NTT’s Ultra-High-Speed Networking
Experiment on Real-time VLBI
Joint Trials with CRL, NAOJ and ISAS (KSP and GALAXY)
Hisao Uose, Kazunari Irie & Sotetsu Iwamura
NTT Laboratories
History
• A part of NTT’s Ultra-High-Speed Networking Research
Project which started in June 1995
• “Real-time VLBI” is a joint effort of NTT Laboratories,
Communications Research Laboratory (CRL), National
Astronomical Observatory of Japan (NAOJ) and Institute
of Space and Astronautical Science (ISAS)
• We’ve built a large-scale dedicated network spanning
Kanto/Shin-etsu areas (total fibre length was about
1,000km) connecting radio telescopes and processing units
with OC-48 (2.4Gb/s) circuits, ATM Switches and highperformance IP and started its operation in 1996
4/18/2002
Hisao Uose, NTT Laboratories
Why do we (NTT) do this????
• Establish technologies for very high speed
communications (Gb/s class for each application)
– We’ve developed a special purpose network equipment for the trial
• Explore the effectiveness of ultra-high-speed
communications technologies in advanced science and
create new communications application
• Contribute to Science and Society
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Hisao Uose, NTT Laboratories
Real-time VLBI Applications
• Geodesy (KSP: Key Stone Project)
– High precision crustal deformation measurement system using
realtime VLBI in Kanto Area
– Challenges for advanced earth science and precise space
navigation technologies
• Radio astronomy (OLIVE & GALAXY Projects)
– Ultra-high resolution/sensitivity radio telescope combining VLBI
and Gigabit class networks
– Challenges for opening a new vista of radio astronomy
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Hisao Uose, NTT Laboratories
GALAXY/KSP Network
Radio Frequency Signals from
Space
Usuda Deep
Space Center
(ISAS)
Nobeyama Radio
Observatory (NAO)
KSP Miura
Station (CRL)
KSP Kashima
Station
2.4Gb/s ATM Network
Kashima Space Research
Center (CRL)
NTT Musashino
R&D Center
KSP Tateyama
Station (CRL)
KSP Koganei
Station
National Astronomical
Observatory
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Communications Research
Laboratory
Hisao Uose, NTT Laboratories
GALAXY/KSP Network: Geographical View
ISAS Usuda Deep
Space Center (Nagano)
NTT Musashino
R&D Center
Ibaraki
NAOJ Nobeyama Radio
Observatory (Nagano)
Tokyo
CRL (Koganei)
Kanagawa
Dedicated Network
OC-48 (2.4Gb/s)
OC-48 x n (with WDM)
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NAOJ
(Mitaka)
Chiba
208km
Hisao Uose, NTT Laboratories
CRL Kashima
Research Center
Antennas Used for our Experiments
Nobeyama 45m
Kashima 34m
Usuda 64m
11m antennas for KSP
(Koganei, Tateyama, Miura, Kashima)
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Hisao Uose, NTT Laboratories
(Simplified) Logical Network Configuration
Under construction
BV-3000
BV-3000
ASX1200
M20
NAOJ Nobeyama
BV-3000
CRL
(Koganei)
BV-3000R
ISAS Usuda
NTT Labs
(Musashino)
ASX4000
ASX4000
GR2000-20
M20
BV-3000R
ASX4000
BV-3000
GR2000-20
CRL Kashima
ID1 I/F to
connect samplers
and correlators
Network Equipment
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NAOJ
(Mitaka)
M160
BV-3000R
BV-3000
Disconnected (11/02) CRL Tateyama
ATM NW IF
ATM-SW Router
Network Interface ATM
Hisao Uose, NTT Laboratories
GbE
KSP: Geodesy using Realtime VLBI
• NTT joined the CRL’s Key Stone Project (KSP) to help
them achieve the very high resolution measurement
system of crustal deformation in Kanto area using
realtime VLBI in 1995
• Regular (every other day) measurement has been
conducted until November 2001 and the obtained data
were utilized for the research of earth science
– A major deformation due to a sudden volcanic activity around Izu
Island has been observed last year
– A large amount of measurement data is publicly offered to earth
science community through the CRL web site
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Hisao Uose, NTT Laboratories
KSP Measurement Sites in Tokyo Area
36 N
139 E
Koganei
35 N
58 km
92 km
4 cm/year
135 km
35 km
Tateyama
m
th A
r
o
N
10 cm/year
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140 E
123 km
Miura
Philippine sea
plate
109 km
Kashima
e
plat
n
a
eric
lat
p
ific
c
a
P
Hisao Uose, NTT Laboratories
e
141 E
Ultra-high Resolution Radio Telescope
• Started as NTT･NAOJ･ISAS project (OLIVE) to
implement the largest virtual radio telescopes using
multiple terrestrial/space antennas with realtime VLBI
• Flexible and precise observation can be obtained only with
realtime data transmission and processing
– First fringe (cross correlation) was detected in 1997 between the
signals received by a terrestrial antenna (Usuda) and a satellite
antenna (HALCA)
– Realtime correlation has been successfully established among
large terrestrial antennas (Usuda, Nobeyama and Kashima) in 1998
• GALAXY started as a joint project of KSP and OLIVE in
1999
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Hisao Uose, NTT Laboratories
Significance of Our Observation System
• The first realtime VLBI system using ultra high speed
digital communications networks (several Gb/s)
• High sensitivity/resolution obtained by high-speed
connections
– The sensitivity obtained of our system is comparable to the
