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[Keyword] AF(873hit)

101-120hit(873hit)

  • Privacy-Enhancing Trust Infrastructure for Process Mining

    Sven WOHLGEMUTH  Kazuo TAKARAGI  

     
    PAPER

      Vol:
    E101-A No:1
      Page(s):
    149-156

    Threats to a society and its social infrastructure are inevitable and endanger human life and welfare. Resilience is a core concept to cope with such threats in strengthening risk management. A resilient system adapts to an incident in a timely manner before it would result in a failure. This paper discusses the secondary use of personal data as a key element in such conditions and the relevant process mining in order to reduce IT risk on safety. It realizes completeness for such a proof on data breach in an acceptable manner to mitigate the usability problem of soundness for resilience. Acceptable soundness is still required and realized in our scheme for a fundamental privacy-enhancing trust infrastructure. Our proposal achieves an IT baseline protection and properly treats personal data on security as Ground Truth for deriving acceptable statements on data breach. An important role plays reliable broadcast by means of the block chain. This approaches a personal IT risk management with privacy-enhancing cryptographic mechanisms and Open Data without trust as belief in a single-point-of-failure. Instead it strengthens communities of trust.

  • Protocol-Aware Packet Scheduling Algorithm for Multi-Protocol Processing in Multi-Core MPL Architecture

    Runzi ZHANG  Jinlin WANG  Yiqiang SHENG  Xiao CHEN  Xiaozhou YE  

     
    PAPER-Architecture

      Pubricized:
    2017/07/14
      Vol:
    E100-D No:12
      Page(s):
    2837-2846

    Cache affinity has been proved to have great impact on the performance of packet processing applications on multi-core platforms. Flow-based packet scheduling can make the best of data cache affinity with flow associated data and context structures. However, little work on packet scheduling algorithms has been conducted when it comes to instruction cache (I-Cache) affinity in modified pipelining (MPL) architecture for multi-core systems. In this paper, we propose a protocol-aware packet scheduling (PAPS) algorithm aiming at maximizing I-Cache affinity at protocol dependent stages in MPL architecture for multi-protocol processing (MPP) scenario. The characteristics of applications in MPL are analyzed and a mapping model is introduced to illustrate the procedure of MPP. Besides, a stage processing time model for MPL is presented based on the analysis of multi-core cache hierarchy. PAPS is a kind of flow-based packet scheduling algorithm and it schedules flows in consideration of both application-level protocol of flows and load balancing. Experiments demonstrate that PAPS outperforms the Round Robin algorithm and the HRW-based (HRW) algorithm for MPP applications. In particular, PAPS can eliminate all I-Cache misses at protocol dependent stage and reduce the average CPU cycle consumption per packet by more than 10% in comparison with HRW.

  • A Safe and Comprehensive Route Finding Algorithm for Pedestrians Based on Lighting and Landmark Conditions

    Siya BAO  Tomoyuki NITTA  Masao YANAGISAWA  Nozomu TOGAWA  

     
    PAPER-Intelligent Transport System

      Vol:
    E100-A No:11
      Page(s):
    2439-2450

    In this paper, we propose a safe and comprehensive route finding algorithm for pedestrians based on lighting and landmark conditions. Safety and comprehensiveness can be predicted by the five possible indicators: (1) lighting conditions, (2) landmark visibility, (3) landmark effectiveness, (4) turning counts along a route, and (5) road widths. We first investigate impacts of these five indicators on pedestrians' perceptions on safety and comprehensiveness during route findings. After that, a route finding algorithm is proposed for pedestrians. In the algorithm, we design the score based on the indicators (1), (2), (3), and (5) above and also introduce a turning count reduction strategy for the indicator (4). Thus we find out a safe and comprehensive route through them. In particular, we design daytime score and nighttime score differently and find out an appropriate route depending on the time periods. Experimental simulation results demonstrate that the proposed algorithm obtains higher scores compared to several existing algorithms. We also demonstrate that the proposed algorithm is able to find out safe and comprehensive routes for pedestrians in real environments in accordance with questionnaire results.

