Transcript 4 - Introduction aux réseaux par satellite

Réseaux et Télécommunications
4 - Introduction aux réseaux par satellite
Edoardo Berera
Telelinea
Plan
• Orbits and coverage: GEO, MEO, LEO
– Broadcast, point-to-point
– “Bent-pipe” vs. on-board processing
• Examples
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Iridium
Globalstar
EuroSkyWay
SkyBridge
Teledesic
Sky Station
e-BIRD 1
Satellites
• From Sputnik... to military
– Since the first russian Sputnik satellite in 1957 :
• 5000 satellites have been launched
– 2500 are still in orbit
• Half of them are used by the military
Civilian usage
• The remaining ones (> 1200) are used for:
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telecommunications (Telecom-1, Telecom-2,...)
television (Astra, HotBird 5, ...)
meteorology (Meteosat, Med Hycos)
earth observation (Landsat, Spot)
astronomy (Hubble)
• 2000 are expected to be launched in the next 10 years,
including a number of satellite constellations.
Orbits
• GEO Geostationary
(or geosynchronous) :
– 36000 km
• MEO Medium Earth Orbit :
– 1500 - 10000 km
• LEO Low Earth Orbit :
– < 1500 km
Coverage
Broadcast
“Bent Pipe” (Mirror)
– VSAT Very Small Aperture Terminal
– Terrestrial Switching Center
– Two bonds
X
On Board Processing (Switching)
– One bond
x
Iridium
• Consortium:
– Motorola main contractor
• Operational service since November 1998
• $ 5 bn, 7 years
• 66 LEO fast-moving satellites (+ 14 spares),
– 780 km
– Unique inter-satellite "cross-links"
• 11 earth stations
Globalstar
• Consortium
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Loral Space and Communications
Qualcomm
France Telecom
Vodafone Group (UK)
Hong Kong Telecom
• Service operational since September 1999
– $ 3 bn
– 48 LEO satellites (+ 4 back-up), 1400 km
– 50 earth stations
• Primary market is "cellular network extension"
• Call price: 0.70 €/min
EuroSkyWay
• Aggregate capacity
– 45 Gbps
– cluster of five satellites
– geostationary satellites
• Digital on-board processing
(OBP)
• Inter-satellite links (ISL)
• Alenia Aerospazio
Terminals
Coverage and antennas
Africa and West Asia
SkyBridge
• Consortium:
– Alcatel
– Loral Space &
Communications
– Toshiba
– Mitsubishi
• Constellation
– 80 LEO satellites
– 1469 km
• Space segment cost: $4.2 bn
• Ground segment cost: $1.9 bn
• By working through local
operators, SkyBridge is
positioned as
– a local access system, “DSL
in the sky”
– solving the "last mile
problem" as well as
– providing Universal Service
worldwide
• low cost terminals ( < $500)
• 20 Mbps down-link / 2 Mbps
up-link per residential user
• 100 Mbps down-link / 10
Mbps up-link per business
user
Teledesic Project
• Bill Gates (Microsoft)
– Craig McCaw (McCaw Cellular
now sold to AT&T)
– Prince Alwaleed of Saudi Arabia
– Boeing and Motorola
• Initially 840, now down to 288
LEO satellites at 700 km
• $ 9 bn
• Subscribers service at 64 Mb/s
downlink and 2 Mb/s uplink
• Broadband terminals at 64 Mb/s
bidirectional
Sky Station Project
• Telecommunications
• Earth Sciences Applications
– 250 Sky Stations (157 x 62
m)
– 22 km (stratosphere)
– coverage 20 000 km2
– 2 - 10 Mb/s
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Alenia Aerospazio
Thomson-CSF
Daimler-Benz Aerospace
COMSAT Laboratories
United Solar Systems Corp
e-BIRD 1
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Eutelsat, Paris
Boeing satellite
Ariane 5 launch Sep. 2003
Operational Nov. 2003
Internet broadband service
References
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Aleniaspazio EuroSkyWay
Globalstar
SkyBridge
Teledesic
Sky Station
Eutelsat
• http://www.ee.surrey.ac.uk/Personal/L.Wood/
constellations/orbcomm.html
High Speed Networks
5 - Fiber Optic Networks
Edoardo Berera
Telelinea
Plan
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Fiberoptic cables
UNSA: ATM & Gigabit networks
Renater 2
NTI
TEN-155 / GEANT
FLAG
SEA-ME-WE 3
Project OXYGEN
Fiberoptic Cables
UNSA
• Backbone
– ATM 155 Mb/s
• User access
– IP over ATM
– Ethernet 10/100 Mb/s
UNSA
• Backbone
– ATM 155 Mb/s
• Evolution to Gigabit/s
campus network
– Tests Commutateurs
Gigabit Ethernet
• User access
– IP over ATM
– Ethernet 10/100 Mb/s
Gigabit Ethernet
Renater 2
• Réseau National de
Télécommunication
pour l’Enseignement et
la Recherche
• IPv4 et IPv6 (G6)
NTI
• Noeud de
Transit
International
TEN-155
• Trans-European
Network
• 155 Mb/s
GEANT
FLAG
• Fiber Link Around the Globe
FLAG Cable
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Two fibre pairs - each operating at 5 Gb/s.
Over 28,000 kilometres of cable.
120,000 digital circuits operating at 64 kb/s.
Up to 600,000 simultaneous conversations per segment.
326 erbium-doped optical amplifiers.
Four fibre-switched branching units.
Diversely routed land crossings - two in Egypt and two in Thailand.
Operational since November 22, 1997
Installed and commissioned in 27 months
Cost 1.5 B$
Erbium doped optical amplifier
Source: IEEE Spectrum
SEA-ME-WE 3
• South East Asia-Middle East-Western Europe 3
– Germany to Australia, Taiwan, Korea and Japan
• operational since August 30, 1999
• 38 000 Km, 2 pairs of fibers
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direct optical amplification
wavelength division multiplexing (WDM)
8 wavelengths (colors) per pair of fibers
bypass units allow the insertion/extraction of one or two colors per
fiber
– 30 000 telephone circuits per wavelength
– 483 840 digital 64 kb/s circuits
• 33 countries, 25 years of lifetime, 1.5 B$
WDM and DWDM
• Wavelength Division Multiplexing
• Dense Wavelength Division Multiplexing
Source: S.V. Kartalopoulos, « Introduction to DWDM Technology: Data in a Rainbow », chapter 5, IEEE/SPIE
Project OXYGEN
• Neil Tagare, the originator of the FLAG cable
– Bechtel Corporation is OXYGEN's project manager
– Lehman Brothers serves as its financial advisor
• 169000 km
• DWDM technology
• 2.56 terabits of capacity
• 97 landing points in 76 countries
• Initial budget 15 B$
Landing Points
• Phase 1B
– Egypt - Port Said
– Egypt - Alexandria
– France - Antibes
– Gibraltar - Gibraltar
– Greece - Athens
– Ireland - Dublin
– Israel - Tel Aviv
– Italy - Genoa
– Italy - Lido Di Ostia
– Lebanon - Beirut
– Malta - Valletta
– Monaco - Monaco
– Spain - Conil
– Spain - Barcelona
– Syria - Tartus
– Tunisia - Tunis
– Turkey - Izmir
– U.K. - Fareham
– U.S.A. - Tuckerton
Project OXYGEN
• Subscription price
– 10 M$ for 1.24 Gb/s network access for 25 years
– plus 9% per year for Operations and Maintenance of Network and
Terminal Station
References
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CRI, UNSA
Renater
DANTE
FLAG
FCR
Project OXYGEN