Fiber Technology Trends for Next Generation Networks
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This document summarizes Christopher Towery's presentation on optical networking technologies towards achieving terabit per second capacities. The presentation discusses recent experiments that have extended transmission distances and capacities. It also covers topics like quasi-single mode fibers, submarine network evolution, extending terrestrial networks through challenging terrain, and extending reach in legacy networks. Experimental results are presented to demonstrate technologies for high capacity transmission over long distances.
![Optical Fiber 7
.
© 2015 Corning Incorporated .
.
Using more modes to get higher capacity
2 related approaches
7
• Few-mode fibers are considered for mode-multiplexed transmission with
MIMO receivers
• Requires major transformation of the optical communication infrastructure
• Benefits of the parallelism brought by MDM is not well established
• Signal processing complexity is significant, and scales with transmission distance
[1] F. Yaman et al., Opt. Express, 18, 21342-21349 (2010).
[2] J. D. Downie et al, Opt. Express, 19, B363-B369 (2011).
[3] Q. Sui et al, Opt. Express, 23, 3156-3169 (2015).
• Few-mode fibers can be used for Quasi-single mode (QSM) transmission:
• FMFs can be used for the benefit of their larger effective area.
• FMFs can be incorporated into the existing single-mode infrastructure if signal is transmitted only in the
fundamental mode.
• QSM suffers from multi-path interference (MPI). However, MPI can be mitigated with DSP.](https://image.slidesharecdn.com/cpqdcorningmay2015draftmododecompatibilidade-150616175416-lva1-app6892/85/Fiber-Technology-Trends-for-Next-Generation-Networks-7-320.jpg)
![Optical Fiber 9
.
© 2015 Corning Incorporated .
.
Quasi-single mode transmission with hybrid spans
9
FMF
Splice Splice
SM-EDFA SM-EDFA
Low DMA
High DMA
Single-mode fiber
[1] F. Yaman et al., Proc. OFC’13, paper OTu1D.2 (2012).
[2] Q. Sui et al, Opt. Express, 23, 3156-3169 (2015).
[2]
Power
Span Length
Splice
MPI
Span Length
[1]
DMA:= Differential modal attenuation](https://image.slidesharecdn.com/cpqdcorningmay2015draftmododecompatibilidade-150616175416-lva1-app6892/85/Fiber-Technology-Trends-for-Next-Generation-Networks-9-320.jpg)
Fiber Technology Trends for Next Generation Networks
- 1. Christopher Towery Corning Optical Communications May 28th 2015 towerycr@corning.com IV Towards Terabit per Second Optical Networking International Workshop on Trends in Optical Technologies
- 2. Optical Fiber 2 . © 2015 Corning Incorporated . . Outline • Hero Experiments and Technology Trends • Quasi-Single Mode Fibers • Submarine Network Evolution • Un-repeatered and long span terrestrial applications – Extending the network through challenging terrain • Extending systems reach in a legacy network
- 3. Optical Fiber 3 . © 2015 Corning Incorporated . . Capacity-distance reach shows signs of consistent growth, however, no new records were set (534 Pb/s x km is still max.) SDM = Multi-core fibers + Few-mode fibers OFC 2015
- 4. Optical Fiber 4 . © 2015 Corning Incorporated . . No records observed in total capacity either in SMF or SDM (FMF and MCF) fibers • Appetite for hero SDM transmission experiments seems to be fading (see red points)… • …But there was an increased number of results related to components and fiber designs to enable SDM transmission (not reflected in the graph) OFC 2015
- 5. Optical Fiber 5 . © 2015 Corning Incorporated . . What are the CDN’s saying about submarine networks? -- More capacity…..
- 6. Optical Fiber 6 . © 2015 Corning Incorporated . . CDNs could be very large, their backbone is global, resembles submarine network with “long, big pipes” ~10,000 km ~5,000 km ~5,000 km V. Kamalov et. al. ECOC 2014
- 7. Optical Fiber 7 . © 2015 Corning Incorporated . . Using more modes to get higher capacity 2 related approaches 7 • Few-mode fibers are considered for mode-multiplexed transmission with MIMO receivers • Requires major transformation of the optical communication infrastructure • Benefits of the parallelism brought by MDM is not well established • Signal processing complexity is significant, and scales with transmission distance [1] F. Yaman et al., Opt. Express, 18, 21342-21349 (2010). [2] J. D. Downie et al, Opt. Express, 19, B363-B369 (2011). [3] Q. Sui et al, Opt. Express, 23, 3156-3169 (2015). • Few-mode fibers can be used for Quasi-single mode (QSM) transmission: • FMFs can be used for the benefit of their larger effective area. • FMFs can be incorporated into the existing single-mode infrastructure if signal is transmitted only in the fundamental mode. • QSM suffers from multi-path interference (MPI). However, MPI can be mitigated with DSP.