  • Distortion Control and Optimization for Lossy Embedded Compression in Video Codec System

    Li GUO  Dajiang ZHOU  Shinji KIMURA  Satoshi GOTO  

     
    PAPER-Coding Theory

      Vol:
    E100-A No:11
      Page(s):
    2416-2424

    For mobile video codecs, the huge energy dissipation for external memory traffic is a critical challenge under the battery power constraint. Lossy embedded compression (EC), as a solution to this challenge, is considered in this paper. While previous studies in lossy EC mostly focused on algorithm optimization to reduce distortion, this work, to the best of our knowledge, is the first one that addresses the distortion control. Firstly, from both theoretical analysis and experiments for distortion optimization, a conclusion is drawn that, at the frame level, allocating memory traffic evenly is a reliable approximation to the optimal solution to minimize quality loss. Then, to reduce the complexity of decoding twice, the distortion between two sequences is estimated by a linear function of that calculated within one sequence. Finally, on the basis of even allocation, the distortion control is proposed to determine the amount of memory traffic according to a given distortion limitation. With the adaptive target setting and estimating function updating in each group of pictures (GOP), the scene change in video stream is supported without adding a detector or retraining process. From experimental results, the proposed distortion control is able to accurately fix the quality loss to the target. Compared to the baseline of negative feedback on non-referred B frames, it achieves about twice memory traffic reduction.

  • Forecasting Network Traffic at Large Time Scales by Using Dual-Related Method

    Liangrui TANG  Shiyu JI  Shimo DU  Yun REN  Runze WU  Xin WU  

     
    PAPER-Network

      Pubricized:
    2017/04/24
      Vol:
    E100-B No:11
      Page(s):
    2049-2059

    Network traffic forecasts, as it is well known, can be useful for network resource optimization. In order to minimize the forecast error by maximizing information utilization with low complexity, this paper concerns the difference of traffic trends at large time scales and fits a dual-related model to predict it. First, by analyzing traffic trends based on user behavior, we find both hour-to-hour and day-to-day patterns, which means that models based on either of the single trends are unable to offer precise predictions. Then, a prediction method with the consideration of both daily and hourly traffic patterns, called the dual-related forecasting method, is proposed. Finally, the correlation for traffic data is analyzed based on model parameters. Simulation results demonstrate the proposed model is more effective in reducing forecasting error than other models.

  • Timed Model-Based Formal Analysis of a Scheduler of Qplus-AIR, an ARINC-653 Compliance RTOS

    Sanghyun YOON  Dong-Ah LEE  Eunji PAK  Taeho KIM  Junbeom YOO  

     
    LETTER-Software System

      Pubricized:
    2017/06/23
      Vol:
    E100-D No:10
      Page(s):
    2644-2647

    Qplus-AIR is a real-time operating system for avionics, and its safety and correctness should be analyzed and guaranteed. We performed model checking a version of Qplus-AIR with the Times model checker and identified one abnormal case that might result in safety-critical situations.

  • Mitigating Use-After-Free Attacks Using Memory-Reuse-Prohibited Library

    Toshihiro YAMAUCHI  Yuta IKEGAMI  Yuya BAN  

     
    PAPER-Operating system and network Security

      Pubricized:
    2017/07/21
      Vol:
    E100-D No:10
      Page(s):
    2295-2306

    Recently, there has been an increase in use-after-free (UAF) vulnerabilities, which are exploited using a dangling pointer that refers to a freed memory. In particular, large-scale programs such as browsers often include many dangling pointers, and UAF vulnerabilities are frequently exploited by drive-by download attacks. Various methods to prevent UAF attacks have been proposed. However, only a few methods can effectively prevent UAF attacks during runtime with low overhead. In this paper, we propose HeapRevolver, which is a novel UAF attack-prevention method that delays and randomizes the timing of release of freed memory area by using a memory-reuse-prohibited library, which prohibits a freed memory area from being reused for a certain period. The first condition for reuse is that the total size of the freed memory area is beyond the designated size. The threshold for the conditions of reuse of the freed memory area can be randomized by HeapRevolver. Furthermore, we add a second condition for reuse in which the freed memory area is merged with an adjacent freed memory area before release. Furthermore, HeapRevolver can be applied without modifying the target programs. In this paper, we describe the design and implementation of HeapRevolver in Linux and Windows, and report its evaluation results. The results show that HeapRevolver can prevent attacks that exploit existing UAF vulnerabilities. In addition, the overhead is small.

