R&D Spirits
IP Network Technologies for the Ubiquitous Era
Kouichi Seino
Project ManagerEmerging Communication Architecture Project
NTT Network Service Systems Laboratories

The Emerging Communication Architecture Project of NTT Network Service Systems Laboratories has been promoting research in IP network platform technologies with a view toward
the ubiquitous era for the past several years. Now that IPv6 is about to become a standard protocol, we spoke to Project Manager Kouichi Seino about the types of services that will become
available and where this field is heading in the near future.

Pursuing three platform technologies
supporting networks in the IPv6 era
Editor: Please tell us the theme of your current
research and give us a brief overview.
Seino: Our project focuses on three main themes: “IPNomadic,” “Peer-to-Peer (P2P),” and a software platform known as “Softswitches.” Let me explain eachof them briefly. IP Nomadic is an IP service that provides seamless and secure personal communication
environments from a wide range of locations. We are
currently researching network platforms for theseservices, including mobile IP technologies, seamless
access management technologies, and nomadic presence technologies, and we are also developing systems based on these technologies (Fig. 1).
P2P is a new style of using the Internet that sharesinformation and knowledge in real time between terminals and devices participating on the Internet,
enabling collaboration in a given task by several“peers.” Conventional telephones have a centralized
system in which switching equipment relays calls,
but the premise of P2P is that an “equal and smooth
relationship” is formed among devices. We are working on developing the mechanisms for these relationships (Fig. 2).
Softswitches are network controllers that achieve avariety of IP services. They control media gateways
4and terminate different types of communication protocols, thus enabling call control, session control, andthe control of various types of network functions. Wehave also incorporated standardized technologies andwill provide application programming interfaces(APIs) such as Parlay and JAIN. We are also participating in activities concerning the standardization ofthese interfaces (Fig. 3).
E: What are the main technological points to thisresearch?
S: Each of these three themes involves unique technologies. For the mobile IP technologies in IP
Nomadic, we have been conducting research on thepractical application of mobile IPv6 agents on a scaleof up to 100,000 users in preparation for standardization. Route optimization technology for carrier networks is another area where NTT is offering proposals on a global scale. In terms of seamless accessmanagement technologies, we are developing
authentication technologies that will enable the user
to freely select access methods. In nomadic presencetechnologies, we are developing functions that havenever been available before, for example, functions
for obtaining and managing positional information
and regional information from network devices, aswell as terminal information acquisition and management functions.
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Intranet

On the move

Mobile office

Mobile IPTunneling

Mobile VPN

Content server
ISP
Content server

IP nomadic service network
Presenceserver

HomeMobile IPMobile IPlMulti-accessauthentication
database
AAA

Mobile IP
3G mobile network

ISP roaming

High-speed broadband access networks(wireless LAN, FTTH)(IP/ATM)

AirportInteractive communications

WirelessLAN

Hotspot

Mobile services

Content distribution
Inter-media handoverSeamless access
VPN: Virtual Private Network
AAA: Authentication, Authorization, and Accounting
ISP: Internet Service Provider

Fig. 1. Outline of IP Nomadic service.

Client-server modelP2P models

Content server

Discovery function
Discovery operation
ContentDelivery

ClientPure P2PPeers have an equal role in both
discovery and delivery.

Hybrid P2PPeers have an equal role only indelivery.

Fig. 2. Characteristics of P2P technologies.

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Applications distributed ascommercial products
Market Market Market
APL
APL
APL
Market Market Market
APL
APL
APL

Connections using
international standard
protocols

APL
APLServiceprovider
Service provision
other than carriers

Installation inmarket applications

Service Agent/application serverIntegrated OSS(operation)
JAIN, Parlay,SIP, etc.

SNMP/CORBA

MarketMarket
APL
APL･ APL-oriented management･ CA facility management
ISUP

SIP (SIP-T)

Existing networks
H323,
SIP

H.248
IP networks

Other Call AgentMedia gateway
H.323/SIP terminals
APL: Application
OSS: Operation Support System
CA: Call Agent

Fig. 3. Overview of Softswitch.

In P2P, we are working to resolve problems currently being faced, such as the large amount and concentration of management, by distributing content
management, storage, and processing capacity
among peers.
In Softswitches, we are working on technologies
for separating transport networks from service control functions to achieve greater economy and independent development of networks. At the same time,
we are promoting the development of related technologies to enable signal processing and greater reliability through software, as well as call control protocol processing in conformance with IP networks.

