NTT Technical Review
March 2016 Vol. 14 No. 3
View from the Top
Seizo Onoe, Executive Vice President and Chief Technology Officer,
NTT DOCOMO

Front-line Researchers
William John Munro, Senior Research Scientist, NTT Basic ResearchLaboratories

Feature Articles: New Generation Network Platform andAttractive Network Services
Development towards Building a New Generation Network Platform andAttractive Network Services
SDN Software Switch Lagopus and NFV Service Orchestrator vConductor for
Developing SDN/NFVREMOCOP: Remote Collaboration Platform for a Next Generation Remote
Collaboration Support System
Smart CPE R&D for Highly Intelligent Enterprise Networks
Distributed Time Series Data Management and Analysis

Regular Articles
Development of Highly Efficient Group Modem Module and Turbo Codec
Module for Next Generation Satellite Communication Systems

Global Standardization Activities
Standardization Activities on EMC for Telecommunication in ITU-T SG5

New NTT Colleagues
We welcome our newcomers to the NTT Group

External Awards/Papers Published in Technical Journals
and Conference Proceedings
External Awards/Papers Published in Technical Journals and Conference
Proceedings

View from the Top

Changing the World for the Better!
R&D as the Engine Driving
Continued Corporate Growth
Seizo Onoe
Executive Vice President and Chief
Technology Officer, NTT DOCOMO
Overview

NTT DOCOMO is the source of much innovative technology in themobile industry, and with 2020 in view, it has already set in motion the
research and development of 5G, the fifth-generation mobile communications system. We asked Seizo Onoe, NTT DOCOMO Executive Vice President and Chief Technology Officer, how the company is surviving thehighly competitive environment and what it aims to achieve by making
maximum use of the company’s strengths.
Keywords: 5G, LTE (Long Term Evolution), R&D

Leveraging close contact with customers todevelop new services—Mr. Onoe, please tell us about the business environment surrounding NTT DOCOMO.
The last few years have seen severe competition in
the business environment, but financial results for thethird quarter of fiscal year 2015 showed an operating
revenue of 3383.5 billion yen and an operating
income of 685.5 billion yen, or a year-on-yearincrease of 1.7% and 16.8%, respectively, showingthat the company has achieved two consecutive quarters of growth in both revenue and income. The Smart
Life domain has been expanding favorably, and costmanagement such as in the area of capital investments is becoming increasingly more efficient. At the
beginning of this fiscal year, NTT DOCOMO rolled
out its “+d” initiative that aims to deliver new value
to its customers through co-creation with partners.
The plan is to make significant contributions to soci1

ety under the themes of “solving social issues” and“revitalizing regional economies.”
Combining the strengths of our partners with thediverse business assets of NTT DOCOMO creates
new value. Being in charge of research and development (R&D), I also think in terms of “+d” from an
R&D perspective. When we hear the words “NTTDOCOMO asset,” perhaps the first thing that comesto mind is a business-like asset such as a customer
base, but a technology asset can be just as valuable.
Co-creation on the R&D side is already occurring in
unexpected areas and producing results toward new
business opportunities.
To give an example, NTT DOCOMO’s naturallanguage dialog platform technology developed for
the Shabette Concier voice-agent service and otherapplications has been incorporated in the OHaNAS
interactive conversational toy robot developed jointlywith TOMY Company, Ltd. The business environment is still as competitive as ever, but I would like tocreate a virtuous cycle in which the growth of NTT
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DOCOMO itself results in the continuous provisionof even better services for our customers.
—NTT DOCOMO has prospered despite the severelycompetitive environment—where do its strengths now
lie?
Being a corporate enterprise, NTT DOCOMO must
continue to generate profits, but on the other hand, it
must also invest in the future. In a highly competitiveenvironment, investment in the future would tend to
be restricted, but I believe that the engine for achieving continued corporate growth into the future is
R&D. For the past few years, we have been reviewing
the methods used in R&D and working to make
operations more cost-effective, and it is exactly
because there are restrictions here that we have had tocome up with new ideas and approaches. As a result,
I believe that we have restructured ourselves in a waythat enables us to produce R&D results in an ongoingand efficient manner.
Nevertheless, determining how much to invest andwhat to research in advance is difficult, to say theleast. As you know, the range of R&D at NTT
DOCOMO is quite broad, spanning the improvement
and expansion of existing services as well as network
operations and technical support. While it is necessary to continue our existing technology development
efforts building upon past results, I also intend toprepare a growth engine that looks five years andmore into the future taking technology trends into
account.
Regarding the infrastructure development, NTT
DOCOMO is focusing on the fifth-generation mobile
communications system (5G), enhancement of the
LTE-Advanced system, and network functions virtualization (NFV). We are proud of our role as a global
leader in third- and fourth-generation (3G and 4G)
system development, and we now have our sights set
on deploying 5G services by 2020. In fact, we areconducting experiments and trials in cooperation
with leading global vendors to contribute to the standardization of 5G technology.
The key issue here is how to go about creating newservices. There are great expectations that the Internetof Things, big data, and artificial intelligence (AI)will lead to new business opportunities. NTT
DOCOMO has been involved in this area from early
on, and some services of this type are already being
offered to customers. The natural-language dialog
engine that was first used in Shabette Concier has
undergone further development by incorporating
Vol. 14 No. 3 Mar. 2016

NTT research results to the maximum. These efforts
led to the development of the OHaNAS robot that I
mentioned. In this way, I believe that the way NTT
DOCOMO maintains close contact with customers
when creating new services is a key strength.
Moving forward with a global view 20 years into
the future—contributing to the world with 5G—Where is NTT DOCOMO headed in the years tocome?
As you know, NTT DOCOMO’s origins are in themobile world. Up to the second-generation mobile
communications system, specifications tended to be
fragmented among countries and carriers, but from
3G on, it has been the earnest desire of the mobile
industry to implement a common system worldwide.
In this regard, 3G and LTE certainly played a role inachieving a world standard, but it was NTT DOCOMO
that was recognized as a world leader in this process.
Our R&D achievements are one reason for the highmarks we have received, especially from parties overseas. Government ministers in Europe have been
known to come here to visit our top executives largely because of our R&D. Of course, gaining suchpraise or respect is not our objective. Our aim throughR&D is to make business-related contributions and toprovide our customers with even better services.
On the other hand, the mobile industry on the wholehas a very low reputation worldwide. Despite efforts
at making people’s lives more convenient and contributing to society through mobile communications,the reality is that these efforts are not generally recognized. To rectify this situation, I would like to demonstrate to the world in concrete ways just how usefulmobile technology can be to society and how it can2View from the Top

contribute to the entire world community.
Recently, on the occasion of the Miss International
Beauty Pageant held in Tokyo, we asked contestantsfrom various countries to trial the 5G mobile communications technology. We received many messages
expressing positive reactions such as “I would love tobe able to use 5G in my country soon” and “I want 5G
to change the world for the better,” even from contestants representing regions having a relatively low
penetration of mobile phones. Such reactions madeus feel that 5G is generating great expectations froma wide range of people throughout the world, and wecame away with a strong sense of responsibility tocontribute to the world through 5G technology.
To date, the mobile industry has witnessed the birthof a new generation of technology about every ten
years, and the immediate target is the launch of 5G in
2020. In Japan’s advanced mobile communications
market, the 1G and 2G systems discontinued operations after 20 years, reflecting a relatively quick transition in technology. Worldwide, however, history has
shown that the diffusion of a certain generation ofmobile technology peaks at the 20-year mark. We cansay, therefore, that the development of a new generation of technology brings maximum benefit to theworld 20 years later.
Technology trends in terms of infrastructure evolution can be predicted five or ten years into the future
to some extent. However, I can honestly say that predicting the state of services five years from now isdifficult. There are those who simply say that innovation does not occur in large corporations. However, I
believe that services are about to become a very

3

important area, and it’s my aim to create an environment to achieve a lot of innovation at NTT DOCOMO.
With the aim of creating new services using a mechanism different from that used for existing services, I
have made organizational changes and put into placea new system and development process. Here, an
open development environment is crucial, and we areworking on creating new value centered about passionate and enthusiastic developers through collaboration with parties on the outside.
Returning to the topic of 5G, I can say that initiating
studies on new generation technology generally gives
rise to negative reactions, as in questioning the needfor changing to a new generation when the current
generation is still generating revenue and pointing outthat constructing a new infrastructure will incur massive expenses. When studies on 3G were beginning,some people would ask, “What would a data rate of
2 Mbit/s be used for?” and in the case of LTE, a common question was “Is a rate of 100 Mbit/s reallynecessary?” NTT DOCOMO takes the initiative intechnology development and makes investments
where needed. Once a person has been placed in apleasant environment and becomes accustomed to it,
there’s no turning back! When a more convenientenvironment is provided, a virtuous cycle will arise inwhich users come up with usage methods appropriate
to that environment. In this way, people are now
enjoying one of the world’s leading mobile environments that we created. There is much excitement
about 5G at such an early stage that the standardization discussion has not yet started. This is more thanwe expected, but in the period leading up to 2020, mygoal is to make steady progress in developing 5G
technology without losing any of that excitement.
There is one more thing concerning a dream ofmine that I would like to purposely express to theoutside world. I believe that the base technology ofmobile phone systems, that is, cellular technology,
will come to be used in all sorts of use cases and will
eventually become the dominant communication
technology. For the time being, we can expect a number of technologies to be used and operated in acomplementary and coordinated manner, but mydream is that they will all converge to cellular technology one day. On the other hand, as we look out
over a long time span of say 30 years, the reality isthat cellular technology might again diverge intosome different technologies. Over the next five years,
however, I am confident that the various technologies
now in use will converge to LTE-based cellular technology.
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Easily achieved results soon becomecommonplace. Set targets that even you may havedoubts about!
—Mr. Onoe, you are sometimes called the “father ofLTE.” Can you leave us with a message for the engineers working under you and all NTT DOCOMO
employees?
I would be happy to. The emotional argument that“a person with passion can do anything” certainly is
not true all the time, but it is very important that you
continue to bring passion to your work. While thisdepends somewhat on each person’s temperament,
having a desire to seek out challenging themes andbig dreams with persistence is important in an engineer. Looking back at myself in the past, I would saythat perhaps I was like that, but only in the sense that
I would become totally absorbed in the problem
before me. However, through experience, I came tounderstand the importance of setting somewhat hightargets. If you set a low hurdle for yourself, you will
be able to achieve something very soon, but whatever
it is that you developed will soon become commonplace and conventional.
I believe that “things that appear impossible” and“things for which people have doubts about” are ideal
as five-year targets. In relation to 5G, I will usuallytell my research team to achieve something difficultthat even I myself have doubts about it. For example,
I have told them that I want us to aim for a cellular
system that can deliver signals up to a distance of
1 km even if using high frequency bands, despite thefact that I actually feel that only half that distance isfeasible. In my experience, when I become absorbed
in a project while thinking “there is no way that thiscan be done,” I have sometimes experienced utter
surprise when it turns out to be doable, exclaiming“What? It worked!”
The capability of doing anything on our own issometimes referred to as being in the NTT Group’s
DNA. However, we will enter an era in which we cannot survive if we are not quick to adapt to changes invendor and operator relations and in technologies andecosystems while thinking closely about what weourselves should be doing and where we should focus
our energy. In today’s world, technology tends to becontrolled by vendors, but displeasure with this situation can be heard from operators. I want NTT
DOCOMO to continue to have a big impact on theworld and to be obsessed in a good way about doing
so. In this endeavor, it is crucial that we know ourVol. 14 No. 3 Mar. 2016

customers better and have a global perspective. It is
nonsense to think about what to create by looking
only at Japan without learning about things going onin the outside world. With these ideas in mind, I
would like all engineers and employees to think forthemselves and let their opinions be known and to
adopt the spirit of a world leader in their field.
Finally, I would like us to develop close links with
the R&D departments within the NTT Group. We can
expect NTT laboratories to have top-level technologies in the security field and elsewhere. I want tocreate services that change the world through intragroup collaboration that facilitates the mutual use of
superb technologies. We need to form closer andstronger ties. And there are key areas being driven by
NTT DOCOMO, too such as AI-based interactive andtranslation technologies, platforms for locationinformation services, and NFV. Going forward, I
want us to develop strong collaborative practices tomaximize the value of the entire NTT Group!
Interviewee profile
Career highlights
Seizo Onoe joined Nippon Telegraph andTelephone Public Corporation (now NTT) in
1982. After entering the company, he took on the
R&D of mobile communications systems. He
became NTT DOCOMO Senior Vice President
and Managing Director of the R&D Strategy
Department in 2008 and Executive Vice President,
a member of the Board of Directors, and Managing
Director of the R&D Center in 2012. He assumed
his current position in July 2014 while retaining
his position as a member of the Board of
Directors.

4

Front-line Researchers

Research Isn’t Evolution—It’s Revolution!
William John Munro
Senior Research Scientist, NTT Basic
Research Laboratories
Overview

In this issue, we welcome Dr. William J. Munro, the first nonJapanese group leader within NTT laboratories, as our front-line
researcher. Bill passionately tells us about quantum physics,
which has the potential to bring great change to the world, and its
application to the field of information and communications. He
also tells us why out of all the research institutes in the world, hedecided to join NTT laboratories, and how he approaches research
to produce innovative results.
Keywords: quantum physics, quantum device, research

Overthrowing established theory and envisioning
quantum networks of the future—Dr. Munro, please tell us about your current
research.
Well, I am researching the creation of new quantum
technology through the exploration of the uniqueproperties of quantum physics and the fundamental
limits it has on information processing. For example,
my pen consists of a variety of small parts (the case,spring, etc.,…). Each of these parts is made of smaller parts, some too small for the human eye to see(micron sized for instance). If we go even smaller, by
factors of one thousand or more, we would eventually
arrive at atoms, the building blocks of matter andnature.
What is of importance here are that the laws thatgovern the pen as a whole and the laws describing theatoms can be different. Classical mechanics governs
our real macroscopic world while “quantum mechanics” is generally thought of as the laws that govern the1atomic world. Throwing the pen at a wall, we allknow it will bounce off, but throwing the atom canproduce a really interesting result. It can tunnel
through it but will never be found in the wall. This is
one of the interesting effects quantum physics allows.
Technical innovation in electronic devices has
become so familiar to us in our daily lives due to theminiaturization trend. Our automobiles we drive
every day now contain many small computers that
control many of its basic functions. The car is probably classical in nature, but it may have had quantum
physics help in designing it. These quantum principles are used for instance in the construction of
the microprocessors that make up the computers.
By embracing these quantum properties, we canbring about a true technological revolution. In short,
it can make possible new things that could not be
achieved in the past (or even thought of), such asbuilding absolute secure networks on a global scaleor next generation computers. Quantum computers(Fig. 1), which are currently attracting significant
worldwide attention, could be billions of times more
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Front-line Researchers

Fig. 1. Schematic of a super-conducting qubit. This is a
key element for the quantum computer.

powerful than the computers we are using today or
could exhibit a level of performance greater than allcomputers in the world combined. Quantum computers could in principle process more data than the total
number of atoms in our Universe!!!
The quantum world is quite unique by the standardsof classical physics. Quantum entanglement suggests, for instance, a phenomenon in which multiple
quanta situated far apart from each other neverthelessare inextricably correlated is possible, much like thetwo sides of a coin. It is hard to believe, but this phenomenon exceeds time and space. The question is,
how do we realize devices that exploit this, and how
do we make quantum principles useful in our everyday lives? The phenomenon of quantum entanglement is turning into an indispensable resource forquantum communications, computing, and metrology. A focus of our group and other researchers in thisfield is to create technology roadmaps extending 20
to 30 years into the future on quantum information
processing (QIP) systems using these quantum principles and to discover how to bring about greatchanges in the world through quantum technology.

will be able to achieve things that we can just not
imagine now. In the field of medical care, it could
become possible to design drugs tailor-made to theindividual patient and their condition, or in the fieldof meteorology, the quantum computer could enableaccurate weather predictions many weeks in advance.
That would have an enormous impact on the harvesting of crops. This is our vision that some may treat asjust a dream, but it will become a reality in the not too
distant future.
In the field of information and communications,data security is becoming a major issue of concern
around the world. To achieve a major breakthrough inthis field, we need to change the rules. Today an
encrypted message is unlikely to be opened unless
one possesses the key for decrypting it or actively
cracks it. However, quantum communications will
make it possible to send messages with absolute security. If the sender and receiver of a message possess arandom bit sequence called a “secret key” that cannot
be predicted by anyone (other than the sender andreceiver), and if that key is destroyed after use, thenconfidential communications can be carried out along
a wireless communications path or a public communications path such as the Internet (Vernam cipher).
The questions is how to get this key. Quantum cryptography is a method of providing the sender andreceiver with such a secret key by having themexchange the quantum mechanical superposition
states between them. This process is called quantum
key distribution (QKD). To give an example, let’s
assume QKD apparatus operating over a distance ofabout 100 km (Fig. 2). The sender and receiver (Aliceand Bob) can obtain a desirable secret key in this way.
Here, Alice sends photons prepared in a few known
states over a fiber to Bob who measures them in arandom basis. When the basis of Alice send photons—Can you tell us something about global research
trends in this field?
The birth of quantum computers and quantum
information enabled devices that will give rise toentirely new industries. For example, e-commerce inthe conventional sense could cease to exist as its security is removed or may need to be completely reegineered. While this may seem a little negative forsociety, there could be some big gains as well. We
Vol. 14 No. 3 Mar. 2016

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Front-line Researchers

Measurement

Alice

Bob

Fig. 2. Principal of QKD.