  • The Invulnerability of Traffic Networks under New Attack Strategies

    Xin-Ling GUO  Zhe-Ming LU  Hui LI  

     
    PAPER-Graphs and Networks

      Vol:
    E100-A No:10
      Page(s):
    2106-2112

    In this paper, invulnerability and attack strategies are discussed for the undirected unweighted urban road networks and the directed weighted taxi networks of Beijing. Firstly, five new attack strategies, i.e., Initial All Degree (IAD), Initial All Strength (IAS), Recalculated Closeness (RC), Recalculated All Degree (RAD) and Recalculated All Strength (RAS) and five traditional attack strategies, i.e., Initial Degree (ID), Initial Betweenness (IB), Initial Closeness (IC), Recalculated Degree (RD) and Recalculated Betweenness (RB) are adopted to provoke the nodes failure. Secondly, we assess the impacts of these attack strategies using two invulnerability metrics, i.e., S (the relative size of the giant component) and E (the average network efficiency) through simulation experiments by MATLAB. Furthermore, we obtain some conclusions on the basis of the simulation results. Firstly, we discover that IB is more efficient than others for the undirected unweighted 5th ring Beijing road network based on S, and IB is more efficient than others at the beginning while ID is more efficient than IB at last based on E, while IAD causes a greater damage than IAS for the directed weighted 5th ring Beijing taxi network no matter with metrics S or E. Secondly, we find that dynamic attacks are more efficient than their corresponding static attacks, and RB is more destructive than others in all attack graphs while RAD is more destructive than RAS in all attack graphs. Moreover, we propose some suggestions to advance the reliability of the networks according to the simulation results. Additionally, we notice that the damage between ID (RD) and IAD (RAD) is similar due to the large proportion of two-way roads, and we realize that global measures should be employed to estimate the best attack strategy on the basis of that we find the best attack strategy changes with the nodes failure.

  • Delay Insertion Based P2PTV Traffic Localization Considering Peer's Relaying Capability

    Chitapong WECHTAISONG  Hiroaki MORINO  

     
    PAPER-Network

      Pubricized:
    2017/03/23
      Vol:
    E100-B No:10
      Page(s):
    1798-1806

    Recently, P2PTV is a popular application to deliver video streaming data over the Internet. On the overlay network, P2PTV applications create logical links between pairs of peers considering round trip time (RTT) without physical network consideration. P2PTV packets are shared over a network without localization awareness which is a serious problem for Internet Service Providers (ISPs). A delay-insertion-based traffic localization scheme was proposed for solving this problem. However, this scheme sometimes leads the newly joining peer to download streaming traffic from a local neighbor peer which has only scarce upload bandwidth. This paper proposes a novel scheme of delay-insertion-based traffic localization in which the router estimates relay capability to each relay peer candidate and leads the newly joining peer to connect to a neighbor peer with sufficient performance for relaying video data. Parameters were evaluated for the optimized condition in the relay capability estimation process. In addition, experiments conducted on a real network show that our proposed scheme can prevent the newly joining peer from downloading video data from peers with insufficient relay capability and maintain video quality close to normal in a P2PTV system while ensuring efficient traffic localization at the level of the Autonomous System (AS) network.

  • Optical Networking Paradigm: Past, Recent Trends and Future Directions Open Access

    Eiji OKI  Naoya WADA  Satoru OKAMOTO  Naoaki YAMANAKA  Ken-ichi SATO  

     
    INVITED SURVEY PAPER-Fiber-Optic Transmission for Communications

      Pubricized:
    2017/03/22
      Vol:
    E100-B No:9
      Page(s):
    1564-1580

