IP over OPTICAL ITU-T Workshop July 2002 Optical Switching And Equipment

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IP over OPTICALITU-T WorkshopJuly 2002Optical
Switching And Equipment
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Agenda

• Overview Of Optical Switching Techniques
• Optical cross-connects based on Electrical
  switching technology
• Optical cross-connects based on Photonic
  switching technology
• In opaque context
• Toward fully transparent networks

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Agenda

• Overview Of Optical Switching Techniques
• Electrical switching technology
• Photonic switching technology
• In opaque context
• Toward fully transparent networks

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Benefits of the fully transparent networks

• Two core switching technologies are available for
  providing flexibility in the OTN
• Electrical
• medium size cross-connects (lt512 lambdas)
• Photonic
• allow bigger size in opaque context (thousands of
  ports in future)
• key element for all optical networks
• The operator choice is driven by the overall
  network cost and depends strongly on the network
  itself (topology, traffic matrix) and the
  application

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Optical Switching Techniques And Network
applications overview
LTE/ Vendor A
LTE/ Vendor B
- Electrical fabric with black white O/E
ports - Multi-vendor solution, cope with WDM
installed base - pre-OTN or full G.709 management
Electrical
O/E
O/E
O/E/O
O/E/O
OXC/ Vendor C
- Electrical fabric with colored O/E ports -
Mono-vendor solution - full G.709 management (and
pre-OTN)
Electrical
O/E
O/E
OXCWDM/ Vendor C
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Optical Switching Techniques And Network
applications overview
LTE/ Vendor A
LTE/ Vendor B
- Optical fabric without O/E/O ports - O/E/O
ports in WDM - Multi-vendor solution - Partial
G.709 management
Photonic
O/E/O
O/E/O
OXC/ Vendor C
- Optical fabric without O/E ports - no O/E/O
ports in WDM for pass-through traffic -
Mono-vendor solution - Partial G.709 management
Photonic
OXC WDM Vendor C
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Agenda

• Overview Of Optical Switching Techniques
• Electrical switching technology
• Photonic switching technology
• In opaque context
• Toward fully transparent networks

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Optical Switching TechniquesElectrical
technologie
- Cross-connects with integrated colored WDM
transponders () full access to the G.709 frame
() most cost effective solution (avoid multiple
OEO in the node) (-) mono vendor solution
LTE/ Vendor A
UNI
NNI
NNI
O/E
O/E/O
O/E
OXC LTE / Vendor C
- Cross-connects with black white O/E ports()
allow multi-vendor interoperability (-) G.709
management must be complemented in order to
forward the section Signal Degrade condition
(based on FEC corrected errors) from WDM systems
to OXC (as well as from WDM system to WDM system)

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Agenda

• Overview Of Optical Switching Techniques
• Electrical switching technology
• Photonic switching technology
• In opaque context
• Toward fully transparent networks

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Agenda

• Overview Of Optical Switching Techniques
• Electrical switching technology
• Photonic switching technology
• In opaque context
• Toward fully transparent networks

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Photonic switching technologyOpaque environment
DCI
DCI
- Optical fabric without O/E/O ports- O/E/O
ports in WDM- multi-vendor solution- Large
scale OXC with 3D MEMS techno (thousand of ports)
Photonic
O/E/O
O/E/O
LTE/ Vendor A
OXC/ Vendor C
LTE/ Vendor B
() cost effectiveness for intelligent patch
panel in pre-OTN or OTN environment (-) no 3R
ports in OXC gt only non intrusive monitoring
capabilities (-) OXC ports provide a low level of
monitoring capabilities (optical LOS only) gt a
performant networking application (protection,
restoration) implies to add an alarm forwarding
mechanism from WDM to OXC (DCI).
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Agenda

• Overview Of Optical Switching Techniques
• Electrical switching technology
• Photonic switching technology
• In opaque context
• Toward fully transparent networks

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Benefits of the fully transparent networks

• Cost savings on the transponder side
• Pass-through traffic is switched all optically
  in a node, there are no 3R transponders on the
  signal path gt less 3R transponders in the
  network
• Cost savings on the switching elements side
• Port price of a photonic fabric is the same for
  one single channel or multiple channels gt less
  ports, lower price for an equivalent switching
  capacity
• the combination of a 3R lambda OXC and a photonic
  band cross-connect alleviates the size of the 3R
  OXC
• On typical Pan-European and Pan-American
  networks, around 20 savings can be experienced
  with transparent Band cross-connect

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Transparent NetworksNode Architecture
Photonic
Band 1
Combination of transparent  band  cross-connect
and 3R lambda cross-connect
Band 2
Band MUX
Band MUX
Band n
Band MUX
Band MUX
3R Lambda cross-connect- flexible lambda
grooming- lambda conversion to resolve blocking
Lambda MUX
Intra Vendor Proprietary Interface
..
Lambda MUX
Lambda MUX
Lambda MUX
Lambda Fabric
User Network Interfaces (UNI). 10G, 42.5G
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Key issues in Fully transparent Long-haul networks

• Cascadability of filtering functions
• Only band cross-connect is feasible in long-haul
  applications (8 bands of 10 lambdas)
• Fluctuation of power
• automatic power adjustment when changing the
  (band) provisionning
• Chromatic dispersion adjustment
• Increased tunability range required, need for
  tunable chromatic dispersion on a band basis
• Monitoring issues
• access to digital information in only possible at
  the edge of the network

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Transparent Networks Node Architecture
Building blocks for fully transparent optical
cross-connect - Active Gain Equalization (AGE)
equalize the OSNR degradation, on a section
basis - Tunable Dispersion Compensation -
shared signal quality measurement (for
maintenance activities and fault location)
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Thanks