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[Author] Tetsuya YAMAMURA(4hit)

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  • Flexible Allocation of Optical Access Network Resources Using Constraint Satisfaction Problem

    Kenichi TAYAMA  Shiro OGASAWARA  Tetsuya YAMAMURA  Yasuyuki OKUMURA  

     
    PAPER-Network Management/Operation

      Vol:
    E90-B No:7
      Page(s):
    1674-1681

    A method for flexibly allocating and reallocating optical access network (OAN) resources, including fibers and equipment, using the constraint satisfaction problem (CSP) is described. OAN resource allocation during service delivery provisioning involves various input conditions and allocation sequences, so an OAN resource allocation method has to support various workflow patterns. Furthermore, exception processing, such as reallocating OAN resources once they are allocated, is inevitable, especially during the spread of service using optical fiber and during the deployment of an optical access network. However, it is almost impossible to describe all workflow patterns including exception processes. Improving the efficiency of these exception processes, as well as that of the typical processes, is important for reducing the service delivery time. Describing all these patterns and process flows increases development cost. The CSP can be used to search for solutions without having to fix the process sequence and input conditions beforehand. We have formulated the conditions for OAN resource allocation and reallocation as a CSP. Use of this method makes it possible to handle various allocation workflow patterns including exception processes. Evaluation of the solution search time demonstrated its feasibility.

  • An Implementation of the TMN-Based Integrated Management Display System

    Hiroshi TOHJO  Tetsuya YAMAMURA  Tetsuaki GOTO  

     
    PAPER-System architecture

      Vol:
    E80-B No:10
      Page(s):
    1421-1428

    In order to efficiently conduct the complex operations of network OpSs (Operation Systems), we introduce the TMN-based Integrated Management Display System (IMD). IMD is able to control the display of windows monitoring individual operations on multiple screens such as project monitors. In this paper, we describe an implementation of the IMD and experimental results. This implementation consists of the Multi-Screen Control System (MSS), Multi-Screen Agent System (MSA) and Multi-Screen Manager System (MSM). MSA controls MSS directly via proprietary protocols. MSM manages MSA via the TMN Interface. MSA is modeled using the GDMO (Guidelines for the Definition of Managed Objects). Moreover, in order to realize cooperation with other OpSs, MSM is based on TMN. We confirm that MSM interworks with ATMOS (ATM Transport Network Operation System) and develop an alarm surveillance system for ATMOS using IMD at in an OpS-Room. Experiments verify that MSA can be controlled by MSM following the alarms emitted from the real network equipment of the ATM Transport Network. As a result, the operators can comprehend the operations information more quickly than is possible with the conventional system. By using the TMN-based Integrated Management Display System (IMD), operations such as alarm surveillance can be performed more efficiently.

  • Application of Liquid Crystal Polymer Materials to Optical Fiber Cables

    Takamasa YASHIRO  Hisashi MURATA  Tetsuya YAMAMURA  Tsutomu TANABE  

     
    LETTER-Cables and Waveguides

      Vol:
    E70-E No:1
      Page(s):
    11-13

    Application of liquid crystal polymer (LCP) materials, having a higher Young's modulus than usual plastic materials, to optical fiber jackets and unit central members has been investigated. Novel optical fiber units thus constructed are found to exhibit ultra low thermal expansion coefficient and no optical loss change within 6060 range. Zero thermal expansion coefficient can be achieved over the wide temperature range by suitable combination of LCP materials with high and medium Young's moduli.

  • A Construction Manager System over an ATM Transport Network Operation System Verification of the Basic Technique of Flowthrough Operation in Configuration Management

    Hiroshi TOHJO  Tetsuya YAMAMURA  

     
    PAPER-System Implementation

      Vol:
    E80-B No:6
      Page(s):
    833-840

    We have studied the flowthrough operation to simplify operation processes and to promote the efficiency of operation flows. In this paper, we introduce the Construction Manager System (CMS) that cooperates with the ATM Transport Network Operation System (ATMOS). This system directs the construction processes using the construction tickets newly defined by the GDMO (Guidelines for the Definitions of Managed Objects); these tickets and action scenarios are prepared inside the SMS (Scenario Management System). We confirm that CMS can perform construction management using the construction tickets instead of the traditional off-line communications such as the telephone and the facsimile. Furthermore, because CMS cooperates with ATMOS, it is able to manage actual network elements (NEs) and conduct board costruction processes by using construction tickets. Moreover, CMS can confirm that the construction processes of the actual NEs have actually been executed through the Q3 interface. As a result, we verify the basic technique for flowthrough operation for configuration management.