and Bob measured photon agree, they keep the resulting
bits. Next, they correct for bit errors, and finally, they
shorten the bit sequence to an appropriate length
based on the level of information that can be leaked
to eavesdroppers (nature or Eve).
By the way, I am proud to say that our group is at
the forefront of quantum communications research,especially in QKD and quantum networks. Researchin this area spans a period of nearly 15 years. In the
beginning, communication rates were limited toabout one quantum bit of information per hour. However, we are now proposing schemes for transmitting
millions per second, which was initially doubted by
the research community but is now widely accepted
and admired.
—What made you think of NTT as a place to pursue
your research?
The wonderful research environment! I have experienced research life in universities and companies
overseas, but at NTT, I feel that I am quite fortunate
to be in an environment in which theoretical researchers can interact smoothly with lots of experimentalgroups. Overseas, it is typical to have one experimentalist to ten theorists, but at NTT Basic ResearchLaboratories, the ratio is just the opposite: 10 experimentalist to one theorist (maybe even 20 to 1). WhenI get an unusual idea in my head, I can talk to myexperimental colleagues and say “Is this a crazy idea
or what?” I may quickly be told “It may not be so
crazy. Maybe we should build it!” It is truly a uniqueand wonderful thing to have colleagues like this who
3

can respond quickly to our ideas. The opposite is ofcourse also true, we help them understand many of
their experiments.
Our group is extremely interactive in its approachto research. Whenever a member of our group comesup with an interesting idea, we actively discuss itusing the language of mathematics, and we might
spontaneously start to write equations all over theboard. Of course, these equations could be replacedby conventional words, but it might take about 50
pages of text in either Japanese or English to communicate what these equations are saying in a few
lines.
In these last few years, leading overseas companies
such as HP and IBM have been downsizing theirresearch laboratories, but at NTT, the value of
research and development continues to be appreciated, and basic research is still being given the importance it deserves.
On the other hand, in terms of job duties, rules, anddiscipline, the research laboratories when I entered
NTT were like a typical Japanese company. So I
talked about this with management, telling them that
I wanted to place priority on results, and they allowed
me to pursue my research in an open and transparent
environment with a flexible work system. I believethat a researcher cannot be creative if stuck at a desk
thinking only about what he or she should be doing.
Engaging with your colleagues in a Polo-shirt
and half-pants—it’s results that are important!
—Are you saying that, in the sense of research
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technique and researcher behavior, a flexible
approach is necessary?
Let me give you a typical day in our group as an
example. The members of our group do not lead thelife of a typical business person. I myself get to workby 7:00 a.m. and leave by 4:30 p.m. What is important for a researcher is not to work long hours but tobe productive. I rarely wear a suit at work, and formost of the year I pursue my research activities in apolo-shirt and half-pants. The attitude toward research
has also changed over time. Up to 20 years ago, it wasthought that research was a task carried out by anindividual researcher, but in recent years, this haschanged to research achieved through teamwork.
This can be understood by looking at recent NTT
research papers that generally present the results ofsmall teams of researchers all working in concert.
Everyone in the team has their part to play! In fact,
you are likely to be in several different teams.
When a Japanese researcher wants to get another
opinion from someone, I think it’s common for themto go to a meeting room with that colleague and havea long discussion just between themselves. However,I think a work environment conducive to dynamic andenergetic discussions that can attract and involveother people in the area is essential to stimulating new
ways of thinking.
Whether what you say in such discussions is rightor wrong is not the issue. Making your point clearly
without hesitation makes it possible to fine-tune thetopic being discussed. My group and related laboratories are actually building such relationships. Forme, such an environment and relationship is naturaland matter-of-course. Japanese companies, however,tend to be caught up in vertical relationships, and acommon scenario is to give the right to talk to seniorstaff first and to expect others to follow. In NTT laboratories, as well, there is a hierarchy as reflected byour titles (mine seems to have the word “senior”
attached). However, if we strip this away, we are alljust “researchers,” and who talks depends on the situation. I hope many NTT researchers know that anopen environment exists, and if they come acrosstheir colleagues engaged in a lively discussion, diveright in and join the discussion! (Photo 1)—To maintain flexibility and creativeness in thought,
what do you do in your private life?
When I want to relax, I cook, which is an activity
that gives me much pleasure. In this regard, I’d like toVol. 14 No. 3 Mar. 2016

Photo 1. Promoting active discussions.

mention that, in addition to being a physicist, I am
really a chemist. In the sense of mixing together avariety of materials, cooking and chemistry havemuch in common. Even while I’m cooking, I will
have my computer open with a divided screen so that
I can enjoy, say, a rugby match on one window while
checking out a recipe for a chocolate cake on theother. This enables me to receive two sets of stimuli
at the same time. Actually, ideas come to me quite
frequently in this way. In addition, having my computer always open enables me to write down any
ideas that pop into my head at that time. Of course,
writing down such a random sequence of ideas hardly
results in clear and concise text, but I have fun putting
them all together later, like pieces of a puzzle. Ideas
don’t come easy to me when I’m tired, so I also enjoy
walking and cycling. I walk to and from work every
day, and on weekends, I may walk as far as the Imperial Palace (20 km). I also enjoy my e-book collectionof over 1000 works, and I like reading, in particular,science fiction and manga. I think that the world
described by Arthur C. Clarke in his books has actually become a reality in many respects. The world of
the Japanese manga Dragon Ball Z, on the other
hand, is fantasy, but I enjoy it because it’s different.
4Front-line ResearchersIts unorthodox ideas are “outside the box,” much like
day-to-day research.
Envisioning the future through a dynamic andflexible approach unrestrained by existing
concepts—Dr. Munro, what advice would you give to young
researchers?
All in all, please think outside the box. Your idea
may be crazy, it might seem ridiculous to other people, but out of 100 ideas, one may still be a very goodidea. Pursue themes that can have a great impact onsociety, that can change the world. And in doing so,
don’t be afraid of failure. In fact, failing in solving
problems is not a failure. Use it as an opportunity forthinking how you can do it better in the next step ofyour research. If you can’t fail, you can’t succeed.
Actually, when a young researcher or postdoc comesto my office for consultation, I begin by throwing up
about 100 different ideas in the air. We will sit in frontof a whiteboard and talk nonstop about the feasibilityof a certain idea, what might be attractive about it,
and while it may not be achievable soon, how best to
approach it. Research, in a word, is a passion. Without your own ideas, you are just doing standard workwith little job satisfaction. A researcher has an objec-

5

tive in his or her research, such as “I want to solve
something” or “I want to explore something.” So
without passion, it’s hard to continue and accomplish
something significant. Finally, I would like to emphasize the importance of communication. Actually, thisholds true for all researchers, not just young staff.
Don’t think that you can do it all on your own at yourdesk—please talk to the people around you and ask
questions. Your neighbor may be able to solve a problem that you have been stuck on in just five minutes.
If you sometimes get away from your desk andresearch laboratory, it’s easy to receive stimuli fromthe outside!
—Finally, what are your plans for the future?
It’s very simple: realize these quantum devices!
Actually, quantum mechanics itself is already being
incorporated in high-tech devices. Our challenge is tomake such devices that are actually using quantum
principles even more powerful. This attempt of ours,
however, is not simply an extension of ongoing technology development to make computers or communication devices smaller. Our goal, rather, is to dosomething radically new while using the same principles. In this way, we want to bring about not justchange but a real revolution. To be more specific, weare working jointly with various experimental groups
with the aim of creating a compact quantum device
within the next five to ten years. We are still at thebasic research stage, and talk on how such a device
would actually function is still a bit further away, but
we are steadily advancing.
As for myself, I enjoy my daily work immensely. In
fact, I don’t think of research as “work” but rather assomething that I take extreme pleasure in doing.
What is difficult is separating the pleasure of researchfrom work. We are at the forefront in this field, andour role as researchers is to push the boundaries tofundamentally change society for the good. Research
isn’t evolution, it’s revolution!

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Front-line Researchers

Interviewee profile
William John Munro
Senior Research Scientist, Group Leader,
Theoretical Quantum Physics Research Group,
Optical Science Laboratory, NTT Basic ResearchLaboratories.
He received a BSc in chemistry and physics in
1989, an MSc in physics in 1991, and a DPhil inquantum optics in 1994 from the University ofWaikato, New Zealand. In July 1997 he accepted
an Australian Research Council Fellowship at the
Department of Physics at the University of
Queensland, Australia, to undertake research on
entanglement, methods to characterize it, and its
practical use in QIP. After spending more than
three years in Australia, he joined HP Labs inBristol in November 2000 as a research scientist
to investigate and develop various quantum technologies. After a decade there, he joined NTT
Basic Research Laboratories in 2010 as a research
specialist and was promoted to senior researchscientist in 2014. He was elected as a 2015 OSA
Fellow by the Optical Society of America. He is
also currently a Fellow of both the Institute ofPhysics in the UK and the American PhysicalSociety.

Vol. 14 No. 3 Mar. 2016

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Feature Articles: New Generation Network Platform
and Attractive Network Services

Development towards Building a New
Generation Network Platform andAttractive Network Services
Hiroshi Tohjo, Katsuhiro Shimano, Tatsuya Fujii,
Osamu Akashi, and Hitoshi Masutani
Abstract

At NTT Network Innovation Laboratories, we are working on developing the network and application
technologies for a new generation network and new generation applications. In this article, we briefly
describe some of our development activities including software-defined networking and network functions virtualization, a remote collaboration platform, and a distributed data analysis scheme.
Keywords: SDN, media collaboration, distributed data analysis

1. Introduction
Cloud computing has become a very popular service that makes it easy to access computing resources. It also makes it possible to build new network
services using resources other than cloud computing
resources, for example, using only static network
resources such as mashup web services. Users can
automatically manage cloud computing resources
using application programming interfaces (APIs).
However, networks still require manual operation,
especially telecom carrier networks. Consequently, ittakes a very long time to deploy network resources
and to launch new network services. If the network
infrastructure enabled rapid operation and automation of the network for operators and users, it would
be possible to create attractive network services withcloud computing resources in the same manner as
mashup services. Also, if it becomes possible to flexibly combine computing resources and network
resources, then a new application platform should be
developed for new generation applications.
Software-defined networking (SDN) is a technicalnetworking concept that can provide programmability to network operation via APIs. Network functions
virtualization (NFV) is a network architecture design1

concept in which network functions such as firewalls
and NAT (network address translation) are implemented using network application software and acommodity server that enable the network operator tocreate network services with more than one network
function. In NFV, network services are based on thesoftware used and are managed via an orchestrator.
Thus, SDN and NFV have attractive features, so weare researching SDN/NFV technologies to achieve
network flexibility.
As mentioned previously, SDN/NFV enables theoperator or users to exploit network resources andcloud computing resources. Existing application platforms will have to be reexamined to ensure they canbe used with new generation applications because
most of them were developed based on static network
resources. We are currently developing a remote collaboration platform as a new generation application
to obtain the ultimate communication capabilities.
If a network and applications deployed on it use
many network and cloud computing resources, it will
be difficult to apply the current management technology with them because network management isdesigned based on an assumption of limited network
resources. Consequently, an effective data analysis
technique is necessary in order to rapidly analyze an
NTT Technical Review

Feature Articles

enormous amount of data and a large number of logs
and to determine the appropriate actions. Thus, weare also working on distributed analysis technology.
In this article, we introduce our activities focusedon the development of a new generation network anda new generation application platform.
2. SDN/NFV activities
The software switch is one of the most importantcomponents in SDN because it is utilized as a virtual
switch that allows packet processing between theouter network and an internal virtual machine, andalso between virtual machines. Therefore, software
switches should be capable of high performancepacket processing. We are currently participating in
the O3 project [1] whose goal is to achieve wide area
SDN, and which is funded by the Ministry of Internal
Affairs and Communications of Japan. In this project,
we are developing the SDN software switch Lagopus[2] for high performance packet processing [3].
Lagopus is an OpenFlow software-based switch
application that has already achieved a transmission
speed of 10 Gbit/s and over 1 million flow rules. Furthermore, Lagopus is open source software.
In ETSI ISG*1 NFV standardization, the network
service orchestrator is one of the components of the
NFV architecture. This component largely depends
on the telecom carrier’s operation logic, and therefore, we are currently developing an NFV service
orchestrator called vConductor. vConductor canseamlessly connect multiple network resources tocloud computing resources in order to build various
network services through simple operation.
Lagopus and vConductor are often referred to as
backbone network components. However, in order toaccess various network services from a home orenterprise network, edge network equipment is needed. Customer premises equipment (CPE) is frequently used for connecting a local network, including ahome or enterprise network, to a telecom carrier network. CPE often has only one telecommunication
channel provided by a telecom carrier. However, CPE
that can connect multiple telecommunication channels to achieve flexible network services is desirable
because different types of network service traffic
have different priorities. We are developing Smart
CPE that can support multiple telecommunication
channels for flexible traffic engineering in the manner of SDN/NFV [4].

3. Next generation remotecollaboration platform
Telephone and video communication technology
were originally designed and developed for simple
communication functions. Although these services
provide a remote communication function, it is not
sufficient for rich communication. If SDN/NFV canbe utilized to provide a network infrastructure withsimple and automated operation, we believe that richremote collaboration and communication can also be
realized as a new generation application platform. In
this context, we are developing remote collaboration
technology that includes media time synchronization
technology and highly reliable media packet transmission for audio and video signaling and signalingfor IoT (Internet of Things) [5].
4. Distributed data analysis technique
The network is a very important infrastructure
because it forms the basis of social communities;
hence, it must be stably maintained through proper
network management. However, the amount of data
and logs being produced by the huge amount of network equipment is increasing as more services arebeing added. Furthermore, if SDN/NFV technologies
are applied to the network infrastructure, the telecom
network carrier has to analyze and process such data
and logs to keep their infrastructure stable. Therefore,
we are developing a distributed data analysis scheme
for rapidly analyzing and predicting network failures
or congestion [6].
References
[1]
[2]
[3]

[4]

[5]

Website of O3 project, http://www.o3project.org/en/index.html
Website of Lagopus, http://lagopus.github.io/
N. Sakaida, H. Takahashi, M. Yoshida, and T. Hibi, “SDN Software
Switch Lagopus and NFV Service Orchestrator vConductor for
Developing SDN/NFV,” NTT Technical Review, Vol. 14, No. 3, 2016.
https://www.ntt-review.jp/archive/ntttechnical.php?contents=
ntr201603fa2.html
K. Sebayashi, O. Kamatani, and O. Akashi, “Smart CPE R&D forHighly Intelligent Enterprise Networks,” NTT Technical Review, Vol.
14, No. 3, 2016.
https://www.ntt-review.jp/archive/ntttechnical.php?contents=
ntr201603fa4.html
D. Shirai, Y. Mochida, and T. Fujii, “REMOCOP: Remote Collaboration Platform for a Next Generation Remote Collaboration Support
System,” NTT Technical Review, Vol. 14, No. 3, 2016.
https://www.ntt-review.jp/archive/ntttechnical.php?contents=
ntr201603fa3.html*1 ETSI ISG: European Telecommunications Standards Institute,
Industry Specification Group.

Vol. 14 No. 3 Mar. 20162

Feature Articles[6]

K. Mizutani, T. Inoue, T. Mano, H. Nagata, and O. Akashi, “Distributed Time Series Data Management and Analysis,” NTT Technical
Review, Vol. 14, No. 3, 2016.

Hiroshi Tohjo

Senior Manager, NTT Network Innovation
Laboratories.
He received a B.S. and M.S. in electronics
engineering from Nagaoka University of Technology, Niigata, and a Ph.D. from Osaka University in 1989, 1991, and 1999. He joined NTT
Transmission Systems Laboratories in 1991. He
has been researching object oriented TMN (Telecommunication Management Network) based
operation systems development platform, wide
area ubiquitous network systems and service
systems. He moved to the Visual Communication
Division of NTT Bizlink, where he developed
and managed the visual communication services
and high-quality live-image distribution services
using Next Generation Network (NGN). His current research interests include network architectures, SDN, NFV, content distribution systems,
and collaboration systems and technologies. He
is a senior member of the Institute of Electronics,
Information and Communication Engineers(IEICE).

Katsuhiro Shimano

Senior Research Engineer, Supervisor, Media
Innovation Laboratory, NTT Network Innovation
Laboratories.
He received a B.S. in physics from Waseda
University, Tokyo, in 1991 and an M.S. in physics from the University of Tokyo in 1993. Sincejoining NTT in 1993, he has studied optical networks and network management and relatedareas such as optical network management systems, generalized multiprotocol label switching,
and traffic engineering. He also spent time at theheadquarters working on NGN network architecture from the first phase of construction. Recently, he has been leading the research on SDN andnetwork virtualization at NTT Network Innovation Laboratories.

https://www.ntt-review.jp/archive/ntttechnical.php?contents=
ntr201603fa5.html

Osamu Akashi

Senior Researcher, NTT Network Innovation
Laboratories.
He received an M.S. in information science anda Ph.D. in mathematical and computing sciencesfrom Tokyo Institute of Technology in 1989 and2001. He joined NTT in 1989. His research interests include distributed systems, multi-agent
systems, and network architectures.

Hitoshi Masutani

Senior Research Engineer, Media Innovation
Laboratory, NTT Network Innovation Laboratories.
He received a B.E. in communication engineering in 1999 and an M.E. in electrical, electronic and information engineering from Osaka
University in 2001. After joining NTT Network
Innovation Laboratories in 2001, he studied multicast networking and SIP-based home networking. In 2005, He moved to the Visual Communication Division of NTT Bizlink, where he was
responsible for developing and introducing visual communication services, including an IPbased high-quality large scale video conferencing system and a real-time content delivery system on IPv6 multicast. He also worked on
developing their service order management system and network management system for videoconference services. Recently, he has been developing high performance network function software in telecom carrier network based on NFV at
NTT Network Innovation Laboratories.