highest sensitivity achieved (5~10mJy) which is only available on a
magnetic tape-based system (non-realtime)
• Flexible Observation with realtime data processing
– Experiment plan can be easily rescheduled according to the
results obtained with the realtime observation
• Experiment support system utilising multimedia
conference system and ultra high speed networks
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Hisao Uose, NTT Laboratories
Future (1): Upgrading Connectivity
• Performance Upgrade with Higher Data Transmission Rate
– We’ve succeeded an experiment with higher speed (1Gb/s) last
year which outperforms any system in the world
• Addition of Antennas
– Addition of other antennas to the GALAXY network are being
sought which improve both sensitivities and resolution of the
resulting radio telescope
• International Cooperation
– We are seeking the possibility of international cooperation with
research organizations abroad including MIT Haystack
Observatory and the Internet2 project
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Hisao Uose, NTT Laboratories
Future (2): Internet-based VLBI
• Adoption of very high speed IP technology to realtime
VLBI, which will make the realtime VLBI observation more
economical and widespread
– High speed IP stream transmission system applicable to the
realtime VLBI has been developed
– Distributed processing utilizing a huge number of PCs on the net
should be very interesting as well (just started)
• Supporting tools for distributed realtime VLBI
observations
– Multimedia conferencing system using IP Multicast
• The standardization of interface between data
acquisition/processing units and network is crucial for
Internet VLBI
– Expansion of VSI (VLBI Standard Interface) ??
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Hisao Uose, NTT Laboratories
Supporting Environment for Observation
･ Sharing of critical information among participating sites is a must
･ Multimedia Communications tools with IP multicast is being tested
･Multicasting of radio signal is interesting for distributed processing
Chat
Router
GALAXY Network
Router
Router
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Hisao Uose, NTT Laboratories
Future (3): Cooperation with Other Projects
• Cooperation with Internet2 project
– NTT is a Corporate member of I2 since 1998
– GEMnet has been connected to Abilene (I2 backbone) this year
• Cooperation with ASTE/ALMA project and U. Chile
– NTT started to cooperate in developing new photo detectors and data
processing technologies applicable for ALMA/ASTE project
– NTT has been working with University of Chile which is helping the ALMA
project in Chile (AccessNova Project) for over five years
– High-speed link between Chile and Japan has been established with
Internet2’s ITS (International Transit Service) to REUNA via AMPATH
• New research initiative within NTT labs
– We’ve started to cooperate with other sections of NTT Labs to
accelerate R&D with “synergy” effect
– “AWG-STAR” photonic device and HD video transmission system are
alredy deployed in our network
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Hisao Uose, NTT Laboratories
GEMnet-Abilene Connections
Seattle
（Abilene: Backbone Network of Internet2）
Sunnyvale
Connection Point
（OC-3）
ps ilene）
b
33Mfor Ab
bps
M
0
（1
To
an
p
a
J
Chicago
Sacrament
Los Angeles
San Jose
Kansas City
Denver
6.5Mbps
New Jersey
Atlanta
Houston
・Connections through STARTAP (April 2001) and
Sunnyvale (June 2001)
・Connectivity to 187 I2 member universities
・International Transit Service which enables us to
connect 15 other academic networks
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Indianapolis
Abilene
GEMnet
Node
Cleveland
New York
: GEMnet ATM circuits
: Abilene Backbone
: Abilene Core Routers
Hisao Uose, NTT Laboratories
Cooperation with NAO and U. Chile
Remote monitoring/control of ASTE/ALMA telescope will start soon
with the cooperation of Internet2(Abilene), AMPATH and REUNA2
m
ASTE 10m Prototype Telescope
at the height of 4,800m
NAOJ ALMA
Base Station
San Pedro
de Atacama
National
Astronomical
Observatory
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Japan
NTT Labs
Musashino
Trans Pacific
US
Trans Americas
GEMnet
Abilene
AMPATH
Chile
REUNA2
Hisao Uose, NTT Laboratories
U. Chile
Network Upgrade with WDM Technologies
Nobeyama
Usuda
Kashima
NAOJ
NII
8 Lambdas
NTT Yokosuka Labs
Optical device
(AWG-STAR)
8 Lambdas
CRL
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8 Lambdas
NTT Musashino Labs
Optical XC
NTT Com
Hisao Uose, NTT Laboratories
NTT Atsugi Labs
Conclusion
• We did very well considering the limited resources
– Though, we might have been able to do more!!
– and, other groups are working very hard!!
• Necessity of widening our perspective in technological
sense
– “Network computing” can be another big business for NTT
– GALAXY could be a nice testbed not only for advanced networking
technologies but also for those new middleware and applications
technologies
• and cultural aspects
– International collaborations (and joint effort in general) will
multiply the results of each participating group
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Hisao Uose, NTT Laboratories