OFC 2014 Presentation This study proposes CDC ROADM architecture compatible with emerging DWDM super-channel technology. A real world network model is used to quantify that this architecture requires fewer network components leading to less capital and operational costs.

1. Implications of Super-Channels
on CDC ROADM Architectures
Anuj Malik, Wayne Wauford, Zhong Pan, Nitin K Goel,
Steve Hand, Matthew Mitchell
Infinera Corporation, Sunnyvale, CA, USA
OFC 2014

2. 500 GHz
10 λ @ 50GHz
375 GHz
10 λ Super-Channel
DWDM super-channel
• Unified channel of multiple optical carriers
• Provisioned in a single operational cycle
Emergence of Super-Channels
Advantages of Super-Channels
• Very high speed (up to 1 Tb/s)
• Eliminate guard bands between channels
• Increased fiber capacity
• Lower operational complexity
Many recent experiments, field trials, and
deployments
• 400G/500G/800G/1Tb/s
• Over 1Pb/s of deployed 500G super-channels
0
20
40
60
80
100
120
140
160
180
200
2 3 4 5 6 7 8
Terabitspersecond
ROADM Degrees
Capacity of ROADM Node:
Super-Channels vs 100G Wavelengths
Super-channels increase
ROADM scale

3. ROADM Capabilities
Basic ROADM CDC-ROADM
Reconfigurable express &
add/drop (replace
FOADM)
Specific l mux port
1 x mux per direction
Colorless: any channel to
any mux port
Directionless: share mux
between directions
Contentionless: multiples of
same l can be add/drop to
same mux
Colorless-ROADM
Enhances Basic-ROADM
Enables any channel
connected to any mux port
1 x mux per direction
CDC ROADM Provide Truly Flexible Optical Transport Infrastructure

4. Super-Channel CDC ROADM Architecture
Super-channel Routing Module
with Flexible Grid Twin WSS
Line Out
Line In
System 16 IN
System 9 IN
System 9 OUT
System 16 OUT
System 1-8 IN
System 1-8 OUT
1X16
WSS
1X16
WSS
Super-channel Switch Modules,
Multicast Switch (MCS) based
8 Line In/Out ports
16 Add/Drop In/Out ports
Dual 8x16 Multicast Switch
• Flexible Grid: support super-channels > 50GHz
• Colorless: any super-channel to any mux port
• Directionless: share mux between directions
• Contentionless: multiples of same l can be
add/drop to same mux
Super
Channel
FSP-AD
Amp
Express channels
Add/Drop channels
North
West East
Amp
Super
Channel
Super
Channel
Super
Channel
Super
Channel
Super
Channel
Super-channel
Switch
Modules
Amp
MCS MCS MCS
FSP-E
WSS WSS
FSP: Fiber Shuffle Panel for MPO fibers
Super-channel
Routing Module
Route and Select
Architecture

5. Super-Channel CDC ROADM Simplify Networks
 Super-channels are higher capacity than single λ
• e.g., 400G, 500G, 800G, 1Tb/s
 Significantly less Routing and Switching Module
ports
• Compared to wavelength-based
 Example: 1 Tb/s
• Two 500Gb/s super-channels
• Ten 100Gb/s wavelengths
• 2 vs. 10 add/drop ports
Node-level Comparison
4 degree CDC ROADM with Full Add/Drop
100G Waves
500G Super-
channels
# of Switch
Modules
24 5
# of Routing
Modules
8 4
Total 32 9 CDC ROADM diagrams based on S. Gringeri et al.,
“Flexible Architectures for Optical Transport Nodes
and Networks,” IEEE Communication Magazine,
Vol. 48, no.7, July 2010, p.40

6. Super-channel CDC ROADMs NetworkStudy
North American Long-haulNetwork Model
Traffic Types
• City-to-city
• Data Center-to-Data
Center
• International traffic from
submarine cables
40% annual growth
# of Nodes 87
# of Spans 434
Average Node Degree 2.6
Max Node Degree 5
Total Fiber Distance 32,130km

7. Super-channel CDC ROADMs NetworkStudy
500G Super-channelsvs. 100G Wavelengths
Assumptions:
• CDC ROADM (up to 8 degrees)
• 1x16 WSS for Routing Module
• 8x16 MCS for Switch Module
• Integrated OTN switching
• 100G line module
• 500G super-channel line module
# of Super-channel vs 100G line modules
per year
0%
200%
400%
600%
800%
1000%
1200%
Year 1 Year 3 Year 5
#ofLineModules
(usingYr1S-CLMsasthebase)
Super-Channel Line Modules
100G Line Modules
# of Super-channel vs 100G ROADM elements*
per year
0%
50%
100%
150%
200%
250%
300%
350%
400%
Year 1 Year 3 Year 5
#ofROADMElements
(usingYr1S-CROADMasthe
base)
Super-Channel ROADM
Wavelength-based ROADM
*ROADM elements = Routing and Switch Modules

8. Conclusion
• Emerging technology
• Network scale
• Ease of operation
Super-channels
• Colorless, Directionless, Contentionless
• Most flexible and efficient optical transport
CDC ROADMs
Super-channel
CDC ROADM
• Flexible Grid
• Significantly fewer ROADM elements
• Less operational complexity
Super-channel CDC ROADMs simplify networks

9. Thank You