Tatsuya Fujii

Group Leader, Media Processing Systems
Research Group, NTT Network Innovation Laboratories.
He received his B.S., M.S., and Ph.D. in electrical engineering from the University of Tokyoin 1986, 1988, and 1991. He joined NTT in 1991.
Throughout much of his career, Dr. Fujii has
been researching parallel image processing andsuper-high-definition image communication networks. In 1996, he was a visiting researcher at
Washington University in St. Louis, USA, where
he directed a digital cinema development project.
He is currently studying advanced applications
based on a real-time video communication system architecture, as well as reliable content distribution systems. He is a member of IEICE, theInstitute of Image Information and Television
Engineers of Japan, and the Institute of Electricaland Electronics Engineers.

3

NTT Technical Review

Feature Articles: New Generation Network Platform
and Attractive Network Services

SDN Software Switch Lagopus and
NFV Service Orchestrator
vConductor for Developing SDN/NFVNorio Sakaida, Hirokazu Takahashi, Masahiro Yoshida,
and Tomoya Hibi
Abstract

In anticipation of the wide deployment of software-defined networking (SDN) and network functions
virtualization (NFV), we at NTT Network Innovation Laboratories have been carrying out research anddevelopment (R&D) of SDN and related network virtualization. This article presents two of the R&D
topics in this field, the software switch Lagopus that corresponds to OpenFlow 1.3, and the NFV service
orchestrator vConductor, which is based on global standard techniques.
Keywords: network virtualization, SDN, NFV

1. Introduction
The implementation of softwarization and the virtualization of network functions are expected toenable flexible and rapid provision of various network services, and therefore, research and development (R&D) and standardization are advancing rapidly in the areas of software-defined networking(SDN) and network functions virtualization (NFV).
Recently, the introduction of SDN technologies indatacenters has progressed a great deal with the
spread of cloud computing and the progress in network virtualization technologies, and the applicationof SDN by telecommunications carriers and in largescale corporate networks is fully underway. Furthermore, the application of NFV to mobile communication core networks is being actively investigated. In
light of this, researchers at NTT Network Innovation
Laboratories are working on developing a network
platform in which new technologies and services canbe rapidly introduced by utilizing software that has
flexibility, and we have therefore quickly taken on the
R&D of SDN and network virtualization.
In this article, we introduce two of our research topics: the high-capacity, high-performance SDN soft1

ware switch Lagopus and the important NFV service
orchestrator vConductor actualized for NFV.
2. Lagopus: SDN software switch
Lagopus is not only intended for datacenters; wealso plan to apply it to wide area networks utilized bytelecommunications carriers, and we have therefore
been actively conducting R&D in order to achieve therequired performance and functionality. Some of thecurrent specifications are listed in Fig. 1.
In terms of performance, Lagopus supports a transmission speed of 10 Gbit/s and over 1 million flow
rules. Since 40-Gbit/s and 100-Gbit/s network interfaces have become less expensive, we are targetingeven higher performance levels in the future.
In terms of functionality, Lagopus supports a wide
range of OpenFlow specifications that include functions targeting wide area networks such as multiprotocol label switching (MPLS) and bandwidth control.
Furthermore, we are expanding the range of applications from not only physical networks but also thefunctions that connect virtual machines and the combined resource allocation administrator that supports
multiple management interfaces. By actualizing all of
NTT Technical Review

Feature Articles

High-performance software switch• 10-Gbit/s wire rate
• 1-M flow entry support
OpenFlow switch specification 1.3.4 support• Ryu certification score: 973/991(http://osrg.github.io/ryu/certification.html)• Multi-table, group table support• MPLS, PBB, QinQ support
Multiple data-plane configuration• High-performance software data plane on Intel x86 bare-metalserver• Intel DPDK, raw socket• Bare-metal switch (in development)
Various management/configuration interfaces• CLI, SNMP, OF-CONFIG (in development), OVSDB (in development)
CLI: command line interface
DPDK: Data Plane Development Kit
MPLS: multiprotocol label switching
OF-CONFIG: OpenFlow ConfigurationOVSDB: Open vSwitch Database Management Protocol
PBB: provider backbone bridge
SNMP: Simple Network Management Protocol

Fig. 1. Lagopus specifications.

these types of performance and functions with software operating on generic x86 architecture servers,
we can reduce equipment costs and achieve rapid
introduction of network services.
In July 2014, we released Lagopus as open source
software (OSS). We provided it as OSS so that it
would be widely applicable and widely used. Various
Lagopus events have been held and hands-on exhibits
sponsored, which have resulted in an active SDN
market. We and other users are continuing to investigate new SDN use cases.
Here, we present two proof-of-concept demonstrations involving the use of Lagopus as application
examples of various SDN use cases.
2.1 SDN-IX
The ShowNet is a network constructed at venue
sites during the annual Interop Tokyo event. It is not
merely an experimental network; it is also a utilization network operated as Internet service providers
and carriers for exhibiting companies and attendees.
At the Interop Tokyo 2015 ShowNet, an SDNbased Internet exchange (SDN-IX) (Fig. 2) was
deployed as a new SDN use case. Its dynamism wasdemonstrated in the Internet exchange (IX)*1 thatconnects networks used at the exhibition sites toexternal networks. The switch that actualizes the
SDN-IX was the Lagopus switch. No failuresoccurred during the event, thus proving stable operaVol. 14 No. 3 Mar. 2016

tion.
Furthermore, through cooperation with the NECOMA (Nippon-European Cyberdefence-Oriented Multilayer Threat Analysis) project, we were able toactualize flexible services through SDN that IXes up
to now could not provide such as protection fromattack traffic and mutual connections between different VLANs (virtual local area networks). The resultsof demonstrating various services and components
were evaluated, and Lagopus received the Interop
Tokyo 2015 Best of Show Award SDI (Software
Defined Infrastructure) Special Prize.
2.2 Segment routing
Segment routing is a network path control methodthat utilizes the advantages of centralized management networks and distributed management networks. It is currently undergoing standardization by
the Internet Engineering Task Force. In segment routing, segment identifications (IDs) are assigned tonodes and links. Route optimization in the network is
autonomously and dispersively performed while
advertising segment IDs using routing protocols suchas the Open Shortest Path First (OSPF) protocol. In
addition, when using MPLS labels, the traffic routecan be autonomously and freely controlled byassociating a segment ID with a specific traffic flow.
*1 IX: Equipment that interconnects Internet service providers.

2Feature Articles

Exterior network

Physical link
Paths between networks

SDN-IX

DDoS attack block

OpenFlowswitchLagopusOtemachi, Tokyo
Makuhari, Chiba
OpenFlowswitchLagopus

Networks inside the event venue
DDoS: distributed denial of service

Fig. 2. Network configuration of SDN-IX for Interop Tokyo 2015 ShowNet.

Customer A

Customer B

Can control pathrouting for eachcustomer

Firewall

Traffic between customer
A and Malware site isblocked by a firewall.

Lagopus

Lagopus

Lagopus

Lagopus

Lagopus

LagopusWebsiteMalwaresite

Fig. 3. Example of segment routing traffic control.

By coordinating our existing OSPF implementation
with Lagopus, we achieved segment routing and presented a demonstration at the Intel Developer Forum2015. In the demonstration, we conducted segmentrouting based traffic control as shown in Fig. 3,
assuming that different network services must be
provided depending on the contract conditions foreach client. More specifically, we implemented control to see if we could pass through the client firewall
based on the contract conditions of each client andshowed that we could limit access to malware sites.
As an actual use case for SDN, we presented an
3

appealing case for simply controlling traffic using
software, which received a high evaluation.
3. vConductor: NFV service orchestrator
vConductor is an NFV service orchestrator prototype developed by NTT Network Innovation Laboratories that connects multiple cloud services andenables construction of network services throughsimple operation.

NTT Technical Review

Feature Articles

Networkadministrator

Network functions are
deployed through GUI.

vConductor
Abstraction layer for network resources(Input)(Input)Objectivefunction

MORSA

Virtual server
control

Network
control

Constraints
CPE
control

Cloud

Datacenter A

Datacenter B
LoadWeb
Firewall Router balancer service Database

End userMORSA: Multi-objective Resource Scheduling Algorithm

Fig. 4. vConductor features.

3.1 End-to-end (E2E) NFV service orchestrator
vConductor operates through a simple GUI (graphical user interface) and can automatically constructvirtualized network functions (firewalls, routers, loadbalancers, etc.), web system functions (web services,
databases, etc.), and applications, as shown in Fig. 4,
by utilizing the infrastructure as a service (IaaS) of
multiple cloud providers. In terms of CPE (customer
premises equipment) for an enterprise user base, thisprototype actualizes E2E NFV service orchestrationthat can create and control virtualized network services that combine multiple networks such as virtualprivate networks (VPNs), the Internet from telecommunications companies, and IaaS from cloud providers [1]. Through assignment of network functions,
vConductor can create network services with a wide
variety of cloud services and can automatically construct redundant virtual networks with backup datacenters. Thus, the user can easily recover the system
by simply switching to the backup system when afailure occurs.
3.2 Architecture that extends global standard
technology
We adopted the NFV specifications developed byVol. 14 No. 3 Mar. 2016

the European Telecommunications Standards Institute Industry Specification Group for NFV (ETSI
ISG NFV), an international standardization body, invConductor as an architecture framework for extending NFV. The relationship between the NFV reference architecture framework prescribed by ETSI ISG
and the vConductor architecture is shown in Fig. 5. In
the ETSI ISG framework on the left, the (1) OSS/BSS(operations support system/business support system),(2) NFV orchestrator, (3) virtualized network function (VNF) manager, (4) virtualized infrastructure
manager, and (5) EM (element management) systemcorrespond respectively to the (1’) user portal, (2’)
service recycle management, various databases,
resource design, SLA (service level agreement)
assurance, (3’) embedded VNF managers, (4’) virtualized infrastructure managers, and (5’) element
managers of vConductor.
In January 2014, ETSI ISG NFV released a technology standard document called Group Specifications that compiled the results of activities carried out
over a period of about two years and included workon use cases, a framework, application management
and orchestration (MANO) functions, and infrastructure construction. In the current Phase 2 activity,
4

Feature Articles

vConductor
NFV Management and Orchestration

Os-Ma

OSS/BSS

(1)

EM 2

EM 3

VNF 1

VNF 2
Vn-Nf

VNF 3

VirtualStorage

Virtual
Network

NFVI
VirtualComputing(2)

Service monitoring(3)
VNF
Manager(s)(2' ) Service recycle management

Nf-Vi

(4)
Virtualised
InfrastructureManager(s)Servicereservation

Resource design

SLA assurance

Other reference points

Resourcescheduler

Performance/ fault
analyzer

Parameter
generator

Parameter
generator

Service order generation
Catalog DB
Service catalog

Element catalog

Instance DB
Service instances

Element instances

Resource DB

Or-Vi

Hardware resources
Storage
Network
HardwareHardwareExecution reference points

Service chain
analyzer

Service, VNF andInfrastructure
Description

Vi-Vnfm

Virtualisation Layer
Vi-Ha
Computing
Hardware

VeVnfmService editor

NFV
Orchestrator

Or-Vnfm(5)EM 1

User portal

(1' )

(5' )
Main NFV reference points

Element managers (plug-ins)
Element
configuration

Physical resources

Logical resources(3' ) Embedded VNF managers (plug-ins)

Element
monitoring

BSS: business support system(4' )Virtualized infrastructure managers
DB: database
Datacenter manager (e.g. OpenStack)
WAN manager (e.g. OpenDayLight)
EM: element management
NFVI: network function virtualization infrastructure
VIM: virtualized infrastructure manager
Nf-Vi: a reference point between NFVI and virtualized infrastructure manager
Or-Vi: a reference point between orchestrator and virtualized infrastructure manager
Os-Ma: a reference point between OSS/BSS and NFV management and orchestration
OSS: operations support system
Ve-Vnfm: a reference point between VNF/EMS and VNF manager
Vi-Vnfm: a reference point between virtualized infrastructure manager and VNF manager
VNF: virtualized network function
WAN: wide area network

Fig. 5. Relationship between NFV reference architecture framework and vConductor system structure.

multiple vendors are developing the MANO functions, and progress is being made on formulating thetechnical specifications for the interface between
each function block. In addition, we are furthering
our investigations into abstraction models and APIs
(application programming interfaces), reliability andquality, and application management related technologies.
We are developing a vConductor prototype whilereferring to the specifications of ETSI ISG NFV,
including the defined interfaces between each function block (e.g., Or-Vnfm, Os-Ma, Or-Vi).
3.3 Multi-purpose scheduling function
In NFV, both physical resources such as hardware
equipment and logical resources on virtual machines
are managed objects, and therefore, resource management inevitably becomes complex. We are developing a multi-purpose optimization method called theMulti-objective Resource Scheduling Algorithm(MORSA) [2] that can assign NFV infrastructure(NFVI) resources while considering multiple con5

straints and stakeholder policies at the same time.
MORSA is a new algorithm that is an improvement
over the genetic algorithm [3] concept, and it has
been adapted for NFVI resource optimization. In
MORSA, two types of limiting conditions, namely
NFVI resource constraints and VNF constraints, areconverted to objective functions. Adjusting theweight balance between each function while performing calculations enables multiple limiting conditions and stakeholder policies to be considered at thesame time, and a diverse Pareto solution set*2 can bederived, as shown in Fig. 6. In this way, the optimal
datacenter can be selected for the VNF arrangement
based on the multiple service requirements (delay,
cost, etc.).

*2 Pareto solution set: The generally obtained solutions when optimizing multiple functions, and a set of solutions showing thetradeoff among functions when changing any of the objectivefunction values. This is also referred to as a Pareto optimal solution.

NTT Technical Review

Feature Articles

Cloud operator,
carrier, etc. demands

Network system demands

Resource constraints: Server capacity: Minimize price: Specified hypervisor: Network capacity: Maximize profit: Maximize reliability: Latency: Power capacity

Constraints

Big data

MORSA

Objectivefunction…

: CPU cores: Minimize DC load…

: Maximize QoS…

: Minimize NW load…

Trade-off

NFV/service
deployment flavor

End user demands

Resource scheduling

CPU: central processing unit
DC: datacenter
NW: network
QoS: quality of service

Datacenter

WAN

Datacenter

WAN

Datacenter

VNF resources are assigned to virtualized infrastructure based on the results of MORSA trade-off analysis.

Fig. 6. MORSA concept.

4. Future development
We are striving to achieve even higher performanceand higher functionality of Lagopus. For vConductor,
we are targeting better operating management technology and application preparation, contributing
toward standardization, and pursuing a wide range offruitful R&D.
To accelerate technological development, we are
not only advancing OSS activities but also further
cooperating widely with partners with expertise invarious fields such as international and domestic vendors and research institutions while promoting theVol. 14 No. 3 Mar. 2016

establishment of collaborative technology.
References
[1]

[2]

[3]

W. Shen, M. Yoshida, T. Kawabata, K. Minato, and W. Imajuku,“vConductor: An NFV Management Solution for Realizing End-toend Virtual Network Services,” Proc. of the 16th Asia-Pacific Network Operations and Management Symposium (APNOMS 2014),
TS2-2, Hsinchu, Taiwan, 2014.
M. Yoshida, W. Shen, T. Kawabata, K. Minato, and W. Imajuku,“MORSA: A Multi-objective Resource Scheduling Algorithm for
NFV Infrastructure,” Proc. of APNOMS 2014, TS4-2, Hsinchu, Taiwan, 2014.
M. Mitchel, “An Introduction to Genetic Algorithms,” The MIT Press,
Cambridge, MA, USA, 1996.

6

Feature Articles

Norio Sakaida

Senior Research Engineer, NTT Network Innovation Laboratories.
He received his B.E. and M.E. from Tohoku
University in 1992 and 1994. He joined NTT
Optical Network Systems Laboratories in 1994
and engaged in research on photonic network
technologies. He was with NTT Communications, where he developed a digital televisiontransmission network and VPN services, from1999 to 2005 and from 2010 to 2014, respectively. From 2005 to 2010, he worked on thedevelopment of a 40G-DWDM (dense wavelength division multiplexing) system and submarine transmission systems at NTT Network Service Systems Laboratories. He joined NTT Network Innovation Laboratories in 2014 and has
been engaged in research on network virtualization technologies such as NFV and SDN. He is amember of the Institute of Electronics, Information and Communication Engineers.

Hirokazu Takahashi

Senior Research Engineer, NTT Network Innovation Laboratories.
He received his B.E. and M.E. in electricalengineering from Nagaoka University of Technology, Niigata, in 2000 and 2002. His current
research focuses on high-performance packet
processing techniques.

7

Masahiro Yoshida

Research Engineer, NTT Network Innovation
Laboratories.
He received a Ph.D. from the University ofTokyo in 2013. He was a research fellow foryoung scientists at the Japan Society for the
Promotion of Science (JSPS) in 2011 and 2013.
His research interests include SDN, NFV, anddatacenter networking.

Tomoya Hibi

Research Engineer, NTT Network Innovation
Laboratories.
He received his B.E. and M.E. in computerscience and engineering from Toyohashi University of Technology, Aichi, in 2010 and 2012. His
current research focuses on high-performancepacket processing techniques.

