , 2017年3月掲載

    Country: 日本

  • 第30回電気通信普及財団賞(テレコムシステム技術賞賞奨励賞)

    豊田健太郎、笹瀬巌, 2015.03, 電気通信普及財団, 受賞論文:「Unsupervised Clustering-based SPITters Detection Scheme (論文掲載:Journal of Information Processing, Vol. 23, No.1, 2015年1月

     View Description

    受賞理由:IP電話の普及に伴い、広告や詐欺を目的とした迷惑電話の増加が問題となってい る。電話が着信したとき、受信者は応答するまで通話内容を把握でき ないた め、リアルタイムに迷惑電話かどうか判別することは困難である。本論文は、プ ラーバシーの点で問題のない迷惑電話判別法として、通話の特徴 量を元に2つの クラスに分類することで、通話内容を知ることなく判別できる手法を提案し、そ の有効性を定量的に示しており、従来判別が困難であっ た、詐欺を目的とする 低発信頻度の迷惑電話発信者の判別にも有効であることを明らかにしており、安 心・安全な通信に貢献する論文であり、テレコム システム技術賞奨励賞にふさ わしい論文と評価される。

  • 第30回電気通信普及財団賞(テレコムシステム技術賞賞奨励賞)

    豊田健太郎, 笹瀬巌, 2014.03, 電気通信普及財団, 受賞論文:「Unsupervised Clustering-based SPITters Detection Scheme (論文掲載:Journal of Information Processing, Vol. 23, No.1, 2015年1月

    Country: 日本

     View Description

    受賞理由:IP電話の普及に伴い、広告や詐欺を目的とした迷惑電話の増加が問題となってい る。電話が着信したとき、受信者は応答するまで通話内容を把握でき ないた め、リアルタイムに迷惑電話かどうか判別することは困難である。本論文は、プ ラーバシーの点で問題のない迷惑電話判別法として、通話の特徴 量を元に2つの クラスに分類することで、通話内容を知ることなく判別できる手法を提案し、そ の有効性を定量的に示しており、従来判別が困難であっ た、詐欺を目的とする 低発信頻度の迷惑電話発信者の判別にも有効であることを明らかにしており、安 心・安全な通信に貢献する論文であり、テレコム システム技術賞奨励賞にふさ わしい論文と評価される。

  • 電子情報通信学会フェロー

    2009.09, 電子情報通信学会

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Courses Taught 【 Display / hide

  • SPECIAL EXERCISES ON INFORMATION AND COMPUTER SCIENCE

    2020

  • RECITATION IN INFORMATION AND COMPUTER SCIENCE

    2020

  • LABORATORIES IN INFORMATION AND COMPUTER SCIENCE 1B

    2020

  • LABORATORIES IN INFORMATION AND COMPUTER SCIENCE 1A

    2020

  • INFORMATION THEORY

    2020

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Social Activities 【 Display / hide

  • JEITA教育実施検討WG

    2010.07
    -
    Present
  • 日本放送協会

    2010.04
    -
    2016.03
  • 経済産業省地域技術開発支援事業

    2010.04
    -
    2010.09
  • 科学技術振興機構

    2009.04
    -
    2012.03
  • 総務省

    2009.01
    -
    Present

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Memberships in Academic Societies 【 Display / hide

  • 電子情報通信学会知的情報とセンサネットワーク研究会, 

    2013.05
    -
    Present
  • 電子情報通信学会第25回情報伝送と信号処理ワークショップ, 

    2012.04
    -
    2012.11
  • The 10th International Conference on Optical Internet (COIN2012), 

    2012.01
    -
    2012.05
  • The Forth International Conference on Communications and Electronics (ICCE2012), 

    2012.01
    -
    2012.08
  • 電子情報通信学会第24回情報伝送と信号処理ワークショップ, 

    2011.04
    -
    2011.11

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Committee Experiences 【 Display / hide

  • 2018.04
    -
    Present

    実行委員, 電子情報通信学会第31回情報伝送と信号処理ワークショップ

  • 2018.04
    -
    Present

    主査, 電気通信協会ブロードバンドユビキタス調査会

  • 2017.04
    -
    2018.03

    実行委員, 電子情報通信学会第30回情報伝送と信号処理ワークショップ

  • 2017.01
    -
    Present

    Chair, IEEE Tokyo Section

  • 2016.10
    -
    Present

    戦略的情報通信研究開発推進事業(SCOPE)に係る課題の専門評価委員, 総務省

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