Fraunhofer HHI
WP 6
HHI Contributions to WP 6
Deliverable D24
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
Optical layer of multi-service/multi-layer networks with focus on optical
bypass nodes:
•
Description and analysis of various wavelength switching node
architectures
– Alternative technological options
– Analysis of the architectures
• Detailed description of the architectures
• Comparison and assessment of the solutions
• Evolutionary trends
•
Multi granular (waveband, wavelength) optical architectures
– Technological options, hardware complexity
– Wavelength conversion
– Potential benefit
•
Specific Component Analyses
– Tunable Transmitters, tunable filters, wavelength converters
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
OXC without wavelength conversion
Small space switches
-Demux
1
 - Mux
1
SpaceSwitch
1
1
M
1
M
1
Drop
Add
M
1
M
1
1
SpaceSwitch
M
N
N
M
M
Add
Drop
•
•
•
•
Transparent
Moderately large space switches
End-to-end wavelength assignment
Switching time > 1- 10 ms,
limited by space switch
• Granularity: wavelengths,
wavelength bands, fibers
• Not blocking free on wavelength level
• Possible technologies
• Switch Fabric
- 2D/3D MEMS
• Mux/Demux
- AWG (Silica,Si)
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
Special cases for A2:
•
•
Space switch is built with small MEMS
switches
Space switch is built with a B&S architecture
and blocking switches
N(N-1)M Switches
NxN MEMS
switch
1
1
1
1
1
M
M
1
1
M
M
1
1
M
M
1
1
1
M
M
1
1
N
M
M
N
N
1
M
M
1
Add
Drop
Drop
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Add
N
Fraunhofer HHI
WP 6
Motivation for multi granular (waveband, wavelength) OXC
•
•
•
•
•
Smaller overall size at (nearly) equivalent performance
Better scalability
Smaller size of individual optical switch fabrics
Simpler upgrade
Simpler management
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
Characteristics of Multi-Granularity OXC
• Node Architecture
– Single layer, concurrent switching of bands and wavelength
– Hierarchical, multistage multiplexing and switching
•
Capacity
– Number of fibers, wavelengths
– Capacity of local add/drop ports, granularity levels
• Capacity ratios
– Relative size of waveband switch to wavelength switch
• Transparency
– Waveband switch optically transparent / waveband converters
– Wavelength switch transparent/with wavelength converters/opaque
• Number of wavelength per band/ Number of bands
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
– Wavelengths
– Wavelengthbands
– Fibers
•
F ro m Cien
Dro p B
To Cien ts
Dr o p F
Hierachical combination of optical
cross connects
• Switching at different granularity
levels:
Dro p W
Ad d W
WXC
Mux
W  B
De mu x
B  W
Sp a ce - s w itc h
Different losses (signal quality)
for switched fibers, wavebands,
wavelengths
BXC
Mux
B F
De mu x
F B
Sp a ce - s w itc h
Source:
Multi-Granularity Optical Cross-Connect
L. Noirie, C.Blaizot, E. Dotaro; Alcatel, France;ECOC 2000, Proceedings Vol 3, pp 269-270
p u t 2005
NOBEL WP 6 Meeting JuneIn13-15,
Munich f ib res
FXC
O
fi
Fraunhofer HHI
WP 6
Single-layer, multi-granular OXC
•
•
•
•
No flexible change of granularity,
Wavebands and wavelengths
pre-designated
All signals pass switching fabric
only once, same optical losses
for all signals
Simpler than hierarchical
counterpart
Can be even more efficient than
hierarchical counterpart
Waveband add/drop
Waveband
Switch
Wavelength
switch
Wavelength add/drop
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
L. Noirie, The road towards all-optical networks, OFC 2003, Vol 23, pp 615-616
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
MG-OXC with cyclic MUX/DMUX
wavelength stage
•
-switch
Flexible choice of
wavebands, to be
switched on wavelength
level