NTT Technical Review

Feature Articles: New Generation Network Platform
and Attractive Network Services

REMOCOP: Remote Collaboration
Platform for a Next Generation
Remote Collaboration Support
SystemDaisuke Shirai, Yasuhiro Mochida, and Tatsuya Fujii
Abstract

There is increasing demand for work environments that enable collaborative work by people at remotesites. However, existing systems such as video conferencing systems and interactive whiteboards aredesigned for video and teleconferences, and they do not satisfy requirements for capabilities that includewide-ranging actual workflows that use specific devices and applications for work. We propose theRemote Collaboration Open Platform (REMOCOP), an application platform for a real-time remote collaboration environment. REMOCOP provides functions for transmitting and presenting work support
information via audio/video communication.
Keywords: remote collaboration, application platform, computer supported collaborative work

1. Introduction
With business activities being carried out aroundthe globe, the demand for remote collaboration technologies is increasing. As a result, video conferencing systems and web-based teleconferencing systems
designed for information sharing and decision making are widely used. However, these systems are not
optimized for remote collaboration of work processes
such as product design and content creation because
they have not been designed for remote collaboration
systems other than basic video and teleconferencing.
Remote product design requires sharing design applications such as computer-aided design (CAD) software. Remote content creation requires sharing
media assets such as videos and pictures and carryingout real-time previews. These shared applications andmedia assets might also need to be operated or edited
by multiple remote users at the same time. The existing widely used video and teleconferencing systems,
which include interactive remote whiteboards, aresingle-function systems, so it is not possible to create1

the remote collaboration environment described aboveor to implement additional customized functions.
A future collaborative and creative environment forusers in remote locations will need a new frameworkthat enables users to share tools and applications forwork in real-time with audio/video communication,and that also enables transmitting and presenting
work support information (Fig. 1).
2. Proposed application platform
To satisfy the previously mentioned requirements,
NTT Network Innovation Laboratories is proposing
the Remote Collaboration Open Platform (REMOCOP), which has been developed as a core frameworkof a future remote collaboration environment. The
main elements and functions of the remote collaboration environment are expected to be:•	Audio/video transmission for real-time communication between users in remote locations•	Sharing, editing, and operation of working
objects and applications
NTT Technical Review

Feature Articles

Existing
remote collaboration system

Our proposed
remote collaboration system

CAD

Medical images
Sharing/operatingVideo conferencing

Web conferencing
Computing
Officeapplications resources

Interactive whiteboard
Single-function systems designed
only for video/teleconferencing

Applications and resourceson the cloud or in user’s
work environment
Scalable system that increases
efficiency of remote collaborationby sharing applications for work

Fig. 1. Proposed remote collaboration system.

•	Displaying work instructions and augmenting
information to improve work efficiency•	Controlling input devices needed for work suchas a mouse and keyboard, and transmitting their
input data
However, the actual requirements for the remotecollaboration environment depend on the type ofwork and workflow. How much audio/video quality
is needed for sharing working objects or collaborative
work? What kind of input devices and editing functions are needed? In addition, there is a need for network infrastructure control including a way toachieve a dynamic secure connection between various users and locations, as well as cloud resource
provisioning. Thus, having to clarify every required
function for every workflow or to develop a hugemonolithic system that supports all those functions is
not a realistic approach. The creation of a truly practical remote collaboration environment requires anapplication platform as illustrated in Fig. 2, which
can replace, customize, or extend modularized components for remote collaboration so as to optimize thesystem for each workflow.

Augmentation Layer, Media-Time Manager, andCollaboration User Interface (UI). These modules aredescribed in more detail below.

3. Components of REMOCOP

3.1 Augmentation Layer for overlaying work support information
In remote collaboration, a real-time audio andvideo transmission function is necessary for real-timecommunication and for sharing working objects
between users in remote locations. However, therequired media quality and latency depend on theworkflow. Current teleconferencing systems andremote collaboration systems are able to use only theembedded codec on the system; therefore, it is difficult to satisfy such a wide range of requirements. The
Augmentation Layer provides the function that overlays work support information and other additional
information on real-time audio/video. Because it
works separately from the audio/video codec, any
type of audio/video codec can be used regardless ofwhether it is hardware-based or software-based,according to quality requirements. An example inwhich the 4K H.264 codec is used for real-time communication, and the HD (high definition) JPEG
2000*1 codec is used for sharing CAD software as a

A block diagram of REMOCOP is shown in Fig. 3.
REMOCOP is composed of three core modules: an*1 JPEG 2000: An image compression standard and coding systemcreated by the Joint Photographic Experts Group.

Vol. 14 No. 3 Mar. 20162

Feature Articles

Work support information
Input devices

Augmentation data
(Subtitles, etc.)

Working objects

REMOCOP

Environment
capture/ User input

Annotation(Drawing)

Pointer

Overlay

CAD system

Control

Office app

Medicalimaging

Video editor

Media transmission

HEVC
codec

Use

H.264
codec

Video
conferencing
systemJPEG
2000 codec

Network and cloud resources
Network
bandwidth
allocation

Cloud resource
provisioning

Securenetworking

Manage
HEVC: High Efficiency Video Coding

Fig. 2. Components of remote collaboration system.

Collaboration UI
HTML5 userinterface

Teleconference
videoMedia-TimeManagerrighter.

Work support
information

Make it b

Timecode
sharingghter.

ri
Make it b

Augmentation
Layer

Timingcontrolledpresentation

Control/operateresource information

Resources for workon the cloudFig. 3. Block diagram of REMOCOP.

3

NTT Technical Review

Feature Articles

Remotelive video

Working

objectformation

port in
Work supMake itbrighter.

HD JPEG 2000
codec

In

t

vironmenration en

collabotegrated

Make itbrighter.

HTML5 rendering

4K H.264
video

CAD software

Voice recognition Cloud storage
serverComputing forwork support

Fig. 4. Overview and application example of Augmentation Layer.

working object is shown in Fig. 4. The Augmentation
Layer overlays work support information such as
pointers, annotations, instruction text by voice recognition, and PDF (portable document format) files on
the cloud storage. Additionally, the Augmentation
Layer displays work support information with
HTML5*2 rendering, which works in synchronization
with audio/video for communication. Hence, theseparate components shown in Fig. 2 can work as anintegrated remote collaboration system.
3.2 M
 edia-Time Manager for controlling temporal synchronization between multiple types of
media and information
To enable the Augmentation Layer to display work
support information in synchronization with audio/
video, a framework is needed that manages and controls temporal information on all types of media as
well as information for remote collaboration. The
Media-Time Manager extracts timecodes from packets in the audio/video stream for real-time communication. Then it transmits them to the Collaboration UIVol. 14 No. 3 Mar. 2016that manages user input interfaces; in doing so, it
embeds timecodes in user input data packets—for
example, the times of mouse movements—and sends
the timecodes to remote locations. On the receiverside, the Augmentation Layer controls the presentation timing and overlays the data, receiving and referring to the embedded timecodes in the audio/video
packets from the Media-Time Manager. It is also possible to present the data before or after the actualsynchronized timing depending on the characteristics
and requirements of the work support information.
3.3 C
 ollaboration UI to build user interface optimized for each workflow
A function for sharing the pointer and a function fordrawing and annotation are assumed to be common
required functions for remote collaboration. Moreover, many other specific functions are required*2 HTML5: The fifth revision of hypertext markup language(HTML), the standard programming language for creating web
pages.

4

Feature Articles

depending on the workflow such as those enabling
operation with special input devices or those utilizing
cloud storage. Demands for capabilities enablingusers to join the collaboration environment from anywhere using devices such as tablet computers andsmartphones are also increasing. The Collaboration
UI makes it possible to implement these required
functions easily with multi-device and multi-platform
support by enabling us to build user interfaces using
HTML5 and to run required functions on a web
browser. The recent rapid advances in browser functions mean that various input devices including akeyboard, mouse, stylus, and gesture-based interfaces can be utilized by HTML5. Web APIs (application
programming interfaces) also help us leverage external resources such as voice recognition and cloudstorage. Therefore, the Collaboration UI makes thedevelopment of work support functions easy by utilizing various input devices and external resources
with multi-platform support.
4. Application examples
Here, we discuss application examples of remotecollaboration using REMOCOP.
4.1 R
 emote collaborative industrial design with
CAD system
The first example involves remote collaborative
industrial design with a CAD system running on virtualized GPU (graphics processing unit) resources,
where the system is controlled by multiple remoteusers. In this workflow, by sharing the CAD software
screen using a high quality video codec, remote users
can discuss points to be fixed while drawing elementsby hand. A system enabling two remote users to operate the CAD application running on the cloud and tocommunicate smoothly with multiple-channel 60p
live video and multi-channel audio is shown in Fig. 5.
In addition, pictures, movies, and documents needed
for work as reference data can be overlaid. To instructa remotely located person on design using hand drawing, the users only need to draw with a stylus pen anda tablet. To point out specific reference data, the users
only need to use their finger to point at the object
because the gesture interface senses hand movements. These intuitive uses of input devices in accordance with specific intentions dramatically accelerate
the speed of collaboration work. Additionally, theHTML5 based implementation enables users to join
the collaboration work even in a mobile environment
simply by accessing the session URL (uniform
5Fig. 5. A pplication example of remote collaborative
industrial design.

resource locator), although there are limitations inmedia quality or spatial resolution of the work space.
4.2 Remote collaboration in the medical field
Another example is remote collaboration in the
medical field, which requires sharing of medical
images with remote users, searching for similar
images from a database, and operating medical
equipment remotely. In this case, the system has tosupport a display environment for sharing high resolution images. Functions that enable annotation on
images and transmission of data between networked
storage systems are also needed. REMOCOP enables
us to build a very high resolution display environment
using multiple computers and display devices in
sync, and also to easily implement similar image
searches with external resources using web APIs.
Even in an operating room where use of physicalinterfaces such as a mouse and keyboard is prohibited, gesture-based interfaces enable users to control
the system in order to browse or point at shared information.
5. Future prospects
As described in this article, REMOCOP allows us
to create remote collaboration services that satisfy awide variety of user needs. It is also expected that
REMOCOP will be the leading platform for applying
emerging technologies for real working environments such as new interface devices, machine-learning-based human thought process support, and cloud
NTT Technical Review

Feature Articles

functions. To achieve this, the business ecosystem
consisting of users, application developers, device
developers, and service providers should be createdby making the platform open. Finally, we believe that

Daisuke Shirai

Senior Research Engineer, Media Processing
Systems Research Group, NTT Network Innovation Laboratories.
He received his B.E. in electronic engineering,
M.E. in computer science, and Ph.D. in media
design from Keio University, Kanagawa, in 1999,
2001, and 2014. He pioneered the world’s first
4K JPEG 2000 codec system, which enables low
latency 4K60p video transmission on a gigabit
network. He is a veteran in the design and implementation of parallel processing architecture,
hardware codec boards, codec control software,and high-performance forward error correction(FEC) technology. He also developed FireFort, ahigh-performance FEC technology, which is partof the FEC standard in MMT (MPEG Media
Transport). He has applied his expertise acrossmultiple domains through his study of practicalapplications in digital audio and video broadcasting technology, image coding, information theory, networking, human-computer interaction, andsoftware architecture. He is currently researching
the design and implementation of Network Supported Collaborative Work (NSCW), which centers on the unification of high-quality robust
media transmission technologies, multimodal
interaction design, and emerging web-based
technologies.

Vol. 14 No. 3 Mar. 2016

the future remote collaboration environment using
REMOCOP will provide higher work efficiency thana face-to-face environment will.

Yasuhiro Mochida

Researcher, Media Processing Systems
Research Group, NTT Network Innovation Laboratories.
He received a B.E. and M.E. from the University of Tokyo in 2009 and 2011. He is currently
researching remote collaboration elements,
including system architecture, network protocol,interface design, and web technologies. He is amember of the Institute of Electronics, Information and Communication Engineers (IEICE).

Tatsuya Fujii

Group Leader, Media Processing Systems
Research Group, NTT Network Innovation Laboratories.
He received his B.S., M.S., and Ph.D. in electrical engineering from the University of Tokyoin 1986, 1988, and 1991. He joined NTT in 1991.
Throughout much of his career, Dr. Fujii has
been researching parallel image processing andsuper-high-definition image communication networks. In 1996, he was a visiting researcher at
Washington University in St. Louis, USA, where
he directed a digital cinema development project.
He is currently studying advanced applications
based on a real-time video communication system architecture, as well as reliable content distribution systems. He is a member of IEICE, theInstitute of Image Information and Television
Engineers of Japan, and the Institute of Electricaland Electronics Engineers.

6Feature Articles: New Generation Network Platform
and Attractive Network Services

Smart CPE R&D for HighlyIntelligent Enterprise Networks
Katsuhiro Sebayashi, Osamu Kamatani,and Osamu Akashi
Abstract

Enterprise users’ information and communication technology (ICT) demands vary widely from industry to industry and also depend on business conditions and company size. In this article, we present thestatus of our research and development of an enterprise business solution called Highly Intelligent Customer Premises Equipment, or Smart CPE, which can offer smart traffic control and advanced network
management functions for existing wide area network services such as broadband Ethernet and virtualprivate network services. This solution makes it possible to construct optimal customer ICT environments and to meet individual needs.
Keywords: enterprise network, service customization, customer premises equipment

1. Introduction
The information and communication technology(ICT) demands of enterprise users vary widely fromindustry to industry and depend on business conditions and the size of the company. In addition, enterprise users must promptly respond to the changes inthe business environment. Small- and medium-sizedenterprise clients without dedicated network operators have particularly high expectations of carriers
with respect to the construction and operation of their
ICT infrastructure. However, when only existing network services and dedicated, off-the-shelf hardware
virtual private network (VPN) routers are used, it canbe difficult to quickly respond to many different
kinds of requests. Users might request, for example,
a service with a level of quality and price point thatlies between a best-effort service and a guaranteed
quality of service, or they may state that they want torun backup wide area network (WAN) services at all
times. Consequently, a way of quickly and flexibly
customizing services to meet individual customer
needs is required.
NTT Network Innovation Laboratories has been
researching and developing one promising solution
called Highly Intelligent Customer Premises Equip1

ment, or Smart CPE, to meet such requirements.
2. Conceptual overview
A conceptual diagram of Smart CPE is shown in
Fig. 1. Smart CPE serves as a replacement for a VPN
router. Like a conventional VPN router, it simultaneously connects to multiple WAN services. Unlike
existing VPN routers, however, Smart CPE runs carrier services that can be customized according toindividual customer needs.
Smart CPE’s network concierge feature is one way
in which it customizes original services. Ordinary
VPN routers control traffic primarily by switching
between active and backup circuits or simply assigning traffic to a fixed number of circuits. Smart CPE,on the other hand, assesses policies and usage alongwith the state of a client carrier’s WAN services andequipment. Through a combination of optimal traffic
controls and WAN service choices, Smart CPE thenintelligently controls traffic for individual network
flows. To customers, multiple WAN services thus
appear to be a single WAN service that is suited to any
situation.
Smart CPE’s remote maintenance feature represents another way in which it customizes services. By
NTT Technical Review

Feature Articles

Datacenter

Datacenter
Smart
CPE

WAN
serviceA

WAN
serviceB

WAN
serviceC

Seamless

Seen as a single
WAN service by
the customer

Network concierge

Cloud• Replaces VPN routers• Loads the service functionthat a carrier offers• Provides services that varyby company

Smart
CPE
Customerequipment

Assesses usage and needs alongwith the state of a carrier’s networkand equipment to provide optimal
traffic controls, WAN service choices,and other controls that connect withcarrier networks for individual network
flows.

Remote maintenanceWorks together with maintenancedepartments and the operational
systems on a carrier’s network
to quickly diagnose and repair errors
without the need to send an actual
engineer on-site.

Fig. 1. Conceptual diagram of Smart CPE.

working together with a carrier’s operational systems
and maintenance departments, Smart CPE can quickly diagnose and repair errors without the need todispatch an engineer to the site.
Our solution also provides a customer portal forenterprise users, network carriers, and partner companies of our Hikari Collaboration Model, which
involves wholesaling fiber access service, in order tocustomize their services and check on the visualized
service status.
3. Implementation approaches
One approach for implementing the aforementioned concepts is illustrated in Fig. 2. To implement
services that can be quickly and flexibly customized
to meet customers’ needs, we use general-purpose
Linux computers for Smart CPE rather than dedicated hardware because they offer ease of development
as well as remarkable improvements in cost-performance ratios. When we receive a customer request,
we can then customize Smart CPE with application
software implementations of the appropriate services
that would ordinarily be provided by a customer’sservers and networking equipment. We implement
services in application software using the existing
software resources available from the Linux community.
Vol. 14 No. 3 Mar. 2016

Furthermore, we provide customer portals and element management system and network management
system (EMS/NMS) web services for configuring
and controlling Smart CPE services.
4. Architecture
Smart CPE uses a three-layer architecture, as
shown in Fig. 3. The bottom layer has a traffic control
component for packet forwarding and a packet monitoring component for high-resolution traffic measurement. Above this is the platform layer, which provides an abstraction layer for all the functionality
below it. At the top is the application layer, in which
service customization features are implemented. The
platform layer currently provides a northbound application programming interface (API) with traffic control and packet monitoring features for the application layer, but later it will also provide a southbound
API that allows the traffic control component to be
replaced with OpenFlow and bare-metal switches
without changing the platform or application layers.
Both the northbound and southbound APIs will be
REST (representational state transfer)/JSON (JavaScript Object Notation) APIs, which are widely usedby web services, to make it easier to develop applications that provide prompt services and to then connect them to EMS/NMS.
2

Feature Articles

Wide variety of service requests from each customer
Implements services in softwareand then customizes them bychoosing features according tocustomer requests

Networking equipment features

Security
appliances

Network
analyzers

Routers

Load balancers

CustomerportalServices that combine
networking equipment
featuresWeb
services

Fiber-optic
phonesNetworking equipment
control featuresFlowswitches

Firewalls

EMS/NMS

Traffic
shapers
General-purpose Linux PC

PC: personal computer

Fig. 2. Approach for a Smart CPE implementation.

