Telecom Cables for Monitoring:
Reconciling Differing Objectives
Simon Webster
NEC
simon.webster@emea.nec.com
Discussion Points
▐ Telecoms meets Monitoring
▐ Perspectives from Japan’s submarine monitoring networks –
an update
▐ Views on the way forward
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Differing Motivations
▐ Telecoms
▐ Dedicated use – reliable
global connectivity
▐ Landings determined by
projected traffic demand,
politics, budgets
▐ High up-front CapEx, low
OpEx
▐ Operational life 25+ years
▐ Maximising design capacity
within budget
▐ Network availability a priority
▐ Currency – IRUs
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▐ Disaster Warning
(e.g. Seismic/Tsunami)
▐ Dedicated use – civil protection
▐ Locations determined by
naturally-occurring geology
▐ High up-front CapEx, moderate
OpEx: natural events require
repairs to cable
▐ Operational life targeted at
approx. 25 years
▐ Fixed bandwidth demand
▐ Non-availability = human risk
▐ Currency – human life,
infrastructure, prosperity
▐ Environmental Monitoring
(e.g. Ocean Climatology)
▐ Flexibility of use has value scientific objectives may evolve
over lifetime of observatory
▐ Project duration ~5 years, hope
to extend
▐ Funding released annually
▐ Future bandwidth demand
unknown (but probably everhigher)
▐ Data outages may be tolerable
▐ Currency – data Æ knowledge
Æ global sustainability
Differing Motivations – Marine Impacts
▐ Telecoms
▐ Disaster Warning
(e.g. Seismic/Tsunami)
▐ Environmental Monitoring
(e.g. Ocean Climatology)
▐ Safest routes
▐ High risk routes
▐ ‘Interesting’ routes
▐ Shortest routes for cost
and latency reasons
▐ Meandering routes
▐ Type, location and spacing
of sensors can vary
▐ Cable burial or other
protection where
necessary to ensure
availability
▐ Surface laid cable (but selfburial possible)
▐ Expect periodic maintenance
in case of seismic activity
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▐ Marine fouling possible
▐ Annual sensor upgrades or
maintenance may be
necessary/desirable
▐ Design for minimal
maintenance
In-line
▐ Wet-mate connectors in
scope
In-line
Nodal
In-line system
Ocean Bottom Seismometer
(OBS)
Terminal Equipment
Cables & Fibres
①
②
③
①: Armored Cable
②: Light Weight Cable
③: Light Weight Screen Cable
①
③
OBS
②
PG
OBS
Provided by JAMSTEC
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Node System
Terminal Station
BU
BU
TE
TE
NODE
NODE
: Wet Mateable Connector
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Sensor
Group 2
Sensor
Group 1
Sensor
Group 2
Sensor
Group 1
Existing Observation Networks in Japan
▐ Long history – first system built in 1979
▐ Early Detection of Earthquakes and Tsunamis
▐ Real-time Data Transmission to On-shore Stations
▐ 24/7 Ocean Bottom Observation
▐ Contribute to Disaster Management through Early
Warning to the Public
▐ All dedicated systems: no dual use cables have
been built
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New Observation Networks in Japan
▐ Planned and funded by the Japanese
Government
5
4
▐ 3-year plan currently under way
▐ Intended for Real-time Observation of
Earthquakes and Tsunamis
3
▐ Over 5,000km of Submarine Cable
▐ Over 150 Undersea Units with
Seismometers and Tsunami Sensors
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2
1
6
NEC Scientific Monitoring System
Seismic and Tsunami Monitor
Optical Submarine
Cable
System Extension
TMU
STM
Scientific NODE
Unit
Economical System
TU
Scientific
Terminal
Equipment
Environmental Monitor
Terminating Unit
Flexible System
Seismic Monitor
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Wet-Mateable
Connector
Hybrid Telecoms and Scientific Monitoring System
Optical Submarine Cable
Non Active Area
High Reliable and/or
Economical System
Terminal
Equipment
Scientific NODE
Unit
ST
M
Geophysical Activity
Area
Seismic
Monitor
Terminating Unit
Multi-Purpose
Monitor
Flexible
System
Geophysical Activity
Area
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© NEC Corporation 2013
Conclusions
▐ Japan’s Experience
z Submarine cable based monitoring systems have been used for over 30 years in
Japan
z Those systems have proven effective for real-time monitoring of seismic
activities and tsunamis
z Built as dedicated monitoring and observation systems, not with commercial
telecommunications capabilities
▐ Current Practical Thoughts
z Dual use cables are technically feasible
z Motivations and practices differ between telecom and monitoring communities
z Some measure of separation between telecom and monitoring systems seems
to be the most practical approach today
z Further discussion and collaboration may advance these arguments
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© NEC Corporation 2013