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Ciena has always been a firm believer in SCinet’s pivotal role in putting leading-edge technology to the test. Keeping with this tradition, Ciena offered to support the SC13 WAN group with 400G transponders. ESnet and Internet2 had bandwidth requirements that could potentially fill the 400G WAN pipe. Today, we will describe the technology and its benefits and relate these benefits to the SC13 WAN activity.

ConstellationMultiplicity

Symbol Rate

SubcarrierMultiplicity

WL1 WL2 WL3 WL4

Dependent on new technologies

Spec

tral

effi

cien

cy a

t the

co

st o

f rea

ch

Embedded software intelligence key for operational simplification & flexibility

Programmable Modulation

Embedded Intelligence

Tx DSP allows single chipset to support many modulations Ability to optimize link based on capacity and reach Operator control for maximum flexibility

Integrated test set capabilities for faster turn-up Continuous real-time reporting and system optimization Ability to operate over any fiber Fast coherent receiver switch times

Soft Decision Forward Error

Correction

Spectral Shaping

Required for closest packing of sub-carriers in SuperChannel implementation

Provides strong tolerance to cascaded filters for maximum throughput

Required to offset performance degradation from higher symbol rate, constellation multiplicity

Correction algorithm based on probabilities Theoretical OSNR improvement – up to 3dB

0 or 1

Time Domain Frequency Domain Wide Spectrum (w/ sidebands)

Narrow Spectrum: - Traverse more ROADMs - Improved spectral efficiency - More channels with Flexible Grid

Eb/No (Input signal to noise ratio)

BER

•Eliminate bit errors •Improve system reach

Lots of noise

Little noise

1

10-16

)0()1(log

yprobabilityprobabilit

Hard Decoding uses single decoded bits Soft Decoding uses probabilities

Soft decoding needs many more gates.

Soft Decoding can theoretically achieve 3dB better performance

0 or 1

4.8 bits/second/Hertz

• Symbol rate captured from Rx after 300 km

• Production WaveLogic 3 Hardware • 10GE test set; traffic daisy-chained

• Error Free, even during transitions

Once everything is mixed together you get SuperChannel Technology

75 GHz

400G SuperChannel (DP-16QAM) 1T SuperChannel (DP-16QAM)

200 GHz

16QAM 16QAM 16QAM 16QAM 16QAM 16QAM 16QAM

100 Gb/s channels at 50 GHz grid (ex. DP-QPSK))

50 GHz

Wasted Filter Guardband

DP-QPSK DP-QPSK DP-QPSK DP-QPSK DP-QPSK

Fixed Grid System

Flexible Grid System

Ref.: http://my.es.net/demos/sc13 Ref.: http://sc-monitor.internet2.edu/sc13_utilization/ ?rtr=wan.cfg&bars=Cami&xgtype=w&page =graph&xgstyle=y3&xmtype=options&if=wan_1

200G DP-16QAM

X 2

400G DC DP-16QAM

100G

WL3

100G

WL2

10G

eD

CO

Two regular 200G wavelengths separated by 50GHz grid

By closing down the gap between the 2 channels, it becomes a 400G Super-channel

2.7 km link Dispersion 82.5 ps Stability observed over >120 hours More than 48,301,908,336,000,000 of bits (or 6 Pbytes) flowed through this specific WAN link during that time! Not a single bit was lost in the process not even when we re-tuned the wavelengths into a SuperChannel.

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• Live Comcast Traffic over a single 1Tb/s SuperChannel wavelength

• 5x16QAM 200GHz SuperChannel, operating on a next gen line system comprised of smart Raman, programmable EDFA & flexible grid ROADM

• 1Tb/s, 200GHz SuperChannel operates alongside 10G, 40G, and 100G wavelengths running production traffic

• 10 spans, eLEAF fiber, ~ 1000 km !

Ashburn (Washington, DC) Charlotte

100GE

Router

100GE

Terabit SuperChannel Flexible grid ROADM

Colorless Filters

Router

1Tbps

10 Spans ~1000kms eLEAF 1st Deployment of Next

Generation Hybrid Raman Line System Live 10G/40G/100G (1Tb/s)

Traffic

1Tb/s

Terabit SuperChannel Flexible grid ROADM

Colorless Filters

1Tb/s

FEC Error Floors Bit Error Floor

Turbo Code 10-6 to 10-8

Most LDPC 10-8 to 10-10

Code and Algorithm

Design

Trapping Sets, Girth, or Implementation Problems

Eb/No (Input signal to noise ratio)

BER