Applications for customizing services
Traffic assignment

Reports by protocol

Specifies which network to
use for any kind of traffic

Visualizes traffic withmillisecond resolution

SLAs by company
Periodically measures
one-way latency andreachability

Server applications
Both open-source
and commercial
software is used.

Northbound API (RESTful, JSON)

Platform (abstraction layer for low-level features)

IP-PBX
NetFlow

Southbound API (RESTful, JSON)

Packetmonitoring
Passive
ActiveTraffic control (routers, firewalls, QoS, and other features)Linux kernel
Current

OpenFlowswitchFutureNetwork switching
Switches networks used byindividual flows according
to measurements

Bare-metalswitchFuture

SNMP Mngr.
IDS
DNS

General-purpose Linux PC
DNS: domain name system
IDS: intrusion detection system
IP-PBX: Internet protocol-based private branch exchange
QoS: quality of service
SLA: service-level agreement
SNMP: Simple Network Management Protocol

Fig. 3. Smart CPE Architecture.

3

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Feature Articles

Cloud
Ordinary conditions: Uses theappropriate network for each packet
flow given current conditions
In case of failure: Prioritizes andbacks up important packet flows

Office A
Smart
CPE

Smart
CPE

WAN service A

Web-based businesssystems

Adjusts bandwidth as well as
the number of network
connections and virtual servers
according to the status of linked
servers and services

Office B

WAN service B

Web-based information systems

Web-based business systems

Web-based information
WAN service C
systems(Backup)Smart
CPE
Opens a connection andresponds to failures
without dispatchingengineers

Fig. 4. Illustrated usage in enterprise networks.

5. Prototype development
We developed a prototype to verify the effectiveness of our Smart CPE concept and architecture, andwe are currently testing it by connecting three offices
via more than two WAN services including the Master’s One Wireless VPN and FLET’S VPN WIDE
(Fig. 4). We are using two types of hardware: desktop
computers and 1U rack servers.
The Linux kernel has the same capabilities as a
VPN router. It supports VLANs (virtual local area
networks), PPoE (point-to-point over Ethernet), GRE(Generic Routing Encapsulation) tunnels, and othervirtual interfaces, and also has NAT (network addresstranslation), firewall, and QoS (quality of service)features. Our prototype’s traffic control component
manages individual traffic flows using the Linux kernel’s standard packet forwarding features to the greatest extent possible. Furthermore, our prototype’s
packet monitoring component uses a 10-Gigabit network monitoring system (PRESTA 10G) [1] developed by NTT Network Innovation Laboratories. This
implements active monitoring of one-way latency
and packet loss between Smart CPE installations aswell as passive monitoring with the same millisecond
resolution as a network analyzer. This functionality is
all available through the northbound API, which weuse in our prototype to implement the following
applications for our network concierge and on-site
maintenance features. Every application can be conVol. 14 No. 3 Mar. 2016

figured and controlled through a customer portal GUI(graphical user interface) (Fig. 3).
• Traffic assignment
This application specifies a WAN service to use
for a per flow basis.
• Network switchingThis application configures upper bounds on thepermissible one-way latency and packet loss rate
for any network flow. When a WAN service metric
exceeds these thresholds, its network flows are
switched over to different circuits. This application
can also save packet dumps for a fixed period oftime around such a switch for use in future troubleshooting.
• SLA (service-level agreement) measurement
This application measures one-way latency andpacket loss rates between Smart CPE installations
for each WAN service. The data appear in visualized graphs on customer portals and can also beexported in a comma-separated values (CSV) format.
• Traffic visualization
This application measures traffic volume for any
network flow—whether configured by protocol,
application (e.g., web, VoIP (voice over Internet
protocol), video streaming), or server—and visually plots them in real time with millisecond resolution on customer portals. This allows network
administrators to notice sudden spikes (bursts) in
network traffic, which lead to packet loss and4

Feature Articles

CustomerportalDesktop
Smart CPE

Fig. 5. Exhibit at NTT R&D Forum 2015.

cannot be discerned through ordinary SNMP
(Simple Network Management Protocol) or NetFlow monitoring. The data can also be exported in
CSV format.
• Network topology maps
This application displays on customer portals amap of Smart CPE connections along with thereal-time traffic volume between Smart CPE
installations for each WAN service. This application also provides Smart CPE uptime monitoring
and can show remote Smart CPE customer portals.
We exhibited this prototype at the NTT R&D
Forum 2015 (Fig. 5). With multiple network flows
using FLET’S VPN WIDE, we demonstrated how we
could switch one particular video flow over to the
Master’s One Wireless VPN in response to variations
in one-way latency. We also demonstrated this samefunctionality at the NTT R&D Messe 2015 using acommercial web conferencing system (MeetingPlaza) and IP-PBX (Internet protocol-based private
branch exchange) (Crossway) installed on our Smart
CPE.
6. Use cases
We plan to continue developing Smart CPE applications that allow enterprise network system integrator engineers at our Hikari Collaboration partnercompanies and in the enterprise sales departments ofbusiness firms to customize WAN services for small5

and medium-sized enterprise users.
We specifically expect to encounter use cases likethe one illustrated in Fig. 6. Under ordinary conditions, our Smart CPE’s network concierge featureuses the appropriate WAN service to access particularservers or for individual application flows given acustomer’s operational policies and conditions. When
there is a network failure or WAN services experience
network congestion, the concierge feature switches
network flows over to WAN services that are functioning properly, prioritizing flows that are mostimportant for the customer’s continued business
operations. We believe that this can contribute to
making our customers’ businesses more efficient.
Furthermore, because Smart CPE’s remote maintenance feature can always check a customer’s network
status, we believe that it can lead to proposals forbandwidth and WAN service adjustments that matchchanges in the customer’s network usage. Throughthe initial connections to customer networks without
dispatching engineers and by speeding up failure
response times, adding and removing virtual servers,
controlling traffic in conjunction with network failures, and integrating with cloud services, we will
strive to provide customized ICT environments to ourcustomers.
As shown in Fig. 6, we are also considering how we
can apply our Smart CPE technology to the movable
ICT units [2] developed by NTT Network Innovation
Laboratories. When a disaster occurs, we could use
NTT Technical Review

Feature Articles

Provides separate
networks to emergency
response organizations

Chooses a suitable network based on theimportance of the information being sent andthe characteristics of the media being used
Main office

ShelterSatellite
Smart
CPE

Organization A

Carrier WAN services

Smart
CPE

Organization B

Organization B

Organization A

Organization A

Smart
CPE

Relief site

Cellular network
Uses the combined
bandwidth acrossavailable network lines

Organization B

Fig. 6. Usage for emergency response.

our Smart CPE for multiple types of WAN connections (e.g., fiber-optic cables, LTE (Long Term Evolution), and satellite) to main offices both inside andoutside the affected areas, as well as for wireless
LAN connections provided by each of the emergency
response organizations both at the disaster site and at
shelters for disaster victims. This would allow the
emergency response organizations to share information using a suitable WAN given its current throughput, the importance of the information being shared,
and the characteristics of the media (e.g., text, audio,
images, or video) being shared. We thus hope to makeSmart CPE capable of sharing information efficiently
when communication resources are limited.

feedback from actual customers, partner companies,
and other businesses; this includes careful investigation of our expected use cases. Ultimately, we believethat we will also need to build application development environments that can be tailored to our partnercompanies and other businesses. In our continued
research and development efforts in which we take
Smart CPE from field trials to a finished product, weplan to exchange ideas related to the development ofservices and scenarios with wider business uses.
References[1]

7. Future development[2]

We have so far developed a prototype with Smart
CPE’s basic functionality. We think that our mostimportant task in bringing Smart CPE to market is tocontinue to develop applications while collecting

Vol. 14 No. 3 Mar. 2016

S. Kuwabara, “Monitoring Technology for Programmable Highly
Functional Networks,” NTT Technical Review, Vol. 10, No. 8, 2012.
https://www.ntt-review.jp/archive/ntttechnical.php?contents=
ntr201208fa5.html
T. Sakano, S. Kotabe, and T. Komukai, “Overview of Movable and
Deployable ICT Resource Unit Architecture,” NTT Technical Review,Vol. 13, No. 5, 2015.
https://www.ntt-review.jp/archive/ntttechnical.php?contents=
ntr201505fa1.html

6Feature Articles

Katsuhiro Sebayashi

Senior Researcher, NTT Network Innovation
Laboratories.
He received a B.E. in electrical engineeringfrom Tokyo Denki University and joined NTT in
1991. His research interests include monitoring
and control of network systems. He is a memberof the Institute of Electronics, Information andCommunication Engineers and the Institute ofElectrical and Electronics Engineers Communication Society.

Osamu Akashi

Senior Researcher, NTT Network Innovation
Laboratories.
He received an M.S. in information science anda Ph.D. in mathematical and computing sciencesfrom Tokyo Institute of Technology in 1989 and2001. He joined NTT in 1989. His research interests include distributed systems, multi-agent
systems, and network architectures.

Osamu Kamatani

Senior Research Engineer, Media Innovation
Laboratory, NTT Network Innovation Laboratories.
He received a B.E., M.E., and Ph.D. in electrical engineering from the University of Tokyo in
1988, 1990, and 1993. He joined NTT Transmission Systems Laboratories in 1993 and worked
on high-speed optical time division multiplexed
transmission systems, optical networking architectures, and high-speed interactive data transfer
applications. He moved to NTT Service Integration Laboratories in 2004 and worked on the
NGN (Next Generation Network) architecture
and transport control protocols and also took partin relevant standardization activities in ITU-T
and ETSI TISPAN. He is currently researchingan internode cross-layer cooperation networkarchitecture that can offer information-valuecentric data processing.

7

NTT Technical Review

Feature Articles: New Generation Network Platform
and Attractive Network Services

Distributed Time Series DataManagement and Analysis
Kimihiro Mizutani, Takeru Inoue, Toru Mano,
Hisashi Nagata, and Osamu Akashi
Abstract

At NTT Network Innovation Laboratories, we are studying sophisticated network management
schemes based on network data analysis. In this article, we focus on a distributed data analysis scheme
for large amounts of network data. With this scheme, the amount of network data transported among
datacenters for analysis can be reduced, which will also reduce costs.
Keywords: distributed database, distributed data analysis, skiplist

1. Introduction
Sensor data and traffic data have recently come tobe stored in datacenters. Analyzing such data makes
it possible to predict traffic jams and network congestion. These data are generated with high frequency,
and the amount becomes increasingly larger as timegoes on. This means that data cannot be managed ina general relational database because a relational
database constructs a rigorous data structure and sacrifices the scalability of data management.
A key-value store (KVS)*1 is a simple data storagearchitecture widely used to manage large amounts ofdata because it stores only simple key-value pairs(Fig. 1). MapReduce*2 is a well-known distributed
data analysis scheme that has good scalability for
analyzing large data sets in parallel, and it is easily
built and deployed on KVS [1]. If all data are distributed fully into KVS, MapReduce quickly achieves
parallel data analysis. The performance of MapReduce can be guaranteed in simple cases of data analysis; however, it is difficult to apply it for complex
analysis such as time series data analysis and distributed machine learning. The specific difficulties are as
follows.
(1)	Currently, the nodes’ states are managed in acentralized server in a general MapReduce platform such as Hadoop [2]. Therefore, the load on
the centralized server may exceed capacity as
1

the number of analysis executions increases.
(2)	The ideal parallel performance of MapReduce isguaranteed in that all data sets are fully distributed in KVS. However, time series data may be
non-uniformly distributed in KVS. For example,
if a large amount of data is concentrated on certain servers, the performance of MapReduceanalysis will be degraded.
(3)	In machine learning analysis using MapReduce,
there is frequent data communication among all
nodes (i.e., the shuffle phase), and this causes
heavy traffic and network congestion.
We have been researching a MapReduce architecture to solve these problems. In this article, we introduce an efficient MapReduce architecture based on
distributed skiplist tree (DST) [3].
2. MapReduce scheme based on DST
DST is a hybrid data structure consisting of both abalanced tree and a linked list such as a skiplist,
which takes only O(log N) operations to search/put/
remove data. To construct a DST in a distributed environment, each node has two values: the location*1 Key-value store (KVS): A database storing pairs of data and theirkey (e.g., <key, data>).
*2 MapReduce: A parallel programming model for analyzing large
data sets.

NTT Technical Review

Feature Articles

Storage server 00

Traffic data of 7:32
0

1

2

9

3

Put into storage
server 8.

8

4

7

5

ID

Region0

9:01–0:00

1

0:01–1:00

2

1:01–2:00

3

2:01–3:00

4

3:01–4:00

5

4:01–5:00

6

5:01–6:00

7

6:01–7:00

8

7:01–8:00

9

8:01–9:00

6

Fig. 1. Data management in KVS.

Routing table
Level Suc Pre
Level: 2(root level)

2
1
0

null
2
1

0

null
8
9

Routing table

Parent: nullChildren: 1, 2, 4, 6, 8
Level: 1

0

2

8
4

6

Level: 0

8

7

1

0

9

6

Location ID

5

Level

Suc Pre

1

4

0

0

3

1

Parent: 0
Children: 32
43

Suc: Closest clockwise node
Pre: Closest counter-clockwise nodeFig. 2. Topology and management of DST.

identification (ID) and the level. The location ID isthe circulated hashed ID, which is used to determine
the ID space region of a node. The level refers to thehierarchy level in the DST, which is determined by
the function of [-logK RAND], where K and RAND
are denoted as the balancing factor and the random
value among [0,1], respectively. Using this function
to determine the hierarchy level, we obtain the probVol. 14 No. 3 Mar. 2016

ability (1/K)l of a node being located at level l. All
nodes in the hierarchy of the node at level 1 must beplaced below level 1, and that node connects all nodes
between the node location ID and its neighbor at level
l. In this way, all of the connections form a DST(Fig. 2). The DST achieves a balanced tree withoutbalancing operations; therefore, the maintenance costof a balanced tree is very low.
2

Feature Articles

0
Level: 2(root level)

Route of location search request
0
Level: 1

2

8
4

6

0

1

2

Level: 0
8
7

3
6

4

5

Node (location ID: 9) joins the DST.

9

Fig. 3. Node join process in DST.

Next, we describe the DST construction procedure
consisting of node join/leave operations. When node
P (location ID p and level l) joins the DST, it requests
an existing node to search its own location in level l.
The node receiving the request checks whether location ID p is between its own ID and its neighbor’s ID
in level l. When the location ID p is not in the ID
region, the receiving node forwards the request to its
own parent node. In contrast, when the location ID p
is in the ID region, the receiving node forwards therequest to the child nodes closest to location ID p. In
repeating the request forwarding, the request arrives
at the node containing p in its own location ID region.
Then, that node divides its own ID region into two ID
regions for itself and for node p, and becomes theneighbor of node P. The summarized procedure for anode to join the DST is that a neighbor search operation using O(log N) request forwarding is carried out(Fig. 3).
When a node leaves the DST, the node does not
inform the other nodes of its leaving. Therefore, thenodes must monitor each other using a heartbeat*3
protocol in order to handle the situation when nodes
leave. The heartbeat protocol involves simple synchronize/acknowledge (SYN/ACK) communications
among nodes. The protocol sends a SYN message toa node and checks whether a corresponding ACK
reply is received. In DST, each node checks child3

node states using the heartbeat protocol. If a parent
node detects that a child node has left, the parent nodesearches for the node neighbor and replaces the leaving node. If the parent node recognizes the neighbornode, the leave is fixed by a few network communications. In the worst case, the parent node must search
for the neighbor node from the entire DST. However,it takes only O(log N) message forwarding by using
the search protocol introduced in the node join procedure. The cost of these node join/leave operations isonly O(log N) message forwarding; therefore, DST
achieves scalable/distributed node management andsolves problem (1) mentioned in section 1.
Next, we introduce the load balancing function in
DST. A root node located at the highest level periodically requests load information (e.g., the number ofreceiving queries per hour) from its child nodes, andthe receiving nodes forward the requests to their childnodes recursively. When the request arrives at thenodes in level 0, the nodes send information about
their own load to the parent node. The parent nodesorts the information in descending order of load andforwards the top and bottom A load information to its
own parent node. Through recursive execution of thisprocess, the root node obtains the top and bottom A*3 Heartbeat: A protocol to confirm the server state (i.e., dead or
alive) through keep-alive messaging.