    This paper presents past and recent trends of optical networks and addresses the future directions. First, we describe path networks with the historical backgrounds and trends. path networks have advanced by using various multiplexing technologies. They include time-division multiplexing (TDM), asynchronous transfer mode (ATM), and wavelength-division multiplexing (WDM). ATM was later succeeded to multi-protocol label switching (MPLS). Second, we present generalized MPLS technologies (GMPLS). In GMPLS, the label concept of MPLS is extended to other labels used in TDM, WDM, and fiber networks. GMPLS enables network operators to serve networks deployed by different technologies with a common protocol suite of GMPLS. Third, we describe multi-layer traffic engineering and a path computation element (PCE). Multi-layer traffic engineering designs and controls networks considering resource usages of more than one layer. This leads to use network resources more efficiently than the single-layer traffic engineering adopted independently for each layer. PCE is defined as a network element that computes paths, which are used for traffic engineering. Then, we address software-defined networks, which put the designed network functions into the programmable data plane by way of the management plane. We describe the evaluation from GMPLS to software defined networking (SDN) and transport SDN. Fifth, we describe the advanced devices and switches for optical networks. Finally, we address advances in networking technologies and future directions on optical networking.

  • A Low Capture Power Test Generation Method Based on Capture Safe Test Vector Manipulation

    Toshinori HOSOKAWA  Atsushi HIRAI  Yukari YAMAUCHI  Masayuki ARAI  

     
    PAPER-Dependable Computing

      Pubricized:
    2017/06/06
      Vol:
    E100-D No:9
      Page(s):
    2118-2125

    In at-speed scan testing, capture power is a serious problem because the high power dissipation that can occur when the response for a test vector is captured by flip-flops results in excessive voltage drops, known as IR-drops, which may cause significant capture-induced yield loss. In low capture power test generation, the test vectors that violate capture power constraints in an initial test set are defined as capture-unsafe test vectors, while faults that are detected solely by capture-unsafe test vectors are defined as unsafe faults. It is necessary to regenerate the test vectors used to detect unsafe faults in order to prevent unnecessary yield losses. In this paper, we propose a new low capture power test generation method based on fault simulation that uses capture-safe test vectors in an initial test set. Experimental results show that the use of this method reduces the number of unsafe faults by 94% while requiring just 18% more additional test vectors on average, and while requiring less test generation time compared with the conventional low capture power test generation method.

  • Affinity Propagation Algorithm Based Multi-Source Localization Method for Binary Detection

    Yan WANG  Long CHENG  Jian ZHANG  

     
    LETTER-Information Network

      Pubricized:
    2017/05/10
      Vol:
    E100-D No:8
      Page(s):
    1916-1919

    Wireless sensor network (WSN) has attracted many researchers to investigate it in recent years. It can be widely used in the areas of surveillances, health care and agriculture. The location information is very important for WSN applications such as geographic routing, data fusion and tracking. So the localization technology is one of the key technologies for WSN. Since the computational complexity of the traditional source localization is high, the localization method can not be used in the sensor node. In this paper, we firstly introduce the Neyman-Pearson criterion based detection model. This model considers the effect of false alarm and missing alarm rate, so it is more realistic than the binary and probability model. An affinity propagation algorithm based localization method is proposed. Simulation results show that the proposed method provides high localization accuracy.

  • Feature Detection Scheme Using Cyclic Prefix (CP) in OFDM; Analytical Method for Basic Performance Characteristics and Applications to Mobile Communication Systems

    Kanshiro KASHIKI  Tomoki SADA  Akira YAMAGUCHI  

     
    PAPER-Wireless Communication Technologies

      Pubricized:
    2017/01/12
      Vol:
    E100-B No:7
      Page(s):
    1064-1074

    This paper presents study results regarding the analytical method for performance characteristics and application scheme, which cover a feature detection scheme using a Cyclic Prefix (CP) that is attached to an OFDM signal. The detection scheme is especially important when used as a sensing technology in advanced systems such as Device-to-Device (D-to-D) or Internet of Things (IoT). Herein, we present several basic performance characteristics of the signal processing involved in feature detection, namely, the Output S/N (Signal-to-Noise power ratio) and probability density functions of the OFDM signal and the noise measured at the output of the feature detector. The Output S/Nis described by an analytical expression and is also examined by conducting a software simulation. An analytical approach is investigated by modeling the spectral density of the OFDM signal and input noise and by executing the mathematical operations such as convolutional integration on the combination of OFDM signal and noise. The analytical results coincide closely with the simulation results. As for the applications to mobile communication system, some methods of the feature detection schemes are addressed. These are an estimation method for the Input C/N (Carrier-to-Noise power ratio) and a system discrimination scheme, especially under the assumption that two OFDM systems using different CP lengths are simultaneously operated in the same frequency. Furthermore, under the condition that two OFDM signals are transmitted in an asynchronous manner, a scheme to estimate their timing offset and signal power ratio is also described.