From visions to reality: toward ResonantCommunication
E: Where will these new technologies be used?
S: Stated very simply, these technologies will be used
to achieve “Resonant Communication,” which isNTT’s vision for the ubiquitous era. For example, theapplication of mobile IP in public networks will
enable continuous communication across a variety ofnetworks. Seamless access management technologies
will be used in authentication to accommodate multiple accesses, and nomadic presence will be used for6

real-time location management while the user is on
the move, thus enabling services to be provided in avariety of locations in keeping with the user’s requirements.
The field where P2P has been attracting attention
recently is Grid computing. Here, massive computations, such as the analysis of genetic information, aredistributed among PCs throughout the world toenable performance exceeding even that of supercomputers. P2P is used for a series of mechanisms inwhich the circumstances of individual PCs (peers) arematched in real time and programs are loaded onto
available PCs.
The most common area where Softswitches areused is in VoIP (voice over Internet protocol), butthey will have a wide range of other applications askeys for interactive multimedia communications.
There are still a number of issues related to the development of VoIP services, but we are moving ahead
with our technical investigations to cope with them.
E: What form do you think these technologies willtake in the next three to five years?
S: We expect that the specifications for mobile IPv6
will probably be fixed by the end of this year. Whenthat happens, all vendors will most likely begin develNTT Technical Review

R&D Spirits

oping commercial products. For the time being, IPv4
and IPv6 may well be mixed together. In a few years,mobile IP will become an integral part of public, corporate, and household networks. Mobile routers will
be installed in trains and automobiles, opening theway to applications in ITS (Intelligent Transport Systems) as well. Then, as home information appliances
become more popular, PDAs and other personal
mobile terminals will handle all mobile control as akind of mobile router, eventually evolving into “personal area networks.”
Recently, illegal copying has been a major black
mark against P2P, but copyright management andother security technologies are expected to become
available for general use very soon. In the future, wewill see the formation of network communities thatcooperate, combine, and divide, reflecting each member’s sense of values; in these communities, individual terminals will play a leading role. That is, thesecommunities will form spontaneously and multiply.
Regarding Softswitches, it’s hard to imagine any
major changes in architecture. Platform-independent
trends will continue to strengthen as an extension ofcurrent developments. However, I think some variations will arise with the proliferation of VoIP and SIP(Session Initiation Protocol). That is to say, we willsee demands for greater reliability as these networks
become social lifelines, trends toward cost reduction
when switches become specialized for use in SIP signaling, and the enrichment of added service functions
like class 5 switching. Another possibility is thatthese elements will all be integrated into a new formof service.
E: What are the directions for research in the future?
S: We will strive to achieve more advanced ubiquitous environments. For example, right now, mobile
communications takes place only on the level of individual terminals, but in the future, we may see cases
in which entire community networks move. Taking
this type of development into account, mobile IP
technologies will have to evolve even further. Specifically, we are planning to promote research anddevelopment in layered mobile IP technologies inwhich mobile management is carried out on global
and local layers, and in applications targeting publicaccess to ad hoc networks. We will move ahead withresearch focusing on the development of IP Nomadic
for personal area networks in combination with home
information appliances, to achieve more personal,
highly convenient communication services, and will
Vol. 1 No. 4 July 2003

also consider incorporating sensor network technologies with IP Nomadic technologies. In any case, wewill carry out our research and development activities
based on NTT’s vision as a carrier with close attention to user needs.

Leading the world with original technologies
and making major contributions tostandardization
E: Tell us about the international and domestic trends
in this research.
S: Regarding IP Nomadic, Hotspot™ services
appeared on the scene a few years ago, using highspeed wireless LANs. And as you may know, NTTcurrently leads the world in the field of third-generation mobile phones. The next stage will probably
focus on the development of services using mobilemanagement on the IP level, but since mobile IPv6
has not yet been completely standardized, commercial products have not appeared in full force. We are
the first in the world to begin research and development in this area.
In P2P, the highest profile activities are being
undertaken by Sun Microsystems, which is distributing its JXTA architecture free of charge, andMicrosoft, which is advocating P2P networking on its.NET™. We at NTT have also developed a P2P platform called SIONet, which offers links to digitalrights management. The key to P2P is letting the user
easily obtain the desired information from among thehuge volume available, so research on efficient searchalgorithms is advocated. We are promoting efficient
searching technologies using “distributed hash tables(DHTs*1),” such as CAN, Chord, and Freenet, and ofcourse we are working on our own evaluations andfurther studies as well.
Regarding trends in Softswitches, SIP has shown
great potential for some time now, and its use has
spread rapidly since Microsoft adopted it in Messenger. Aside from Microsoft, venture companies havebeen very active in the field of SIP servers. Nevertheless, core VoIP systems are gradually being narrowed
down, mainly to the major switching device vendors.
E: What types of activities are being undertaken byinternational agencies and commissions?
*1 The locations of the values are registered in places (PCs or peers)determined by a hash function, and the values can be referenced
rapidly.

