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[Author] Daisuke ISHII(12hit)

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  • Experiment on Point-to-Multipoint VLAN Path Establishment on the Overlay-Model-Based GMPLS-Controlled Wide Area Ethernet

    Kou KIKUTA  Daisuke ISHII  Satoru OKAMOTO  Naoaki YAMANAKA  

     
    LETTER-Network System

      Vol:
    E95-B No:10
      Page(s):
    3302-3306

    We report the first successful experiment on Point-to-Multipoint (P2MP) VLAN path establishment on the overlay-model-based GMPLS-controlled wide area Ethernet. To support the overlay model, P2MP VLAN path signaling with egress output port indication is proposed and implemented. It is confirmed that our extended RSVP-TE software can correctly establish P2MP VLAN paths in the overlay-model network.

  • Automatic Scale Detection for Contour Fragment Based on Difference of Curvature

    Kei KAWAMURA  Daisuke ISHII  Hiroshi WATANABE  

     
    PAPER-Pattern Recognition

      Vol:
    E94-D No:10
      Page(s):
    1998-2005

    Scale-invariant features are widely used for image retrieval and shape classification. The curvature of a planar curve is a fundamental feature and it is geometrically invariant with respect it the coordinate system. The curvature-based feature varies in position when multi-scale analysis is performed. Therefore, it is important to recognize the scale in order to detect the feature point. Numerous shape descriptors based on contour shapes have been developed in the field of pattern recognition and computer vision. A curvature scale-space (CSS) representation cannot be applied to a contour fragment and requires the tracking of feature points. In a gradient-based curvature computation, although the gradient computation considers the scale, the curvature is normalized with respect to not the scale but the contour length. The scale-invariant feature transform algorithm that detects feature points from an image solves similar problems by using the difference of Gaussian (DoG). It is difficult to apply the SIFT algorithm to a planar curve for feature extraction. In this paper, an automatic scale detection method for a contour fragment is proposed. The proposed method detects the appropriate scales and their positions on the basis of the difference of curvature (DoC) without the tracking of feature points. To calculate the differences, scale-normalized curvature is introduced. An advantage of the DoC algorithm is that the appropriate scale can be obtained from a contour fragment as a local feature. It then extends the application area. The validity of the proposed method is confirmed by experiments. The proposed method provides the most stable and robust scales of feature points among conventional methods such as curvature scale-space and gradient-based curvature.

  • Connection Setup Signaling Scheme with Flooding-Based Path Searching for Diverse-Metric Network

    Ko KIKUTA  Daisuke ISHII  Satoru OKAMOTO  Eiji OKI  Naoaki YAMANAKA  

     
    PAPER-Network

      Vol:
    E95-B No:8
      Page(s):
    2600-2609

    Connection setup on various computer networks is now achieved by GMPLS. This technology is based on the source-routing approach, which requires the source node to store metric information of the entire network prior to computing a route. Thus all metric information must be distributed to all network nodes and kept up-to-date. However, as metric information become more diverse and generalized, it is hard to update all information due to the huge update overhead. Emerging network services and applications require the network to support diverse metrics for achieving various communication qualities. Increasing the number of metrics supported by the network causes excessive processing of metric update messages. To reduce the number of metric update messages, another scheme is required. This paper proposes a connection setup scheme that uses flooding-based signaling rather than the distribution of metric information. The proposed scheme requires only flooding of signaling messages with requested metric information, no routing protocol is required. Evaluations confirm that the proposed scheme achieves connection establishment without excessive overhead. Our analysis shows that the proposed scheme greatly reduces the number of control messages compared to the conventional scheme, while their blocking probabilities are comparable.