  • Adaptive Elastic Spectrum Allocation Based on Traffic Fluctuation Estimate under Time-Varying Traffic in Flexible OFDM-Based Optical Networks

    Mirai CHINO  Misato KAMIO  Jun MATSUMOTO  Eiji OKI  Satoru OKAMOTO  Naoaki YAMANAKA  

     
    PAPER-Fiber-Optic Transmission for Communications

      Pubricized:
    2016/12/12
      Vol:
    E100-B No:6
      Page(s):
    962-973

    A flexible orthogonal frequency-division multiplexing optical network enables the bandwidth to be flexibly changed by changing the number of sub-carriers. We assume that users request to dynamically change the number of sub-carriers. Dynamic bandwidth changes allow the network resources to be used more efficiently but each change takes a significant amount of time to complete. Service centric resource allocation must be considered in terms of the waiting time needed to change the number of sub-carriers. If the user demands drastically increase such as just after a disaster, the waiting time due to a chain-change of bandwidth becomes excessive because disaster priority telephone services are time-critical. This paper proposes a Grouped-elastic spectrum allocation scheme to satisfy the tolerable waiting time of the service in an optical fiber link. Spectra are grouped to restrict a waiting time in the proposed scheme. In addition, the proposed scheme determines a bandwidth margin between neighbor spectra to spectra to prevent frequent reallocation by estimating real traffic behavior in each group. Numerical results show that the bandwidth requirements can be minimized while satisfying the waiting time constraints. Additionally measurement granularity and channel alignment are discussed.

  • Wavelength Analysis Using Equivalent Circuits in a Fast and Slow Wave Waffle-Iron Ridge Guide

    Hideki KIRINO  Kazuhiro HONDA  Kun LI  Koichi OGAWA  

     
    PAPER

      Vol:
    E100-B No:2
      Page(s):
    219-226

    In this paper we use equivalent circuits to analyze the wavelengths in a Fast and Slow wave Waffle-iron Ridge Guide (FS-WRG). An equivalent circuit for the transverse direction is employed and the transverse resonance method is used to determine the fast wave wavelength. Another equivalent circuit, for the inserted series reactance in the waveguide, is employed for the fast and slow wave wavelength. We also discuss the physical system that determines the wavelengths and the accuracy of this analysis by comparing the wavelengths with those calculated by EM-simulation. Furthermore, we demonstrate use of the results obtained in designing an array antenna.

  • Logic-Path-and-Clock-Path-Aware At-Speed Scan Test Generation

    Fuqiang LI  Xiaoqing WEN  Kohei MIYASE  Stefan HOLST  Seiji KAJIHARA  

     
    PAPER

      Vol:
    E99-A No:12
      Page(s):
    2310-2319

    Excessive IR-drop in capture mode during at-speed scan testing may cause timing errors for defect-free circuits, resulting in undue test yield loss. Previous solutions for achieving capture-power-safety adjust the switching activity around logic paths, especially long sensitized paths, in order to reduce the impact of IR-drop. However, those solutions ignore the impact of IR-drop on clock paths, namely test clock stretch; as a result, they cannot accurately achieve capture-power-safety. This paper proposes a novel scheme, called LP-CP-aware ATPG, for generating high-quality capture-power-safe at-speed scan test vectors by taking into consideration the switching activity around both logic and clock paths. This scheme features (1) LP-CP-aware path classification for characterizing long sensitized paths by considering the IR-drop impact on both logic and clock paths; (2) LP-CP-aware X-restoration for obtaining more effective X-bits by backtracing from both logic and clock paths; (3) LP-CP-aware X-filling for using different strategies according to the positions of X-bits in test cubes. Experimental results on large benchmark circuits demonstrate the advantages of LP-CP-aware ATPG, which can more accurately achieve capture-power-safety without significant test vector count inflation and test quality loss.