NTT Technical Review

Feature Articles

3500

Conventional
DST (A = 10)
DST (A = 100)

Standard deviation of the amount of data

3000
2500
2000
1500
1000
500
0

0

1

2

3

4

5

6

7

8

9

10

Number of load information requests

Fig. 4. Number of load information requests vs. standard deviation of the amount of data.

load information from the DST and balances the
popular data among the 2A nodes. This process isrepeated periodically, and the DST is able to balance
the entire load step-by-step, solving problem (2)mentioned in section 1.
Finally, we introduce a traffic reduction scheme
generated by the MapReduce process in the DST. Alldata in the MapReduce process are delivered to theirdestination nodes through the DST. Then, each parent
node combines the delivered data destined for thesame nodes and redelivers them. The efficiency ofthis traffic reduction scheme depends on the characteristics of the time series data, but it is expected toachieve a significant reduction in traffic comparedwith naive delivery and to solve problem (3) mentioned in section 1.
3. Evaluation
We evaluated the performance of DST throughcomputer emulation. In this emulation, there were1000 nodes, and each node had [0, 10,000] timeseries data with a time range of [00:00, 23:59]. For
comparison, we also evaluated the MapReduce platform based on Microsoft Azure [4].
First, we evaluated the effectiveness of load balancing. In the evaluation, we set variable A as 10 or 100
and measured the standard deviation of the amount ofdata among nodes while changing the number of loadVol. 14 No. 3 Mar. 2016

information requests (Fig. 4). We observed from theresults that the effectiveness of load balancing in DST
was higher as A became larger even if the number ofrequests was small.
Next, we evaluated the amount of data transported
in the MapReduce process when the target time range
was changed. The results indicated that DST effectively reduced the amount of transported data as thetarget range was expanded (Fig. 5).
Finally, we evaluated the stability of DST in a churnenvironment, which is where some nodes frequently
join/leave the DST and also replicate data to othernodes more frequently. The frequencies of joining/leaving were set at 0.5, 1, and 2 per second, and eachnode replicates data it holds in one to three of its closest neighbors. In this environment, each node repeatedly sends certain kinds of data to the other node/s at
an interval of 0.2 s. We measured the average successrate of the data transportation (Fig. 6). The results
indicated that the success rate is significantly
improved as the number of replicas increases.
4. Summary and future work
In this article, we introduced the DST and evaluatedits effectiveness through emulation. The next step isto discuss the DST architecture with skiplist experts
and work on making it even more effective. In
addition, we will verify the effectiveness of DST
4

Feature Articles

Amount of transported data

109

Conventional
DST

108

107

106

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time range

Fig. 5. Time range vs. amount of data transported in MapReduce.

Success rate of data transportation (%)

100

2 nodes/s
1 node/s
0.5 nodes/s

80

60

40

20

0

1

2

3

Number of data replicas

Fig. 6. Success rate of data transportation vs. the number of data replicas.

when it is used to analyze real traffic data.
References[1]

5

J. Dean and S. Ghemawat, “MapReduce: Simplified Data Processingon Large Clusters,” Communications of the ACM, Vol. 51, No. 1, pp.

[2]
[3]
[4]

107–113, 2008.
Website of Apache Hadoop, https://hadoop.apache.org
K. Mizutani, T. Mano, O. Akashi, and K. Fukuda, “A Design of Scalable Computing Platform for Continuous Data,” Computer Software,Vol. 30, No. 2, pp. 101–118, 2013.
Website of Microsoft Azure, https://azure.microsoft.com/enus/?b=16.01

NTT Technical Review

Feature Articles

Kimihiro Mizutani

Researcher, NTT Network Innovation Laboratories.
He received an M.S. and Ph.D. from Nara
Institute of Science and Technology in 2010 and2015. His research interests include future network architectures. He received the best student
paper award from the International Conference
on Communication Systems and Applications(ICCSA) in 2010. He also received researchawards from the Information Processing Societyof Japan (IPSJ) and the Institute of Electronics,
Information and Communication Engineers(IEICE) in 2010 and 2013, respectively. He is amember of IEICE and the Institute of Electricaland Electronics Engineers (IEEE) Communications Society.

Takeru Inoue

Senior Researcher, NTT Network Innovation
Laboratories.
He received a B.E., M.E., and Ph.D. from
Kyoto University in 1998, 2000, and 2006. He
was an ERATO researcher at the Japan Scienceand Technology Agency from 2011 through2013. His research interests widely cover thedesign and control of network systems. He
received the best paper award from the AsiaPacific Conference on Communications in 2005
and research awards from the IEICE Information
Network Group in 2002, 2005, and 2012. He is amember of IEEE.

Hisashi Nagata

Researcher, NTT Network Innovation Laboratories.
He received an M.S. in particle physics from
Osaka University in 2013. His recent research
involves network computing and verification
techniques.

Osamu Akashi

Senior Researcher, NTT Network Innovation
Laboratories.
He received an M.S. in information science anda Ph.D. in mathematical and computing sciencesfrom Tokyo Institute of Technology in 1989 and2001. He joined NTT in 1989. His research interests include distributed systems, multi-agent
systems, and network architectures.

Toru Mano

Researcher, NTT Network Innovation Laboratories.
He received a B.E. and M.E in information
science and technology from the University ofTokyo in 2009 and 2011. His research interests
are network architectures and network optimization.

Vol. 14 No. 3 Mar. 20166

Regular Articles

Development of Highly EfficientGroup Modem Module and Turbo
Codec Module for Next Generation
Satellite Communication Systems
Fumihiro Yamashita, Katsuhiko Yamanaka,
and Kiyoshi Kobayashi
Abstract

NTT Access Network Service Systems Laboratories has been developing the key components for a
new satellite communication system named Highly Efficient Satellite Communication System (HESCS),
which will supersede the existing satellite communication systems in the near future.
The key modules we developed in order to achieve HESCS are a highly efficient group modem module(HEGMM) and a highly efficient turbo codec module (HETCM) that can respectively modulate/demodulate and encode/decode a maximum of 64 channel signals. This article introduces the concept of
HESCS and the details of the HEGMM and HETCM.
Keywords: satellite communications, modem, error correction

1. Introduction
The NTT Group has been providing various satellite communication services for the purpose of disaster-relief, as a backup line for a submarine cable forremote island communications, and for maritime
broadband communications (Fig. 1).
Meanwhile, since the rental cost of satellite transponders remains high, the use of a satellite transponder must be as efficient as possible in order to reduce
operating expenses (OPEX). Consequently, NTT
Access Network Service Systems Laboratories is
now developing the key components for a new satellite communication system named Highly Efficient
Satellite Communication System (HESCS), which
improves the spectrum utilization efficiency of satellite transponders. In the near future, HESCS is
expected to supersede the existing satellite communication systems.
HESCS is aimed at solving the problems that the1existing satellite communication systems suffer from.
HESCS is advantageous in that it reduces OPEX byimproving the spectrum efficiency of the satellite
transponder, simplifies network satellite communication facilities by adopting a commonly used network
interface, and provides skill-free monitoring and control functions by adopting an operation system commonly used in the terrestrial network.
This article introduces the concept of HESCS andthe components developed for it, specifically, ahighly efficient group modem module (HEGMM)
and a highly efficient turbo codec module (HETCM)
that can respectively modulate/demodulate andencode/decode a maximum of 64 channel signals.
2. Features of satellite modem (Group Modem)
currently in use
The Group Modem is the satellite modem currently
in use, as shown in Fig. 2 [1]. It consists of the group
NTT Technical Review

Regular Articles

Satellite
Islandcommunications
Maritime
communications

MainlandstationNetworkDisaster-relief
communications

IslandstationNetworkOpS
BasestationInternet

Terminals

Hospital
ESV

BasestationNetwork

Shelter

Disaster area

ESV: earth station on board vessels
OpS: operations system

Fig. 1. Highly Efficient Satellite Communication System (HESCS).

Single-carrier
modem

Group Modem
Multi-channel multi-rate signals

Channelby channel

Single unit

Variable
bit rate

Frequency

Video

Data

Frequency

Voice
Video

Required bandwidth

Data

Voice

Required bandwidth

High-speed communication

Decomposition

Other users
Flexiblearrangement
Frequency

Satellite transponder

Frequency

Channel allocation is impossible.
Spectrumefficiency: low

Composition

Spectrumefficiency: highFig. 2. Features of satellite modem (Group Modem) currently in use.

Vol. 14 No. 3 Mar. 20162

Regular Articles

Multi-rate filter bank (MFB)
Frequency slots are managed in units of powers-of-two.

Carrier 1

Unusable frequency slots

Carrier 3

Carrier 2

Frequency slot

4 slots

8 slots

4 slots

Fig. 3. Problem of unused frequency slots with GMM.

modem module (GMM)*1 and the turbo codec module (TCM)*2. Conventionally, when many channels
are handled in parallel, it is necessary to prepare multiple satellite modems corresponding to the numberof channels. However, one feature of Group Modemis that the distinctive functions of multi-carrier modulation/demodulation in GMM and those of multichannel encode/decode in TCM enable Group
Modem to handle up to 25 channels at various communication speeds simultaneously.
Another major feature is the multi-carrier decomposition/composition of high bit rate signals. An
example of multi-carrier decomposition is also shownin Fig. 2. A single-carrier modem cannot accommodate a broadband signal if the contiguous unused
bandwidth is less than the required bandwidth. However, by decomposing the broadband signal into
multi-carrier signals and arranging them in theunused frequency slots, the broadband signal can be
flexibly accommodated in the limited satellite transponder. This function greatly improves the utilization efficiency of the satellite transponder by reducing the number of unused frequency slots.
3. Technical issues with GMM and TCM
Nevertheless, GMM and TCM do have some technical issues. One such issue with GMM is depicted inFig. 3. GMM adopts a multi-rate filter bank (MFB)
that consists of cascaded two-channel filter banks ina tree-like configuration for multi-carrier signal
decomposition/composition [2]. Each two-channel
filter bank has a high-pass filter and a low-pass filter
followed by a downsampler, and it hierarchically3

divides the input bandwidth. In the MFB, the bandwidth and center frequency of each pass band can bearranged by selecting an appropriate signal in an
appropriate hierarchy. While various bandwidths andcenter frequencies are supported by the MFB, there
are strict rules. Namely, their bandwidth ratio must be
a power-of-two, and their center frequencies are
restricted to certain limited positions. With these constraints, the conventional GMM cannot support arbitrarily assigned FDMA (frequency division multiple
access) signals. This means the number of unusable
frequency slots increases when a required signal
bandwidth and its center frequency mismatches theavailable pass band of the MFB.
In contrast, the existing TCM can handle as manyas 25 channels per unit. However, the functionality of
the next generation disaster-relief satellite communication systems was reconsidered in the aftermath of
the Great East Japan Earthquake that occurred in2011, and it was concluded that the capability of handling up to 50 channels per unit was needed in theevent of a major disaster. For this reason, modifying
the TCM to accommodate 50 channels has become anurgent task.
4. Features of developed HEGMM and HETCM
We propose a multi-rate arbitrary-arrangementtype fast Fourier transform filter bank (MR-FFTFB)*1 GMM: A group modem module that can decompose/compose
multi-carrier signals in the frequency domain and demodulate/modulate multi-channel signals in the time domain.
*2 TCM: A turbo codec module that can encode/decode multi-channel signals.

NTT Technical Review

Regular Articles

FFT
N points

Filter multiplier

Extraction

Zeroinsertion

Variable
IFFT

Overlap& add

M pointsZeroinsertion

Filter multiplier

Variable
IFFT

Overlap& add

M’ points

Fig. 4. Configuration of proposed multi-rate arbitrary-arrangement-type FFT filter bank (MR-FFTFB) in the receiver.

MR-FFTFB
Unconstrained assignment of frequency slots

Arbitrary bandwidth signals at arbitrary frequency slots

Carrier 1

Carrier 2

Carrier 3

3 slots

6 slots

3 slots

Suppression of unused
frequency resources

Fig. 5. Improved spectrum efficiency with HEGMM.

that employs frequency domain signal processing(Fig. 4) [3]. Unlike conventional MFB schemes, the
MR-FFTFB can handle arbitrary bandwidth signals
at arbitrary frequency slots simultaneously. The
operational principle is as follows. The received signals are converted into the frequency domain by Npoint FFT. The FFT points of the desired signal are
extracted, and the number of points is adjusted so thatit becomes the smallest power-of-two by inserting 0.
Then, the extracted FFT points are converted to time
domain signals by variable length IFFT (inverse FFT)
and demodulated.
Since MR-FFTFB can extract the arbitrary bandwidth signal of the arbitrary center frequency, theconstraints on signal bandwidth and its center frequency imposed on the MFB are removed. Thismeans that unlike the conventional GMM, theHEGMM that adopts MR-FFTFB can handle theVol. 14 No. 3 Mar. 2016

arbitrarily assigned, arbitrary bandwidth signals
simultaneously. As a result, HEGMM improves the
spectrum efficiency of the satellite transponder(Fig. 5).
The developed HEGMM provides another functionality that improves usability. Since GMM currently in use cannot demodulate burst signals, anadditional modem for a burst control channel isrequired other than GMM. To solve this problem, we
have newly implemented the functions of modulationand demodulation of burst signals as well as contiguous communication signals. As a result, in HESCS,
the modem for the communication channel and thatfor the control channel are satisfactorily integrated
into a single modem unit.
The configurations of HEGMM and HETCM are
shown in Fig. 6. On the transmitter (Tx) side, theHEGMM modulates Tx data received from the4Regular Articles

Backplane bus
HEGMM
Tx outTx
I/F

Frequency
multiplexer

HETCM
Multichannel
modulation

Memory for time-sharing

Rx in

Rx
I/F

Frequency
demultiplexer

Data

UW
add

Turbo
product

Scrambler

Descrambler

Turboproduct

UW
detection

Coded
data

Communication
channelI/F

Decodeddata User

Multichannel
demodulation

Constellation
monitor

User
I/F

I/F
Controlchannel
I/F

Demodulated
signals

Buffer(a) HEGMM(b) HETCM

I/F: interface
UW: unique word

Fig. 6. Configurations of HEGMM and HETCM.

interface (I/F) board through a backplane bus carrierby-carrier and arranges each carrier at the desired
frequency slots using the frequency multiplexer. On
the receiver (Rx) side, the frequency demultiplexer of
HEGMM decomposes the received muti-carrier signals carrier-by-carrier in the frequency domain anddemodulates each signal carrier-by-carrier. Then the
demodulated signals are passed to the I/F board
through the backplane bus.
In contrast, the signal processing algorithm implemented in HETCM is the same as that implemented
in the TCM currently in use. A single turbo encoder/decoder is repeatedly used in a time sharing manner
among all the channels. Thanks to the adoption of ahigher sampling clock, the number of available channels is increased to up to 64 channels, and the total
available communication speed is also improved to
25 Mbit/s.
Finally, the specifications of the current modules
and newly developed modules are summarized inTable 1. This table indicates that the newly developed
modules greatly improve the performance.
5. Performance evaluation
The fundamental performance of HEGMM andHETCM was experimentally evaluated. An example
of multi-channel multi-carrier signal transmission
using the developed HEGMM and HETCM is shownin Fig. 7. We confirmed that many multi-carrier
multi-rate signals with different modulation schemes
5were transmitted and received simultaneously in one
module, as can be seen in the figure.
In addition, we confirmed that the bit error ratio
performance of the newly developed HEGMM/
HETCM is approximately similar to that of the
GMM/TCM currently in use. The 8PSK (phase shift
keying) and 16QAM (quadrature amplitude modulation), which are newly implemented in HEGMM,
also showed good performance. The use of 8PSK and
16QAM is expected to improve the spectrum efficiency of the satellite transponder further in the
future.
6. Future developments
The HEGMM/HETCM will be implemented in thesatellite communication modem unit (COM-U),
which is now under development. An overall performance evaluation including functional verification ofoperability and connectivity (between COM-Us andbetween COM-U and the satellite terminals currently
in use) will be carried out in 2016.
We are aiming to apply COM-U to future satellite
communication services of the NTT Group for disaster-relief, remote island communications, and broadband maritime communications.
Acknowledgment
This work is supported by the Ministry of Internal
Affairs and Communications of Japan through the
NTT Technical Review

Regular Articles

Table 1. Specifications of GMM/TCM and HEGMM/HETCM.
GMM

HEGMM

No. of carriers

Tx/Rx 256 carriers

Tx/Rx 256 carriersFrequency demultiplexer/multiplexer

MFB

MR-FFTFB
51.2 MHz

Max. bandwidth

25.6 MHz

Max. no. of channels

Tx/Rx 64

Tx/Rx 64

Burst signals

Modulation

Modulation/Demodulation

Modulation

BPSK, π/4QPSK, OQPSK, QPSKBPSK, QPSK, 8PSK, 16QAM

Roll-off ratio

0.2, 0.35, 0.4, 0.5

0.2, 0.35

Turbo block size

TCM

HETCM

(32, 26) × (32, 26)or (64, 57) × (64, 57)(32, 26) × (32, 26)or (64, 57) × (64, 57)

No. of iterations

5 or 101-10Max. bit rate

6.4 Mbit/s

25 Mbit/s

Max. no. of channels

Tx/Rx 25

Tx/Rx 64

BPSK: binary phase shift keying
QPSK: quadrature PSKQAM: quadrature amplitude modulation

10 dB/divLog

Ref −30.00 dBm
BPSK
10 carriers

–40.0
–50.0

16QAM
42 carriers

8PSK
16QAM
8PSK
16QAM
14 carriers 11 carriers 16 carriers 12 carriers

8PSK
4 carriers

16QAM
QPSK
5 carriers 3 carriers

–60.0
–70.0
–80.0
–90.0
–100
–110
–120

Center 125.88 MHz#Res BW 10 kHz#VBW 10 kHz

Span 25.00 MHz
Sweep 953 ms (1001 pts)

Fig. 7. Transmission of multi-channel multi-carrier signals.

Vol. 14 No. 3 Mar. 20166

Regular Articles

funds “Research and Development of Highly
Efficient Frequency Use Technique for the Communication Satellite Transponder” and “Research andDevelopment of Capacity Enhancing Technology for
Satellite Communications by Employing Dynamic
Polarization and Frequency Control.”References[1]

Website of NTT Access Service Systems Laboratories, satellite com-

Fumihiro Yamashita

Senior Research Engineer, Satellite Communication Group, NTT Access Network Service
Systems Laboratories.
He received a B.E., M.E., and Ph.D. in electrical engineering from Kyoto University in 1996,
1998, and 2006. He joined NTT Radio Communication Systems Laboratories in 1998, where heworked on modulation and demodulation
schemes for broadband mobile satellite communications systems. From 2010–2013, he was theAssistant General Manager of the NTT Researchand Development Planning Department. He wastransferred to NTT Access Network Service
Systems Laboratories in 2013. He is currently
working on the development of a new satellite
communication system. He received the Excellent Paper Award of the 14th IEEE (Institute ofElectrical and Electronics Engineers) International Symposium on Personal Indoor Mobile
Radio Communications (PIMRC) in 2003 andthe Young Researcher’s Award from the Instituteof Electronics, Information and Communication
Engineers (IEICE) in 2004. He is a member of
IEICE.