– One larger size WBswitch
– Cyclic wavelength
muxdemux needed
cyclic
-MUX/DMUX
WB
WB-switch
waveband
MUX/DMUX
FWB
Input fibre
waveband stage
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
Analysis and comparison of different architectures of MG optical nodes:
• Hardware complexity / Cost
– Port count
– Component count
– Key components
• Switch fabrics (2D/3D MEMS)
• Band multiplexers
• Cyclic AWG (for MUX/DeMux of wavelength from any waveband)
• Physical Limitations
– Causes of degradation
• Loss, loss differences (especially hierarchical switch), crosstalk
– Maximum capacity
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
Comparision of different node architectures:
• 4 fibres, 8 wavebands, 8 /waveband  256 channels
• 50% add/drop traffic
•equal partition of band and wavelength switching
Node type
Elec. OXC
SL-MG-OXC
H-MG-OXC
Cycl. MG-OXC
#
#
Reduction
#
Reduct
ion
#
Reduction
WB-switch
-
4x5x5
-
8x8x8
-
4x16x16
-
-switch
-
32x5x5
-
64x3x3
-
32x6x6
-
E-switch
1x256x256
-
-
-
-
-
-
S Ports
256
180
-30%
256
0%
256
0%
S switching
elements2)
65536
900
-98.6%
1088
-98.3%
2176
-96.7%
WB-MUX
8
8
0%
8
0%
8
0%
-MUX
64
32
-50%
32
-50%
NOBEL WP 6 Meeting June 13-15, 2005
Munich
32
-50%
2)
for square matrices
Fraunhofer HHI
WP 6
Key components for MG-switching nodes:
requirements, characteristics, availability
• Band multiplexer/demultiplexer
– Thin film interference filter is preferred technology
– Steep edges compared to filter bandwidth
• Guard band, skipping of wavelengths between bands
– Available from several vendors
• Cyclic multiplexers/demultiplexers
– Cyclic characteristic over all bands
– No guard bands
• Wavelength band converters (rather exotic till now)
– Signal quality (noise figure, distortion)
– Complexity
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
Filter Components - banded filter
• cascaded configuration for Waveband MUX/DMUX
4 skip 0
4 skip 0
4 skip 0
4 skip 0
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
Filter Components - banded filter
• Thin film interference filter is preferred technology
• various configurations possible (n-skip-m notation)
– 25 GHz:
8skip1, 16skip3, 39skip4, 78skip8
– 50 GHz:
4skip0, 7skip1, 8skip1, 8skip2, 16skip3
– 100 GHz:
2skip0, 4skip1, 4skip0, 5skip1, 8skip2
– 200 GHz:
4skip2, 4skip1, 4skip0
• Steep edges compared to filter bandwidth (esp. nskip0 type)
– Guard band, skipping of wavelengths between bands
– Loss, ripple, dispersion
• Available from several vendors (Bookham, JDSU, Avanex, …)
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
Filter Components – colourless (cyclic) AWG MUX/DMUX
1 ...
9 ...
·
8
16
1, 9, ...
·
cyclic
AWG
8, 16, ...
Transmission [dB]
8-skip-8x50 GHz Demux Spectrum
Frequency [THz]
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Source: Gemfire Corp.
Fraunhofer HHI
WP 6
Filter Components – colourless (cyclic) AWG MUX/DMUX
• Silica on silicon technology
• Available from different sources (ANDevices, NeoPhotonics, …)
• various configurations available
– 4, 8, 16 channels
– 50 and 100 GHz channel spacing
– Available without guard bands
• Issues:
– Filter order limited 5…8
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
Contribution to D24:
• Physical layer analysis of multi-granular switching nodes
– Key components
• Definition of requirements
• State of the art characteristics
• Availability
– Assessment of reduction in hardware complexity
• Port count
• Component count
• (Cost estimate)
– Physical limitations, scalability
NOBEL WP 6 Meeting June 13-15, 2005
Munich
Fraunhofer HHI
WP 6
Specific Component analysis
• Tunable Lasers (Transponders)
• Tunable optical filters
– Requirements
– State of the art characteristics
– Newest developments
NOBEL WP 6 Meeting June 13-15, 2005
Munich