- 8. Optical Fiber 8 . © 2015 Corning Incorporated . . • In traditional single-mode fibers the light propagates in the fundamental mode, which is the only mode supported in the fiber • In quasi-single mode fibers, the light is “forced” on a fundamental mode Tx Rx Tx Rx How does a Quasi-Single Mode Fiber work?
- 9. Optical Fiber 9 . © 2015 Corning Incorporated . . Quasi-single mode transmission with hybrid spans 9 FMF Splice Splice SM-EDFA SM-EDFA Low DMA High DMA Single-mode fiber [1] F. Yaman et al., Proc. OFC’13, paper OTu1D.2 (2012). [2] Q. Sui et al, Opt. Express, 23, 3156-3169 (2015). [2] Power Span Length Splice MPI Span Length [1] DMA:= Differential modal attenuation
- 10. Optical Fiber 10 . © 2015 Corning Incorporated . . Technology – Ultra-Large Aeff OFC 2015 post-deadline paper demonstrates record SE over Trans-Atlantic distance using Quasi-SMF fiber
- 11. Optical Fiber 11 . © 2015 Corning Incorporated . . Hybrid Spans 11 Fiber Length (km) Atten (dB/km) Loss (dB) Span1 102.82 16.5 FMF 51.15 0.154 Vascade® EX3000 51.67 0.149 Span2 101.75 17 FMF 51.4 0.16 EX3000 50.35 0.157 Span3 100.01 16 FMF 51.4 0.156 EX3000 48.61 0.156 Span4 102.17 16.7 FMF 51.15 0.16 EX3000 51.02 0.154 Span5 101.43 16.2 FMF 51.4 0.156 EX3000 50.03 0.153 x5 FMF Vascade® EX3000Bridge Fiber Parameters FMF Vascade® EX3000 Effective Area ~200 µm2 150 µm2 Supported Modes LP01, LP11 Diff. Modal Attenuation 0.3-0.5 dB/km Diff. Modal Group Delay ~0.93 ns/km • Vascade® EX3000 is used as bridge fiber between FMF and amplifier pigtail. • Tapered splicing is used between all splice points between dissimilar fibers • Average loss from the total of 4 splices and two connectors are 0.7 dB.
- 12. Optical Fiber 12 . © 2015 Corning Incorporated . . -20 -15 -10 -5 0 5 10 15 20 -35 -30 -25 -20 -15 -10 -5 0 Time (ns) |H11 |2 (dB) All-single-mode fiber All-few-mode fiber Hybrid All-SMF vs ALL-FMF vs Hybrid spans Hybrid has less MPI All-Single-Mode Fiber Loop All-Few-Mode Fiber Loop Hybrid span Loop 16 17 18 19 20 21 22 23 24 25 26 27 2 3 4 5 6 7 8 9 Received OSNR @ 0.1 nm (dB) Q(dB) 4060 km All-single-mode-fiber 16 17 18 19 20 21 22 23 24 25 26 27 2 3 4 5 6 7 8 9 Received OSNR @ 0.1 nm (dB) Q(dB) 4060 km All-single-mode-fiber All-few-mode fiber 1 dBMPI 16 17 18 19 20 21 22 23 24 25 26 27 2 3 4 5 6 7 8 9 Received OSNR @ 0.1 nm (dB) Q(dB) 4060 km All-single-mode-fiber All-few-mode fiber Hybrid 16 17 18 19 20 21 22 23 24 25 26 27 2 3 4 5 6 7 8 9 Received OSNR @ 0.1 nm (dB) Q(dB) 4060 km 2030 km All-single-mode-fiber All-few-mode fiber Hybrid MPI_FMF -10.88 dB MPI_Hybrid -14.69 dB
- 13. Optical Fiber 13 . © 2015 Corning Incorporated . . Paths to higher submarine cable capacity Paths to Higher Capacity More λ’s in C band C+L band EDFA Use >8 FPs in the repeater Vascade EX2000 Vascade EX3000 50 km 80 km 50 km 80 km 80 λ’s 15.5 17.1 16.3 17.9 100 λ’s 16.5 18.1 17.3 18.9 150 λ’s 18.2 19.8 19 20.6 • Only small additional power is needed (rel. to current 17-19 dBm) • No change in design • Possible to support 300 λs for C+L band transmission • May require re- designed repeaters • May need more/re- design power feed equipment • Use of all 8 FPs is supported by an original design • No change in design Use all 8 FPs in the repeater • May require more repeaters or re- designed repeaters • Requires more copper to reduce resistance; more expensive cable Will likely be developed in parallel
- 14. Optical Fiber 14 . © 2015 Corning Incorporated . . Challenge Objective Expanding Terrestrial Backbone Networks Two scenarios operators are facing today Greenfield Building fiber where it isn’t available today Difficult environments Legacy Meeting increased demand Aging infrastructure Cost (CapEx, OpEx), Reliability, Speed to Rollout, Complexity,…..