  • Template-Based Monte-Carlo Test-Suite Generation for Large and Complex Simulink Models Open Access

    Takashi TOMITA  Daisuke ISHII  Toru MURAKAMI  Shigeki TAKEUCHI  Toshiaki AOKI  

     
    PAPER

      Vol:
    E103-A No:2
      Page(s):
    451-461

    MATLAB/Simulink is the de facto standard tool for the model-based development (MBD) of control software for automotive systems. A Simulink model developed in MBD for real automotive systems involves complex computation as well as tens of thousands of blocks. In this paper, we focus on decision coverage (DC), condition coverage (CC) and modified condition/decision coverage (MC/DC) criteria, and propose a Monte-Carlo test suite generation method for large and complex Simulink models. In the method, a candidate test case is generated by assigning random values to the parameters of signal templates with specific waveforms. We try to find contributable candidates in a plausible and understandable search space, specified by a set of templates. We implemented the method as a tool, and our experimental evaluation showed that the tool was able to generate test suites for industrial implementation models with higher coverages and shorter execution times than Simulink Design Verifier. Additionally, the tool includes a fast coverage measurement engine, which demonstrated better performance than Simulink Coverage in our experiments.

  • Multi-Domain VLAN Path Signaling Method Having Tag Swapping Function for GMPLS Controlled Wide Area Layer-2 Network

    Kou KIKUTA  Masahiro NISHIDA  Daisuke ISHII  Satoru OKAMOTO  Naoaki YAMANAKA  

     
    LETTER-Switching for Communications

      Vol:
    E92-B No:4
      Page(s):
    1353-1356

    A multi-domain GMPLS layer-2 switch capable network with VLAN tag swapping is demonstrated for the first time. In this demonstration, we verify three new features, establishing path with designating VLAN IDs, swapping VLAN ID on prototype switch, and management of VLAN IDs per domain. Using those three features, carrier-class Ethernet backbone networks which supports path route designation in multi-domain network can be established.

  • Highly Energy Efficient Layer-3 Network Architecture Based on Service Cloud and Optical Aggregation Network

    Hidetoshi TAKESHITA  Daisuke ISHII  Satoru OKAMOTO  Eiji OKI  Naoaki YAMANAKA  

     
    PAPER

      Vol:
    E94-B No:4
      Page(s):
    894-903

    The Internet is an extremely convenient network and has become one of the key infrastructures for daily life. However, it suffers from three serious problems; its structure does not suit traffic centralization, its power consumption is rapidly increasing, and its round-trip time (RTT) and delay jitter are large. This paper proposes an extremely energy efficient layer-3 network architecture for the future Internet. It combines the Service Cloud with the Cloud Router and application servers, with the Optical Aggregation Network realized by optical circuit switches, wavelength-converters, and wavelength-multiplexers/demultiplexers. User IP packets are aggregated and transferred through the Optical Aggregation Network to Cloud transparently. The proposed network scheme realizes a network structure well suited to traffic centralization, reduces the power consumption to 1/20-1/30 compared to the existing Internet, reduces the RTT and delay jitter due to its simplicity, and offers easy migration from the existing Internet.

  • Performance Evaluation of TCP/IP over SCTP/IP Parallel Networking with Parallel Route Transmission

    Shota YAMADA  Daisuke ISHII  Satoru OKAMOTO  Naoaki YAMANAKA  

     
    LETTER-Network

      Vol:
    E94-B No:8
      Page(s):
    2394-2396

    In this paper, Transmission Control Protocol/Internet Protocol (TCP/IP) over Stream Control Transmission Protocol (SCTP)/IP parallel transmission system is proposed to realize large TCP/IP throughput. The proposed system enables SCTP/IP connection between switches by protocol stacking. The proposed system is implemented on a software switch to evaluate its performance. The evaluation result indicates that proposed system can achieve 90% throughput compared with serial transmission when the delay difference among parallel routes is 20 msec.

  • Semi-Parametric Effective-Bandwidth Estimator Based on Buffer Measurements

    Shigeo SHIODA  Daisuke ISHII  

     
    PAPER-Network

      Vol:
    E87-B No:12
      Page(s):
    3627-3636

    The notion of effective bandwidth provides an elegant and powerful mathematical basis for the provision of QoS-assured services over IP networks. In this paper, we propose a semi-parametric estimator of effective bandwidth, called Gaussian estimator using buffer masurement, for superposition of sources in IP networks. In contrast to most existing proposals concerning the effective bandwidth estimator, our proposal works based on a small set of measurements of the workload in the buffer of a router. We analytically show the property of the proposed estimator with respect to the dependence on the service rate. We provide numerical results to show that our proposed estimator is more accurate than estimators that rely only on the amount of traffic from sources.