  • Coordinated Ramp Metering for Minimum Waiting Time and Limited Ramp Storage

    Soobin JEON  Inbum JUNG  

     
    PAPER-Intelligent Transport System

      Vol:
    E99-A No:10
      Page(s):
    1843-1855

    Ramp metering is the most effective and direct method to control a vehicle entering a freeway. This study proposes a novel density-based ramp metering method. Existing methods typically use flow data that has low reliability, and they suffer from various problems. Furthermore, when ramp metering is performed based on freeway congestion, additional congestion and over-capacity can occur in the ramp. To solve these problems faced with existing methods, the proposed method uses the density and acceleration data of vehicles on the freeway and considers the ramp status. The experimental environment was simulated using PTV Corporation's VISSIM simulator. The Traffic Information and Condition Analysis System was developed to control the VISSIM simulator. The experiment was conducted between 2:00 PM and 7:00 PM on October 5, 2014, during severe traffic congestion. The simulation results showed that total travel time was reduced by 10% compared to existing metering system during the peak time. Thus, we solved the problem of ramp congestion and over-capacity.

  • Low Cost, High Performance of Coplanar Waveguide Fabricated by Screen Printing Technology Open Access

    Masahiro HORIBE  

     
    INVITED PAPER

      Vol:
    E99-C No:10
      Page(s):
    1094-1099

    This paper presents an innovative fabrication process for a planar circuits at millimeter-wave frequency. Screen printing technology provides low cost and high performance coplanar waveguides (CPW) lines in planar devices operated at millimeter-wave frequency up to 110GHz. Printed transmission lines provide low insertion losses of 0.30dB/mm at 110GHz and small return loss like as impedance standard lines. In the paper, Multiline Thru-Reflect-Line (TRL) calibration was also demonstrated by using the impedance standard substrates (ISS) fabricated by screen printing. Regarding calibration capability validation, verification devices were measured and compare the results to the result obtained by the TRL calibration using commercial ISS. The comparison results obtained by calibration of screen printing ISS are almost the same as results measured based on conventional ISS technology.

  • On the Use of m-Ary Challenges for RFID Distance Bounding Protocol

    Young-Sik KIM  Sang-Hyo KIM  

     
    PAPER-Fundamental Theories for Communications

      Vol:
    E99-B No:9
      Page(s):
    2028-2035

    In this paper, we propose an RFID distance bounding protocol that uses m-ary challenges. Recently, Kim and Avoine proposed two distance bounding protocols with mixed challenges that are pre-determined or random. We generalize the first scheme of Kim and Avoine's random scheme as a distance bounding protocol with m-ary challenges. The generalized formula for success probabilities for mafia fraud and distance fraud attacks is derived. Our scheme using m-ary challenges reduces the mafia fraud success probability from (3/4)n for m=2 to (7/16)n for m=4 and the distance fraud success probability from $(1- rac 1 4 cdot P_r)^n$ for m=2 to $(1 - rac {189}{256} cdot P_r)^n$ for m=4, where Pr is the probability that a challenge is random.

  • Modelling Load Balancing Mechanisms in Self-Optimising 4G Mobile Networks with Elastic and Adaptive Traffic

    Mariusz GŁĄBOWSKI  Sławomir HANCZEWSKI  Maciej STASIAK  

     
    PAPER-Fundamental Theories for Communications

      Vol:
    E99-B No:8
      Page(s):
    1718-1726

    This article describes an approximate model of a group of cells in the wireless 4G network with implemented load balancing mechanism. An appropriately modified model of Erlang's Ideal Grading is used to model this group of cells. The model makes it possible to take into account limited availability of resources of individual cells to multi-rate elastic and adaptive traffic streams generated by Erlang and Engset sources. The developed solution allows the basic traffic characteristics in the considered system to be determined, i.e. the occupancy distribution and the blocking probability. Because of the approximate nature of the proposed model, the results obtained based on the model were compared with the results of a digital simulation. The present study validates the adopted assumptions of the proposed model.

101-120hit(873hit)