May 2018 Vol. 16 No. 552018

https://www.ntt-review.jp/archive/2018/201805.html

Feature Articles
NTT Group Security Confronts
Escalating Cyberattacks
Research and Development of Advanced Security
Measures to Protect Customers from Sophisticated andLarge-scale Cyberattacks
Collecting, Analyzing, and Leveraging Threat Intelligenceat NTT-CERT
Security Business Solutions for Customer Needs
Cyberattack Countermeasure Technology to Support
NTT’s Security BusinessFeature Articles
NTT Group Security Confronts Escalating Cyberattacks

Research and Development of Advanced Security Measures
to Protect Customers from Sophisticated and Large-scaleCyberattacks▼Abstract

The Feature Articles in this issue introduce recent trends andcase studies of ever-escalating cyberattacks that arebecoming increasingly sophisticated and large in scale, plus
issues and needs in the security business of NTT Group
companies. Additionally, new needs are arising for security
measures for customers. These articles introduce theresearch and development of advanced technologies deemednecessary for countering cyberattacks and increasing
business competitiveness.

Regular Articles

Digital-preprocessed Analog-multiplexed Digital-to-analog
Converter for Ultrahigh-speed Optical Transmitter▼Abstract

Regular Articles
Digital-preprocessed Analog-multiplexed Digital-to-analog Converter for Ultrahigh-speed OpticalTransmitter
Satellite Communications Modem Unit COM-U—Enhanced Maintenance, Operations, andSpectrum Utilization Efficiency of Satellite Transponders for Remote Island Satellite
Communications and Disaster Relief Satellite Communications

Global Standardization Activities
Trends in Standardization of Blockchain Technology by ISO/TC 307

Information
Report on NTT R&D Forum 2018

Short Reports
Japan-Taiwan Joint Experiment Successfully Demonstrates White-box Based Carrier-grade
Networking—International Service Provider Collaboration in Software-defined Networking Pushes
Forward IP Packet Transport to Employ Commodity Products

We have developed technology to extend the analog
bandwidth of digital-to-analog converters (DACs), which areessential in advanced high-speed optical transmitters. We
used a digital preprocessor, two sub-DACs, and an analog
multiplexer to generate arbitrary signals with a bandwidthnearly twice that of each sub-DAC. This technology was used
to successfully demonstrate various high-speedtransmissions, including an intensity-modulated directly
detected transmission at a record-high data rate of 250 Gbit/s.

Satellite Communications Modem Unit COM-U—Enhanced
Maintenance, Operations, and Spectrum Utilization Efficiency
of Satellite Transponders for Remote Island Satellite
Communications and Disaster Relief Satellite Communications▼Abstract

A major advantage of satellite communications is theability to implement communication networks virtually
anywhere in Japan very simply. The NTT Group has beenutilizing satellite communications to provide services insituations where optical fiber, mobile telephony, and otherterrestrial facilities are impractical: remote islands,
offshore areas, and stricken regions where people havebeen forced to temporarily flee in the face of earthquakes and other natural disasters. The Group continues
to pursue research and development on satellite systems to make them more efficient and advanced. Here
we present an overview of NTT’s new satellite communications modem unit called COM-U (satellite
circuit-terminating common unit), that markedly improves the spectrum utilization efficiency of satellite
transponders and the maintenance and operations of satellite communications used for remote island anddisaster relief satellite communications.