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S: NTT announced the IP Nomadic concept atWTC/ISS2002 as the main technology for making
this a reality. We have also proposed mobile IP route
optimization technologies to the IETF (Internet Engineering Task Force) as an Internet draft, and in bothcases we have received excellent responses. We feelthat disseminating information about the development of terminals and supporting mobile IP technologies will be essential to promote the proliferationof IP Nomadic services. Establishing a global mobile
IP roaming environment will also be indispensable.
We are thus promoting individual collaboration withinfluential terminal software vendors and undertaking activities with various industries in an openforum. The Certification Working Group—an assembly geared toward the advancement and proliferationof IPv6—is a perfect example; in this Group, as theleader of the mobile IP-SWG, NTT has been a drivingforce behind the creation of standard installation
specifications and other activities. Regarding P2P,
NTT is also a member of the Global Grid Forum(GGF), into which the former P2P Working Groupwas merged. As for Softswitches, we participate in
the MSF (Multiservice Switching Forum) and Parlay’s interconnectivity events, and also offer proposals for application programming interfaces.
E: How do you think NTT is regarded from outsideof Japan?
S: NTT has many leading technologies in this field,
and attracts considerable attention even on an international scale. We are recognized as world leaders inmany technical areas and known for our active participation in scientific conferences and standardization forums. For example, the Certification Working
Group is expected to play a central role in Logo Committee activities at the recent IPv6 Forum, and we feelthat our activities have been very well received there
as well. As a result, we have received many requests
for meetings to exchange ideas and opinions. Given
the evolution of new technologies, corporate competition, and other conditions currently facing theindustry, we are very much aware that the eyes of theworld are upon us.

Being trend-setters in our own field andcreating new innovations
E: What types of research themes have you been
involved in up to now?
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S: My original field of specialization was mathematics, and in graduate school I was working on approximate analysis in Banach space using function theory.
The reason I came to NTT was that I wanted to contribute to society through research that would be useful in real-life situations. NTT covers a wide range ofactivities, from fundamental research to appliedresearch, so I felt that I would have many opportunities to do something useful. For a long time after I
entered the company, I was working on research targeting practical applications of large-scale network
software in new node systems—that is, in the switching segments that form the basis of communication
systems. There are many different types of switchingsystem technologies, but my work focused mainly on
circuit switching, packet switching, and ATM switching. The technologies used in the Internet are a combination of packet and ATM switching. I was very
lucky to be able to work for so many years on technologies that are being put to use now.
E: What are your aspirations as a researcher?
S: The thing that has been on my mind most recentlyis that I want to be able to handle change well. The
world is changing every moment, and we must beable to adapt to those changes flexibly. As
researchers, though, there’s no reward in just chasing
after changes all the time. We always feel that wewant to put something into the field in which we areworking. To do that, of course, we must also work at
getting our vision accepted at scientific conferences
and seminars, but if the result is that the technologies
we have developed actually change people’s lives, weare really motivated. My greatest hope is to be able tocreate innovations in the future—like those brought
about by the mobile phone—and to contribute tosociety in the process.
E: How do you see the NTT Laboratories?
S: To me, NTT is like a bottomless treasure chest ofresearch opportunities. Even more, though, it’s aplace where I can find many outstanding researchers
in a wide range of fields. Participating in discussions
with many different specialists, there’s always something new to learn, and because I can maintain abroad perspective in this way, it’s relatively easy tokeep myself on track in my own research. In research,
you sometimes have to take detours, but if you don’t
stay focused on your own field, then you run the risk
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R&D Spiritsof getting off track and not finding your way back.
Working at NTT has allowed me to come as far as I
have, even though I’ve made detours along the way.
The most important thing is to take advantage of thisgreat research environment, maintain a positive attitude, and just keep moving ahead steadily, one step at
a time.

Interviewee profile■ Career highlights
1980 Graduated from Waseda University, Graduate
School of Science and Engineering (Masters Program); entered NTT Public Corp. (now NTT Corp.)
Worked on DDX packet switching and circuit switching systems and research targeting practical applications of DDX operation systems. From 1991, worked
on research targeting practical applications of ATMswitching systems.
Currently engaged in research targeting practicalapplications of mobile IP, P2P, and Softswitches.
■ Major awards
1994
NTT President’s Award
1995
Laboratory Director’s Award
1996
Laboratory Director’s Award
1999
NTT President’s Award

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