[2][3]

munication technology (in Japanese).
http://www.ansl.ntt.co.jp/history/wireless/wi03.html
K. Tanabe, K. Kobayashi, K. Ohata, and M. Ueba, “Multicarrier/Multirate MODEM Operated by Time-division Multiple Process,”
Proc. of the 20th AIAA International Communication Satellite Systems Conference and Exhibit, AIAA 2002-2069, Montreal, Canada,
2002.
K. Kobayashi, F. Yamashita, J. Abe, and M. Ueba, “A Prototype
Modem for Hyper-multipoint Data Gathering SATCOM Systems—AGroup Modem Applicable to Arbitrarily and Dynamically Assigned
FDMA Signals—,” IEICE Trans. Commun., Vol. E92-B, No. 11, pp.
3318–3325, 2009.

Kiyoshi Kobayashi

Senior Research Engineer, Supervisor andGroup Leader, Satellite Communication Group,
NTT Access Network Service Systems Laboratories.
He received a B.E., M.E., and Ph.D. from
Tokyo University of Science in 1987, 1989, and2004. He joined NTT Radio Communication
Systems Laboratories in 1989. Since then, he has
been researching and developing digital signal
processing algorithms and their implementation
techniques including modulation/demodulationand synchronization control for satellite andpersonal wireless communications systems.
From 2011 to 2014, he was the director of ATR
Wave Engineering Laboratories at Advanced
Telecommunications Research Institute International, where he conducted research on advanced
technologies for wireless communications. He iscurrently working on the development of satellite
communication systems. He is a member ofIEEE and IEICE.

Katsuhiko Yamanaka

Research Engineer, Satellite Communication
Group, NTT Access Network Service Systems
Laboratories.
He joined NTT in 1988 and was transferred to
NTT Access Network Service Systems Laboratories in 2014. He is currently working on thedevelopment of a new satellite communication
system.

7

NTT Technical Review

Global Standardization Activities

Standardization Activities on EMC
for Telecommunication in ITU-T SG5
Naomichi Nakamura, Yuichiro Okugawa,
and Kazuhiro Takaya
Abstract

The NTT Group participates in the development of international standards related to electromagnetic
compatibility for telecommunication equipment as part of its effort to protect its telecommunicationequipment from electromagnetic disturbances and lightning surges and to provide high-quality, highreliability telecommunication services. This article reports on the standardization activities at the ITU-T
SG5 (International Telecommunication Union - Telecommunication Standardization Sector, Study
Group 5) meeting held in October 2015.
Keywords: EMC, ITU-T, standardization

1. Introduction
With a view to maintaining and enhancing the quality and reliability of its telecommunication services,
the NTT Group defines standard specifications onelectromagnetic compatibility (EMC) in the form oftechnical requirements, which must be met for development or procurement of telecommunication systems (Fig. 1). The basic global EMC specifications
are created by the International ElectrotechnicalCommission (IEC) and Comité International Spécial
des Perturbations Radioélectriques (CISPR). The
requirements for telecommunication systems aredeveloped by Study Group 5 (SG5) of the International Telecommunication Union - Telecommunication Standardization Sector (ITU-T) in the form of
ITU-T K series recommendations. NTT technicalrequirements conform to these international standards for the most part, and are instrumental in maintaining the quality and reliability of telecommunication services provided by the NTT Group. This article
introduces the latest standardization activities of
ITU-T SG5.
2. Overview of ITU-T SG5 WP1/WP2Headquartered in Geneva, Switzerland, ITU-T
1

issues ITU-T recommendations, which serve as international standards in the field of telecommunications.
ITU-T consists of 11 Study Groups (SGs). Recommendations on EMC for telecommunication systems
are developed by SG5 (Environment and climatechange). SG5 consists of three Working Parties(WPs). Questions related to overvoltage, earthing(grounding), and safety for telecommunication systems are studied by WP1, and questions related totolerable levels of electromagnetic disturbance emissions, immunity requirements, and human exposure
to electromagnetic fields are studied in WP2.
WP1 and WP2 are addressing the questions indicated in Fig. 2 in the current study period (2013–2016). This article reports on the content of discussions held at the SG5 meeting in Geneva October
12–23, 2015. Draft revisions to existing recommendations and new draft recommendations that were
accepted in this meeting are listed in Table 1.
3. Discussions in WP1WP1 studies how to protect telecommunication
systems from overvoltage generated by lightning, andelectromagnetic interference due to electromagnetic
induction from power systems and electrified railway
systems. The following discussions were held regarding
NTT Technical Review

Global Standardization Activities

EMC 1.1 Standards on EMC for Telecommunication Equipment
5th Edition, July 23, 2015
[Compliance required]Technical Requirements for Electromagnetic Disturbances Emitted from Telecommunication Equipment
TR No. 550004 4th Edition, December 18, 2009
[Compliance recommended]Technical Requirements for Immunity of Communications Equipment
TR No. 549001 3rd Edition, May 11, 2005
[Compliance required]Technical Requirements for Immunity of Telecommunications Equipment to Interference Caused by WirelessDevices in Telecommunication Centers
TR No. 549002 1st Edition, September 18, 2015
[Partial compliance required]Technical Requirements for Resistibility of Telecommunication Equipment to Overvoltage and Overcurrent
TR No. 189001 2nd Edition, June 29, 2012
[Compliance required]Technical Requirements for the Electrical Safety of External Power Supplies for On-premises Information andCommunications Equipment
TR No. 177001 1st Edition, June 29, 2012
[Compliance required]Technical Requirements for Electromagnetic Disturbances Emitted from Lighting Equipment Installed in
Telecommunication Centers
TR No. 174001 2nd Edition, September 18, 2015
TR: Technical Requirement

Fig. 1. NTT Group’s standard and technical requirements related to EMC.

Questions 2 to 5.
Question 2 concerns test methods and requirements
related to protective components and assemblies suchas varistors and surge arresters against overvoltage.
The UK and Germany submitted a contribution thatpointed out the vulnerability of Ethernet ports of PoE(Power over Ethernet)-compatible devices to lightning surges in differential mode, and proposed a test
method in which a 1500-V surge is applied between
pair wires. Whether this test is needed will be discussed in the next and future meetings. A descriptionof the problem of heat being generated when telecommunication cables come into contact with power
cables was added to K.20, K.21, K.45, and K.82 as asupplement.
Question 3 relates to the issues of electromagnetic
induction from power systems and electrified railway
systems, and of the safety of workers in the event ofground faults. The meeting adopted the final draft ofa new draft recommendation, K.hvps2, which defines
the method of measuring ground impedance. The
method takes into consideration a rise in the groundVol. 14 No. 3 Mar. 2016

potential that occurs when a power substation suffersa ground fault. Consent was also given to a new draft
recommendation, K.tup, which defines methods ofprotecting telecommunication devices installed on
utility poles, and to another new draft recommendation, K.jup, which defines the method of protecting
telecommunication cables from short-circuit accidents with power cables in cases where telecommunication cables and power cables share the same poles.
Question 4 addresses requirements for overvoltage
resistibility at interfaces of telecommunication systems, methods of protecting against overvoltage, andelectrical safety. NTT submitted a contribution that
explained the problems with the method of testing
lightning surge at Ethernet ports. It was agreed thatthese problems will be studied in the next and future
meetings as draft revisions to the existing recommendations, K.20, K.21, K.44, and K.45. NTT also proposed a lightning protection method that bridges
power and telecommunication lines. It was decided to
begin studying this method in collaboration with IEC
TC (Technical Committee) 108. The meeting accepted2Global Standardization Activities

ITU-T SG5WP1 (Damage prevention and safety)
Question 2 ( Protective components and assemblies )Question 3 (Interference to telecommunication networks due to power systems and electrified railway systems)
Question 4 (Resistibility and safety in telecommunications)
Question 5 (Lightning protection and earthing of telecommunication systems)
WP2 (Electromagnetic fields: emission, immunity and human exposure)
Question 6 (EMC issues arising from the convergence of ICT and communication equipment)
Question 7 (Human exposure to electromagnetic fields (EMFs) due to radio systems and mobile equipment)
Question 8 (EMC issues in home networks)
Question 9 (Generic and product family EMC recommendations for telecommunication equipment)
Question 10 (Security of telecommunication and information systems concerning the electromagnetic environment)
Question 11 (EMC requirements for the information society)
ICT: information and communication technology

Fig. 2. Questions studied by ITU-T SG5 WP1/WP2.

Table 1. List of recommendations agreed on at the last meeting.
Work item

Recommendation name

K.44 (revision)

Resistibility tests for telecommunication equipment exposed to overvoltages andovercurrents – Basic Recommendation

K.59 (revision)

EMC, resistibility and safety requirements and procedures for connection to
unbundled cables

K.60 (revision)

Emission levels and test methods for wireline telecommunication networks tominimize electromagnetic disturbance of radio services

K.67 (revision)

Expected surges on telecommunications and signalling networks due to lightning

K.hvps2 (new)Method for determining the impedance to earth of earthing systems

K.tup (new)Installation of telecommunication equipment on utility poles

K.jup (new)Joint-use of poles by telecommunication and solidly earthed power lines

K.ldt (new)Lightning protection of the dedicated transformer for radio base station

K.ntt (new)Protection of surrounding structures of telecommunication towers against lightning

K.maps (new)Generation of radiofrequency electromagnetic fields (RF-EMF) level maps

K.bts_emc (new)Electromagnetic compatibility requirements and measurement methods for digitalcellular mobile communication base station equipment

K.secmiti (new)Mitigation methods against electromagnetic security threats

K.ter_emc (new)EMC requirements and test methods for radio telecommunication terminal equipment

the draft revised K.44 version 2, which describes theconfiguration of the circuit that generates a surge
waveform to be applied in an overvoltage test.
3

Question 5 concerns the earthing of telecommunication systems and risk management. The meeting
adopted final drafts proposed by China for several
NTT Technical Review

Global Standardization Activities

new draft recommendations: K.ldt, which concerns
protection of power transformers for wireless basestations against lightning; K.tot, which specifies
earthing and bonding of wireless base stations; andK.ntt, which specifies methods of protecting structures near wireless base stations against lightning.
Brazil proposed a revision to K.67, which specifies
the level and waveform of lightning surges that may
arise in a telecommunication network. The meetinggave consent to it after a discussion was held on thecalculation model for a direct lightning strike on telecommunication lines. In addition, the meeting agreed
to create a new work item in order to develop a newrecommendation, K.psp, which addresses lightning
protection methods in the TT earthing and IT earthing
systems.
4. Discussions in WP2
WP2 is studying emissions from telecommunication systems, immunity to such emissions, and how toprotect the human body against potential harm fromradio waves. The following discussions were held
regarding Questions 6 to 11.
Question 6 concerns EMC problems that arise fromthe shared use of telecommunication networks by different providers, a situation brought about by theliberalization of telecommunications. A discussion
was held on a draft revision to the existing recommendation, K.59, which specifies EMC, voltage
resistibility, and safety requirements and countermeasures for cables. The final draft for this revision was
accepted after the longitudinal conversion loss values
specified in ITU-T Recommendation G.993.2 hadbeen incorporated. The draft revision to the existing
recommendation, K.60 (Emission levels and test
methods for wireline telecommunication networks tominimize electromagnetic disturbance of radio services), received consent after a formula for conversion of tolerable emission levels for a variety ofmeasurement distances was added.
Question 7 deals with human exposure to electromagnetic fields near radio system antennas. The
meeting adopted a new draft recommendation, K.maps,
which describes a method of mapping an electromagnetic field, after a discussion on it from a practical
viewpoint was held. This discussion included issues
such as the selection of colors to be used in electromagnetic distribution maps to indicate different levels of electric field strength. The National Institute ofInformation and Communications Technology and
NTT DOCOMO jointly proposed to add a provision
Vol. 14 No. 3 Mar. 2016that the output measurement of mobile phone basestations be exempt from the application of the existing recommendation, K.52 (Guidance on complying
with limits for human exposure to electromagnetic
fields). It was agreed to study this proposal in the next
and future meetings.
Question 8 covers EMC specifications for telecommunication devices that make up a home network.
Since CISPR is planning to merge CISPR 20 (Soundand television broadcast receivers and associatedequipment immunity standard) and CISPR 24 (Information technology equipment immunity standard)
into the new CISPR 35 (Multimedia equipment
immunity standard), the meeting started the study torevise the existing recommendation closely related tothe above, K.93 (Immunity of home network devices
to electromagnetic disturbances).
Question 9 relates to the study of EMC specifications for new telecommunication services, and tomaintaining the existing recommendations. The
meeting also discussed K.e_faci version 2, a newdraft recommendation being studied at the initiativeof NTT to specify the emission requirements for electronic equipment installed in telecommunication
centers, and K.prox version 1, a new draft recommendation that specifies immunity requirements for radio
systems located adjacent to telecommunication systems. In the discussion on K.e_faci, it was agreed tomake the tolerable emission level of electric equipment equal to the level defined in CISPR 32 in orderto maintain the existing electromagnetic environmentof telecommunication centers. It was agreed to start
the study of K.prox with the assumed radio systems
limited to wireless LANs (local area networks) working in the 2.4/5.2/5.6 GHz band, and then gradually
expand the scope of the frequency band of theassumed radio systems, taking the ongoing study at
IEC 61000-4-39 (Radiated fields in close proximity- immunity test: being studied) into consideration. In
addition, NTT’s proposal to develop a draft recommendation for specifying EMC requirements forlighting devices installed in telecommunication centers was adopted as a new work item under the nameof K.light.
Question 10 focuses on issues pertaining to theelectromagnetic security of telecommunication systems. NTT submitted the final draft for the new draft
recommendation, K.secmiti, which addresses measures to mitigate the effect of electromagnetic wave
attacks. The draft was adopted after a modification
was made to clarify the scope of its application. This
adoption completes the standardization of a series of4

Global Standardization Activities

recommendations related to electromagnetic fieldsecurity, which has been studied at the initiative of
NTT: K.78, K.81, K.84, K.87, and K.secmiti. A draft
recommendation proposed by NTT to prevent cosmic
radiation-caused soft error (phenomenon of malfunctions of LSIs (large-scale integrated circuits) andother semiconductors in electronic systems caused byneutron rays, etc. included in secondary cosmic rays)
was approved. It was agreed to divide the proposed
recommendation into four recommendations: overview (K.soft_ba), test method (K.soft_test), quality
determination method (K.soft_mes), and design
method (K.soft_des).
Question 11 addresses EMC issues related to radio
systems. The meeting discussed the final draft of a
new draft recommendation, K.ter_emc, which specifies EMC requirements for wireless terminals, andconsent was granted after some modifications weremade to the glossary. The next and future meetings
will study a new draft recommendation, K.bwenv,
which specifies the electromagnetic environment for
wearable devices functioning in the 2.4-GHz band.

Naomichi Nakamura

Research Engineer, EMC Technology Group,
Environmental Technology and Management
Project, NTT Network Technology Laboratories.
He received a B.E. in physics from Nihon
University, Tokyo, in 2004 and an M.E. in nanoscience and nanoengineering from Waseda University, Tokyo, in 2006. He joined NTT Energy
and Environment Systems Laboratories in 2006
and studied EMC technology for telecommunication. He is engaged in the research and development of lightning protection and grounding fortelecommunication systems. He is a member of
the Institute of Electronics, Information andCommunication Engineers (IEICE).

5. Conclusion
This article introduced the latest standardization
activities in ITU-T SG5 WP1/WP2. The global penetration of telecommunication systems and mobile
terminals has brought about dramatic changes in theelectromagnetic environment surrounding telecommunication equipment. This has prompted the UnitedStates, European countries, Japan, and also developing countries to actively propose a wide range of newquestions. ITU-T recommendations are international
standards specifying test methods and requirements
tuned to the characteristics of telecommunicationequipment, and they are therefore directly linked to
NTT technical requirements, which are used by the
NTT Group as procurement standards. NTT will
enhance the quality and reliability of telecommunication services by pursuing standardization activities ina way adapted to changes in the environment surrounding telecommunication equipment.

Kazuhiro Takaya

Senior Research Engineer, Supervisor, Environmental Technology and Management Project,
NTT Network Technology Laboratories.
He received a B.E. and M.E. in electrical andelectronic engineering from Okayama University
in 1993 and 1995. He joined NTT Telecommunication Network Laboratory in 1995. He is
researching electromagnetic interference in wireless and wired communication systems anddisaster prevention countermeasures using communication systems. He is currently a groupleader at EMC Technology Group. He is a member of IEICE.

Yuichiro Okugawa

Senior Research Engineer, EMC Technology
Group, Environmental Technology and Management Project, NTT Network Technology Laboratories.
He received a B.E. and M.E. in electrical engineering from Tokyo University of Science in2002 and 2004. He joined NTT Energy and Environment Systems Laboratories in 2004 andstudied EMC technology for telecommunication.
He is currently researching a radiation immunity
test method for vicinity use of wireless devices.
He is a member of IEICE.

5

NTT Technical Review

New NTT Colleagues––We welcome our newcomers to the NTT Group
This is a corner of the NTT Technical Review where we introduce our new affiliate companies.

