September 2010 Vol. 8 No. 9

Front-line Researchers

• Tatsuaki Okamoto, NTT Fellow, NTT Information Sharing Platform Laboratories

  

  Fascinated with Cryptography

  Overview
  We asked world-renowned cryptography researcher Tatsuaki Okamoto, an NTT Fellow, to explain why cryptography research is important, tell us about his experiences and future research ambitions, and pass on some words of encouragement to young researchers.

Special Feature on Technical Solutions to Real-world Problems

• Wireless Local Area Network Monitoring Tool

  

  Abstract
  This article introduces a wireless local area network (WLAN) monitoring tool that can simplify the monitoring of interference from industrial, scientific, and medical devices and allow the selection of a wireless channel with minimal interference from such devices to stabilize WLAN communications. This monitoring tool was developed by NTT EAST as an additional function to its WLAN troubleshooting tool, AirSpector, which can perform various types of troubleshooting for WLAN environments.

• Probing Method for Determining Position of Optical-fiber-cable Damage inside a Conduit

  

  Abstract
  This article introduces a method for probing faulty optical fiber cables by using a combination of conventional measuring devices: an optical time domain reflectometer (OTDR) and a pipe camera. It can easily and rapidly identify the position and cause of a fault in an optical fiber cable located within an underground conduit at a distance of up to about 990 m from an NTT building. A field experiment identified two faults in a deliberately laid cable with an artificial cut-fiber fault and observed light leaking from one of them, demonstrating the method’s effectiveness.

• VDSL Fault Troubleshooting Tools

  

  Abstract
  The Technical Assistance and Support Center at NTT EAST has developed a very-high-speed digital subscriber line (VDSL) tester and VDSL handheld recorder on the basis of feedback received from its fault-repair department. These devices are used as tools for troubleshooting faults in the VDSL wiring section inside buildings as part of the B FLET’S broadband-connection service.

• Water Penetration Inspection Methods for Remote Terminal Boxes

  

  Abstract
  This article describes the problem of water entering remote terminal boxes and corresponding inspection methods.

Letters

• Traffic Engineering Using Overlay Network

  

  Abstract
  We present a method of controlling the traffic of individual services by using an overlay network, which lets us flexibly add various functionalities. The overlay network provides control functionalities such as for constructing an overlay network topology for each service, calculating the optimal route for its quality of service (QoS), and caching content to reduce the amount of traffic. By applying traffic engineering taking into account each service’s QoS requirements, this overlay network can overcome the problem of indiscriminate QoS degradation when the network becomes congested due to a sudden increase in traffic for a particular service.

Global Standardization Activities

• Overview and Status of Focus Group on Future Networks at ITU-T

  

  Abstract
  The Focus Group on Future Networks (FG-FN) was established by Study Group 13 (SG13) of the International Telecommunication Union, Telecommunication Standardization Sector (ITU-T) in 2009. Its main role is to share discussions on future networks and ensure a global common understanding about them. This article describes the current status and activities of FG-FN.

External Awards/Papers Published in Technical Journals and Conferences Proceedings

• External Awards/Papers Published in Technical Journals and Conferences Proceedings