New challenges for 40G and 100G Networks The Path to 100G New challenges for 40G and 100G Networks Arthur Moll BDM T&D EMEA Braodband Technology Event Rotterdam, November 10th, 2009

2 Why is 40G - 100G introduction so difficult?  We are reaching the limits of the physics  Limits of the optical fiber  Limits of the optics  Traditional technologies (NRZ, DWDM, EDFAs, ROADMs, etc) have issues at 100G  Old Rule of Thumb 4xData Rate = 2,5xCosts  Still valid forSTM-16 to STM-64  Not valid STM-64 to STM-256 (4xData = 5x Costs)  Mapping of 1GigE and 10GigE is difficult  E.g. 10GigE with GFP in OTU2 muxed in OTU3

3 From 10 G to 40G or 100G – Fiber Limit  CD Limit: 16 x less (120x)  PMD Limit: 4 x less (11x)  2 nd order PMD can not be neglected anymore  Makes some current network structure un-usable T STM-64T= 100 ps STM-256T= 25 ps OTU-4T= 8ps

4 From 10 G to 40G or 100G – Optic Limit 10Gbps 40Gbps 100Gbps???  Faster Modulation = Broader Spectrum - FWHM Spec meaningless!  Broader Spectrum ->Peak Power is not the answer -> Integrated Power  OSNR needs to be defined&measured differently  Curve shape needs to be considered.  Can we still do WDM?  Risk of Cross-Talk.

5 “Standard” OSNR measurement method IEC

6 For filtered signals (ROADMs), Interpolation method under-estimates the noise level as noise is « carved » with the signal by the filter Different paths have different Noise Contribution Real noise Interpolated noise OSNR measurement method Special case of filtered signals

7 EXFO Innovative In-band OSNR method Polarization diversity method Theory: Signal is polarized and noise is depolarized EXFO OSA have a polarization controller and polarization beam splitter at the input, allowing automated In-band OSNR measurement Noise In-band Noise In-band Signal OSNR Power vs polarization P peak P Noise

8 What are conditions for usable 100G System? Conditions for usable 100G Line Side Transmision-System:  More tolerant against CD&PMD  Fit into WDM Grid – 100GHz, but 50GHz is better  Co-operate with existing 10G/40G channels  Compatible with EDFAs and ROADMs  High OSNR  High Rx Sensitivity  Low EDFA Noise The answer: New Transmission System with new Modulation format

9 NRZ/RZ Intensity modulation NRZ-OOK (On/Off Keying) vs. RZ-OOK (On/Off Keying) NRZ-OOK RZ-OOK The intensity modulation is easily detected by direct detection with a photo detector Rx

10 Phase Modulation: DPSK DPSK (Differential Phase Shift Keying): A logical « 1 » and a « 0 » have light A « 1 » is represented by a phase shift by  

11 QPSK/DQPSK modulation 4 phases  2 bits/symbol QPSKDQPSK Phase Modulation: QPSK-DQPSK

12 PolMuxed – Phase Modulation: DP-QPSK DP-QPSK Modulation Two independent Data Streams Multiplexed with Polarization To achieve 112 Gbit/s typical with 28 Gbaud PM-(D)QPSK Very complex, cost intensive, but really robust!

13 Performance Overview Ref: Can 100Gb/s wavelengths be deployed using 10Gb/s engineering rules? StrataLight Communications Inc, Cisco Systems Inc

14 DP-QPSK Testing – Constellation Analyser Confidential

15 IEEE 802.3ba Pluggable Modules  CFP form factor package (86x127x14 mm / 3.4”x5.0”x0.55”)  100 GbE, 40 km on SMF (4x 25G LAN WDM, centered at 1305nm)  100 GbE, 10 km on SMF (4x 25G LAN WDM, centered at 1305nm)  40 GbE, 10 km on SMF (4x 10G CWDM, centered at 1305nm)  100 GbE, 10 km on SMF (10x 10G CWDM, centered at 1550nm)  From Santur Corporation  100 GbE, 100 m on MMF (850 nm parallel optics, 10x 10G)  CXP form factor (approx 20x54x11 mm / 0.78”x2.13”x0.43”)  100 GbE, 100 m on MMF (850 nm parallel optics, 10x 10G)  100 GbE, 10 m on active cable  QSFP form factor (18.4x72x8.5 mm / 0.72”x2.8”x0.33”)  40 GbE, 100m on MMF (850 nm parallel optics, 4x 10G)  40 GbE, 10 m on active cable CONFIDENTIAL

16 #5#5 #6#6 #8#8 #9#9 #7#7 #0#0 #1#1 #3#3 #4#4 #2#2 Mux/Demux in PCS Lanes Mux/Demux Mux/Demux (2:5  5:10) GbE serial bit stream Each PCS Lane is 5G bit stream Mux/Demux (2:5  5:10) b bits aka: CFP MAC & PHY

Implications? What needs to be tested?  148 Mio packets/s or 3xDVDs per sec  BERT of complete link  BERT per PCS Lane  PCS Lane concept is complex and has trouble zone  PCS Lane Marker (Order, Mapping)  Lane Skew  Mapping 10x10G elec. into 4x 25G bring new challenges  Ethernet Parameter (standard)  Frame Size distribution, Errors (FCS, Runt)  ThruPut, Frame Loss Skew= Propagation Difference, Bit delay, Offset

18 FTB-85100G – First portable 100G Tester BERT  On physical lane, PCS Lane or trunk PCS Error injection and monitoring  Bit error in Physical Lane or in PCS Lane  Invalid 64b/66b or unsupported PCS code  Invalid or duplicate PCS Lane markers PCS Lanes  Monitors lane marker period and reports any changes to PCS lane table  User defined or random mapping supported PCS Lane Skew  Dynamically change and measure PCS lane skew Ethernet & IP Testing  Layer 1 error/alarm injection and monitoring Packet Definition  User defined rate utilization  User defined MAC and IP address  User defined packet size up to 16k Error injection and monitor Layer 2  Payload and FCS Ethernet statistics  Jabber, giant, runt, oversize, FCS, total frames IP statistics  Multicast, broadcast, unicast, total Actual bandwidth usage statistics CONFIDENTIAL

G – Interface Specifications Client Interfaces  Very high CFP connector insertion rating  100G CFP, 100G CXP, 40G CFP, 40G QSFP Clocking  Stratum-3e clock with +/- 115 ppm user controllable offset  Support 100G /112G and 40G/43G rates OTU3 and OTU4 hardware ready  Unframed BERT (PRBS) at OTN rate  Framed OTN with parallel optics support on roadmap Pluggable interface controls & monitoring  Detailed CFP interface control  Control: laser on/off & amplitude (per lane)  Monitoring: Input level (per lane), Rx frequency CONFIDENTIAL

Questions?