WizardsgroupIT (information technology) consulting and learning solutions provider; established in 1996; a major
partner with Oracle and Microsoft in the Philippines
Founded in 1996, Wizardsgroup, Inc. has consolidated its strength in high value IT consulting and learning
solutions for Oracle and Microsoft technologies, mainly in the Philippine market. Headquartered in Metro
Manila, the company now employs more than 200 staff in total and also has a satellite office located in the
United States.
In December 2015, NTT DATA Corporation, through its subsidiary NTT DATA Asia Pacific Pte. Ltd., reached
an agreement to obtain 100% of outstanding shares in Wizardsgroup. The transaction is a part of NTT DATA’s
core strategy to accelerate its global business and to widen its global customer base, offering a portfolio andpresence outside of Japan. The collaboration with Wizardsgroup will help NTT DATA drive business in thePhilippines faster and also enables it to leverage the Philippine company’s capabilities in the Asia-Pacific, North
American, and European regions.
For further information about Wizardsgroup, please visit: http://www.wizardsgroup.com/
Contact:
Global Business Sector
NTT DATA Corporation
http://www.nttdata.com/global/en/news-center/pressrelease/2015/122102.html

Taiwan Application Service Management Consulting
IT consulting service provider; established in 2010; a major partner with SAP in Taiwan
Headquartered in Taipei, Taiwan Application Service Management Consulting Co., Ltd. (TASMC) employs
the largest number of SAP professionals in Taiwan and has a solid track record of implementing SAP solutions
for local companies while building stronger cloud solution capabilities, especially for Salesforce.com.

1

NTT Technical Review

New NTT Colleagues

In December 2015, NTT DATA Corporation reached an agreement to obtain 100% of outstanding shares in
TASMC. The transaction is a part of NTT DATA’s core strategy to accelerate its global business and to widen its
global customer base, offering a portfolio and presence outside of Japan. The collaboration with TASMC will
help NTT DATA drive business in Taiwan faster and also enables it to leverage TASMC’s capabilities in China
and the Asia-Pacific region.
For further information about TASMC, please visit: http://www.tasmc.com.tw/?lan=en_US
Contact:
Marketing Department
NTT DATA (CHINA) Co., Ltd.
http://www.nttdata.com/global/en/news-center/pressrelease/2015/122200.html

Vol. 14 No. 3 Mar. 20162

External Awards
IPSJ Kiyasu Special Industrial Achievement Award
Winner: Kenji Takahashi, NTT Innovation Institute, Inc.; Kuniaki
Naoi, NTT Software Innovation Center; Hiroshi Kumeta, Yan Li, andIchiro Nagano, NTT Software Corporation
Date: June 3, 2015
Organization: Information Processing Society of Japan (IPSJ)For the contribution to international standardization and practicaluse of a user identification management technique.
OpenStack Superuser Award
Winner: Toshikazu Ichikawa, Kota Tsuyuzaki, Mitsuhiro Shigematsu, Masahito Muroi, Sampath Priyankara, Takashi Natsume,
Hirofumi Ichihara, Kentaro Tanaka, Tomoko Inoue, Daisuke Morita,
Kazuhiro Miyahara, Tomonori Fujita, Tomoya Mizobuchi, Koji Iida,
Shintaro Mizuno, Kenichi Sato, and Hiroshi Sakai, NTT Software
Innovation Center
Date: October 27, 2015
Organization: OpenStack Foundation
The NTT Group has three OpenStack use cases in production, andits team has contributed 1054 total commits, ranking 18 out of 263
organizations. The OpenStack Foundation launched the Superuser
Awards to recognize, support and celebrate teams of end-users andoperators that use OpenStack to meaningfully improve their businesses while contributing back to the community.
IE Award
Winner: Yukihiro Bandoh, Seishi Takamura, and Atsushi Shimizu,
NTT Media Intelligence Laboratories
Date: December 9, 2015
Organization: Institute of Electronics, Information and Communication Engineers (IEICE) Technical Committee on Image Engineering (IE)
For “A Study of Complexity Reduction for Optimal Design ofRate-constraint Quantizer.”
We formulate the design of an optimal quantizer as an optimization
problem that finds the quantization indices that minimize quantization error. As a solution to the optimization problem, an approachbased on dynamic programming, which is called DP quantization, is
proposed. However, conventional DP quantization does not consider
the design of the rate-constraint quantizer. In this paper, we propose
an optimal design for the rate-constraint quantizer by extending DP
quantization.
Published as: Y. Bandoh, S. Takamura, and A. Shimizu, “A Study ofComplexity Reduction for Optimal Design of Rate-constraint Quantizer,” IEICE Tech. Rep., Vol. 115, No. 350, IE2015-97, pp. 105–110,
Dec. 2015.
Specially Selected Paper
Winner: Hideharu Nakajima, NTT Media Intelligence Laboratories;
Hideyuki Mizuno, Tokyo University of Science, SUWA; and Sumitaka Sakauchi, NTT Service Innovation Laboratory Group
Date: December 15, 2015
Organization: IPSJ Journal Editorial Committee
For “Emphasized Accent Phrase Prediction from Advertisement
Text for Text-to-expressive Speech Synthesis.”
Realizing expressive text-to-speech synthesis requires develop-

1ment of both text processing and the rendering of natural expressive
speech. This paper focuses on the former as a front-end task in the
production of synthetic speech, and investigates a novel method forpredicting emphasized accent phrases from advertisement text information. For this purpose, we examine features that can be accurately
extracted by text processing based on current text-to-speech synthesis
technologies. Among features, the word surface string of the maincontent and function words and the parts of speech of the main function words in an accent phrase are found to have higher potential topredict whether the accent phrase should be emphasized or not
through the calculation of mutual information between emphasislabels and features of Japanese advertisement sentences. Experiments confirmed that emphasized accent phrase prediction using
support vector machine offers an encouraging degree of accuracy forsystems which require emphasized accent phrase locations as context
information to improve speech synthesis quality.
Published as: H. Nakajima, H. Mizuno, and S. Sakauchi, “Emphasized Accent Phrase Prediction from Advertisement Text for Text-toexpressive Speech Synthesis,” IPSJ Journal, Vol. 56, No. 12, pp.
2384–2394, Dec. 2015.
HCG Symposium 2015 Interactive Presentation Award/
Organized Session Award
Winner: Shiro Kumano, Kazuhiro Otsuka, Ryo Ishii, and Junji
Yamato, NTT Communication Science Laboratories
Date: December 17, 2015
Organization: IEICE Human Communication Group (HCG)
For “Automatic Gaze Analysis in Medium-sized Multiparty Conversations Based on Collective First-person Vision.”
Published as: S. Kumano, K. Otsuka, R. Ishii, and J. Yamato, “Automatic Gaze Analysis in Medium-sized Multiparty Conversations
Based on Collective First-person Vision,” HCG Symposium 2015,
Toyama, Japan, Dec. 2015.
HCG Symposium 2015 Interactive Presentation Award
Winner: Ryo Ishii, Shiro Kumano, and Kazuhiro Otsuka, NTT Communication Science Laboratories
Date: December 17, 2015
Organization: IEICE Human Communication Group (HCG)
For “Predicting Next Speaker Using Gaze and Respiration in
Multi-party Meetings.”
Published as: R. Ishii, S. Kumano, and K. Otsuka, “Predicting Next
Speaker Using Gaze and Respiration in Multi-party Meetings,” HCG
Symposium 2015, Toyama, Japan, Dec. 2015.
ASRU 2015 Best Paper Award Honorable Mention
Winner: Takuya Yoshioka, Nobutaka Ito, Marc Delcroix, Atsunori
Ogawa, Keisuke Kinoshita, Masakiyo Fujimoto, NTT Communication Science Laboratories; Chengzhu Yu, The University of Texas at
Dallas; Wojciech J. Fabian, Miquel Espi, Takuya Higuchi, Shoko
Araki, Tomohiro Nakatani, NTT Communication Science Laboratories
Date: December 17, 2015
Organization: ASRU 2015 (The 2015 IEEE Automatic Speech Recognition and Understanding Workshop) Committee
For “The NTT CHiME-3 System: Advances in Speech Enhancement and Recognition for Mobile Multi-microphone Devices.”

NTT Technical Review

Papers Published in Technical Journals and Conference Proceedings

Published as: T. Yoshioka, N. Ito, M. Delcroix, A. Ogawa, K.
Kinoshita, M. Fujimoto, C. Yu, W. J. Fabian, M. Espi, T. Higuchi, S.
Araki, and T. Nakatani, “The NTT CHiME-3 System: Advances in
Speech Enhancement and Recognition for Mobile Multi-microphone
Devices,” Proc. of ASRU 2015, pp, 436–443, Scottsdale, Arizona,
USA, Dec. 2015.
IEICE Electronics Society LQE Young Researchers Award
Winner: Ryo Nakao, NTT Device Technology Laboratories
Date: December 18, 2015
Organization: IEICE Technical Committee on Lasers and Quantum
Electronics (LQE)
For “High-speed Operation of GaAs/InGaAs Metamorphic Lasers

Emitting at 1.3 μm.”
We demonstrate a lattice relaxation control by in situ curvature
measurement for a metamorphic buffer. Using this relaxation control,
we investigated a thin (240 nm) In0.15Ga0.85As metamorphic buffer
for fabricating an un-strained In0.10Ga0.90As quasi-substrate on a
GaAs substrate and succeeded in fabricating a 1.3-µm metamorphic
InGaAs multiple-quantum well laser diode (LD) on the metamorphic
buffer. We confirmed that the LD was directly modulated at 25 Gbit/swith a high-characteristic temperature (T0 = 187 K).
Published as: R. Nakao, M. Arai, W. Kobayashi, T. Yamamoto, and
S. Matsuo, “1.3-µm InGaAs MQW Metamorphic Laser Diode Fabricated with Lattice Relaxation Control Based on In Situ Curvature
Measurement,” IEEE J. Sel. Top. Quantum Electron., Vol. 21, No. 6,
p. 1501407, Nov. 2015.

Papers Published in Technical Journals andConference Proceedings
Adaptive Pre-equalization Using Bidirectional Pilot
Sequences to Estimate and Feed Back Amplitude Transfer
Function and Chromatic Dispersion
S. Okamoto, M. Yoshida, K. Yonenaga, and T. Kataoka
Proc. of the Optical Fiber Communication Conference and Exhibition (OFC) 2015, Th2A.29, Los Angeles, CA, USA, March 2015.
We propose an adaptive pre-equalization system that compensates
the amplitude transfer function and chromatic dispersion using estimates transmitted from the receiver. Two kinds of pilot sequences areused for estimation and mutual communication.

5 x 1-Tb/s PDM-16QAM Transmission over 1,920 km Using
High-speed InP MUX-DAC Integrated Module
A. Sano, M. Nagatani, H. Nosaka, and Y. Miyamoto
Proc. of OFC 2015, M3G.3, Los Angeles, CA, USA, March 2015.
We demonstrate wavelength division multiplexed transmission of
75-Gbaud PDM (polarization-division multiplexed)-16QAM(quadrature amplitude modulation) signals over 1,920 km. An InPbased high-speed and compact MUX-DAC (multiplexer-digital-toanalog converter) integrated module with bandwidth exceeding 40
GHz enables the long haul transport of 1-Tb/s superchannels composed of just two subcarriers.

Dense SDM (12-core × 3-mode) Transmission over 527 km
with 33.2-ns Mode-dispersion Employing Low-complexity
Parallel MIMO Frequency-domain Equalization
K. Shibahara, T. Mizuno, H. Takara, A. Sano, H. Kawakami, D.
Lee, Y. Miyamoto, T. Ono, M. Oguma, Y. Abe, T. Kobayashi, T.

Vol. 14 No. 3 Mar. 2016

Matsui, R. Fukumoto, Y. Amma, T. Hosokawa, S. Matsuo, K. Saito,
H. Nasu, and T. Morioka
Proc. of OFC 2015, Th5C.3, Los Angeles, CA, USA, March 2015.
We demonstrate 12-core × 3-mode dense SDM (space divisionmultiplexing) transmission over 527-km graded-index multi-core
few-mode fiber without mode-dispersion management. Employing a
low baud rate multicarrier signal and frequency-domain equalization
enables 33.2-ns differential mode delay compensation with low computational complexity.

120.7-Tb/s MCF-ROPA Unrepeatered Transmission of
PDM-32QAM Channels over 204 km
H. Takara, T. Mizuno, H. Kawakami, Y. Miyamoto, H. Masuda, K.
Kitamura, H. Ono, S. Asakawa, Y. Amma, K. Hirakawa, S. Matsuo,
K. Tsujikawa, and M. Yamada
Journal of Lightwave Technology, Vol. 33, No. 7, pp. 1473–1478,
April 2015.
We demonstrate the unrepeatered transmission of over 100 Tb/s byemploying a multicore-fiber-based remote optically pumped amplifier. We establish 120.7-Tb/s, 204-km seven-core fiber transmission
with the aggregate spectral efficiency (SE) of 53.6 b/s/Hz, a record
capacity per fiber and the highest SE for unrepeatered transmission.
We also realized the highest capacity per core of 17.2 Tb/s (180 ×
95.8 Gb/s) and SE of 7.6 b/s/Hz by using the polarization-divisionmultiplexed 32-quadrature amplitude modulation format for unrepeatered transmission.

2

Papers Published in Technical Journals and Conference Proceedings

Filtering-tolerant Transmission by the Walsh-Hadamard
Transform for Super-channel beyond 100 Gb/s
K. Shibahara, A. Masuda, H. Kishikawa, S. Kawai, and M. Fukutoku
Optics Express, Vol. 23, No. 10, pp. 13245–13254, May 2015.
Super-channel transmission is a promising solution to increase thecapacity of a channel beyond 100 Gb/s in next-generation optical
networks. The performance of a super-channel comprising multiple
subcarriers, however, degrades if optical filtering distortions occur inparticular subcarriers. In this paper, we propose a method that
improves super-channel performance by dispersing the distortions
over all subcarriers. We also numerically demonstrate that the method effectively mitigates the filtering induced penalty suffered bysuper-channels.

Optical 8-dimensional Time-polarization Modulation Using
Square-QAM-constellation and a Simple Decoding Algorithm
M. Nakamura, M. Yoshida, F. Hamaoka, and K. Yonenaga
Proc. of the 20th Opto-Electronics and Communications Conference (OECC 2015), JThA.93, Shanghai, China, June/July 2015.
We propose optical 8D time-polarization modulation using squareQAM-constellation and a simple decoding algorithm. Experiments
show that the proposed modulation format can achieve significant
gain and that the decoding algorithm has the same performance as
conventional maximum-likelihood-detection.

High-capacity Multicore Fiber Transmission Technology
H. Takara, T. Mizuno, A. Sano, and Y. Miyamoto
Proc. of OECC 2015, JThA.11, Shanghai, China, June/July 2015.
This paper reviews recent work on and issues with high-capacity
multicore fiber transmission for terrestrial systems. Unrepeateredtransmission of over 100 Tb/s by employing an MCF-ROPA (multicore-fiber-based remote optically-pumped amplifier) is also
described.

Multi-stage Successive Interference Cancellation forSpectrally-efficient Super-Nyquist Transmission
K. Shibahara, A. Masuda, S. Kawai, and M. Fukutoku
Proc. of ECOC 2015 (the 41st European Conference on OpticalCommunications), Valentia, Spain, September/October 2015.
The use of multi-stage successive interference cancellation(M-SIC) for super-Nyquist transmission is proposed. Simulation andtransmission experiment results showed carrier spacing was reduced
by 20% for QPSK (quadrature phase-shift keying) signals. Signal
performance was enhanced when M-SIC was used with non-uniform

3

power transmission.

Impact of Management Data Placement in NFV Service
Coordinated across Multiple Datacenters and WANs
A. Taniguchi, T. Yamazaki, Y. Yoshida, T. Kawabata, N. Sakaida,
and T. Shimizu
Proc. of CNSM (the 11th International Conference on Network
and Service Management), Barcelona, Spain, November 2015.
As network functions virtualization (NFV) technologies haveemerged, some standardization bodies such as the European Telecommunications Standards Institute have advanced standardization
activities on their functional blocks and interfaces. However, several
issues such as where virtual network configuration information
should be placed or how a virtual network configuration among Virtualized Infrastructure Managers (VIMs) should be handled have notbeen standardized yet. This paper proposes several candidates toaddress these issues, and discusses their advantages and disadvantages from various viewpoints such as security.

The Behavior Generation Modeling Method to Extract theReason to Select Shops
N. Takaya, K. Esaki, K. Ishiguro, and Y. Ichikawa
IPSJ Journal, Vol. 57, No. 1, pp. 145–156, January 2016 (in Japanese).
We propose SHOP-LDA, which captures latent patterns of user
product adoption behaviors. The proposed model is a probabilistic
generative model that extracts “topics,” explaining why users selectshops and items. Experimental results with real-world e-commerceuser log data show that the proposed model is able to estimate user
segments that are interpretable and possibly are beneficial for business practices. Furthermore, this method is applicable to emerging
services that use several shop orchestration services such as ID cooperation and point alliance.

Commuting Quantum Circuits with Few Outputs are
Unlikely to be Classically Simulatable
Y. Takahashi, S. Tani, T. Yamazaki, and K. Tanaka
Quantum Information and Computation, Vol. 16, No. 3&4, pp.
251–270, March 2016.
We show that there exists a commuting quantum circuit that is notclassically simulatable unless the polynomial hierarchy collapses tothe third level. This is the first formal evidence that a commuting
quantum circuit is not classically simulatable even when the numberof output qubits is exponentially smaller than that of input qubits.

NTT Technical Review