  • Interoperability Experiment of VLAN Tag Swapped Ethernet and Transmitting High Definition Video through the Layer-2 LSP between Japan and Belgium Open Access

    Sho SHIMIZU  Wouter TAVERNIER  Kou KIKUTA  Masahiro NISHIDA  Daisuke ISHII  Satoru OKAMOTO  Didier COLLE  Mario PICKAVET  Piet DEMEESTER  Naoaki YAMANAKA  

     
    LETTER-Network

      Vol:
    E93-B No:3
      Page(s):
    736-740

    The first global interoperability experiment of GMPLS controlled Ethernet with VLAN tag swapping between two different implementations is successfully demonstrated. High definition video streaming is realized through a newly established Layer 2 Label Switched Path (L2-LSP). The results of this experiment can be applied to designing reliable Layer 2 networks.

  • FOREWORD Open Access

    Daisuke ISHII  

     
    FOREWORD

      Vol:
    E105-A No:5
      Page(s):
    787-787
  • Monitoring Temporal Properties Using Interval Analysis

    Daisuke ISHII  Naoki YONEZAKI  Alexandre GOLDSZTEJN  

     
    INVITED PAPER

      Vol:
    E99-A No:2
      Page(s):
    442-453

    Verification of temporal logic properties plays a crucial role in proving the desired behaviors of continuous systems. In this paper, we propose an interval method that verifies the properties described by a bounded signal temporal logic. We relax the problem so that if the verification process cannot succeed at the prescribed precision, it outputs an inconclusive result. The problem is solved by an efficient and rigorous monitoring algorithm. This algorithm performs a forward simulation of a continuous-time dynamical system, detects a set of time intervals in which the atomic propositions hold, and validates the property by propagating the time intervals. In each step, the continuous state at a certain time is enclosed by an interval vector that is proven to contain a unique solution. We experimentally demonstrate the utility of the proposed method in formal analysis of nonlinear and complex continuous systems.

  • Scalable Active Optical Access Network Using Variable High-Speed PLZT Optical Switch/Splitter

    Kunitaka ASHIZAWA  Takehiro SATO  Kazumasa TOKUHASHI  Daisuke ISHII  Satoru OKAMOTO  Naoaki YAMANAKA  Eiji OKI  

     
    PAPER

      Vol:
    E95-B No:3
      Page(s):
    730-739

    This paper proposes a scalable active optical access network using high-speed Plumbum Lanthanum Zirconate Titanate (PLZT) optical switch/splitter. The Active Optical Network, called ActiON, using PLZT switching technology has been presented to increase the number of subscribers and the maximum transmission distance, compared to the Passive Optical Network (PON). ActiON supports the multicast slot allocation realized by running the PLZT switch elements in the splitter mode, which forces the switch to behave as an optical splitter. However, the previous ActiON creates a tradeoff between the network scalability and the power loss experienced by the optical signal to each user. It does not use the optical power efficiently because the optical power is simply divided into 0.5 to 0.5 without considering transmission distance from OLT to each ONU. The proposed network adopts PLZT switch elements in the variable splitter mode, which controls the split ratio of the optical power considering the transmission distance from OLT to each ONU, in addition to PLZT switch elements in existing two modes, the switching mode and the splitter mode. The proposed network introduces the flexible multicast slot allocation according to the transmission distance from OLT to each user and the number of required users using three modes, while keeping the advantages of ActiON, which are to support scalable and secure access services. Numerical results show that the proposed network dramatically reduces the required number of slots and supports high bandwidth efficiency services and extends the coverage of access network, compared to the previous ActiON, and the required computation time for selecting multicast users is less than 30 msec, which is acceptable for on-demand broadcast services.