- 15. Optical Fiber 15 . © 2015 Corning Incorporated . . The carriers that are building greenfield long haul networks are doing so for various reasons Routing Diversity Access to new markets Support for national broadband plans Backhaul for wireless build-outs
- 16. Optical Fiber 16 . © 2015 Corning Incorporated . . Greenfield long haul builds are also often driven by non-telco operators, a few examples DefenseOil and Gas Science Border SecurityElectric Utilities
- 17. Optical Fiber 17 . © 2015 Corning Incorporated . . Many of the new long haul builds are going through challenging terrain
- 18. Optical Fiber 18 . © 2015 Corning Incorporated . . Locating and powering remote amplifier or repeater sites can be problematic Sites require power for equipment and cooling Many may not even be accessible 365days a year
- 19. Optical Fiber 19 . © 2015 Corning Incorporated . . How much can an intermediate amplifier site cost? Amplifier Site Requirement Estimated Costs (low) Estimated Costs (high) Site construction costs (acquisition, preparations, security, etc.) $100k $250k+ Controlled Environment Vault (CEV) $30k $150k AC Power Construction ($22k/km) $10k $500k DC Power Back-up (Batteries, Fuel Cells, Generator, etc.) $150k $300k OPEX ( Fuel, Service, Labor, Road Access, Site Maintenance, Security etc.) $36k/year $200k/year Total of first year costs $326k $1.4M Additionally, reliability and accessibility can be issues in some regions
- 20. Optical Fiber 20 . © 2015 Corning Incorporated . . Minimizing intermediate amplifier or regenerator sites can be a key consideration Example: China’s State Grid Project through the Himalayas • Average Elevation 5,000m, temperatures as low as -55C • Span distances > 300km One very long span Or several long spans Example: TIM Brasil through Amazon region • Over 2000km of OPGW • 13 Spans longer 100km, 5 Spans longer than 200km
- 21. Optical Fiber 21 . © 2015 Corning Incorporated . . Technologies are enabling more robust and flexible network design, and reducing the need for intermediate amplifier sites Better Electronics Modulation and FEC Increase in optical link length adopting next generation FEC 1st gen FEC 2nd gen FEC 2nd gen FEC 3rd gen FEC 3rd gen FEC 4th? gen FEC Coherent Detection Advanced Amplification EDFA High Power EDFA + Counter Propagating Raman + Co-Propagating Raman + ROPA + Dual ROPA Ultra Low Attenuation and Large Aeff Fibers “Low-Loss” “Ultra-Low-Loss” “Ultra-Low-Loss” + Large Aeff
- 22. Optical Fiber 22 . © 2015 Corning Incorporated . . 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 0.15 0.155 0.16 0.165 0.17 0.175 0.18 CummulativeProbablity(%) Attenuation at 1550 nm (dB/km) Cable Fiber Post dead-line paper at OFC 2014 makes use of coherent detection, Raman amplification and advanced fiber to set new 100G distance record • Cable: 8.3 km Altos loose tube 204 cable on a 0.9m diameter spool • Optical Fiber: Vascade EX2000 with Aeff=112 µm2 – Median attenuation improved after cabling from 0.161 dB/km to 0.159 dB/km, max attenuation 0.173 dB/km • Span: 556.7 km, total loss 90.2 dB, spliced attenuation 0.162 dB/km Source: Xia, Chang, Ten, et al OFC 2014 Th5A.7
- 23. Optical Fiber 23 . © 2015 Corning Incorporated . . Trial set-up: Utilized Dual Raman and ROPA 100G MXP λ1 100G MXP λ2 100G MXP λ3 100G MXP λ4 WSS DCU EOA 289.3 km or 255.8 kmROPA (F) 133.7 km EOA ROPA (B) Residual pump sharing WSS Forward Raman Backward Raman 100G MXP λ1 100G MXP λ2 100G MXP λ3 100G MXP λ4 (a) ROPA (B) ROPA (F) p P’ 133.7 km 556.7 km for 1 x 100G transmission and 523 km for 4 x 100G transmission Passive repeater Source: Xia, Chang, Ten, et al OFC 2014 Th5A.7 Vascade® EX2000 fiber
- 24. Optical Fiber 24 . © 2015 Corning Incorporated . . We have demonstrated two record results at OFC 2015 with two external partners: ASN and Xtera
- 25. Optical Fiber 25 . © 2015 Corning Incorporated . . Challenge Objective Expanding Backbone Networks Two scenarios operators are facing today Greenfield Building fiber where it isn’t available today Difficult environments Legacy Meeting increased demand Aging infrastructure Cost (CapEx, OpEx), Reliability, Speed to Rollout, Complexity,…..
- 26. Optical Fiber 26 . © 2015 Corning Incorporated . . We have recently investigated maximum reach and achievable capacity over a DT network when using three types of fibers • Transparent network (no intermediate regeneration) • 504km is the maximum distance between two adjacent cities
- 27. Optical Fiber 27 . © 2015 Corning Incorporated . . Fiber rankings in terms of transmission reach: 1) Vascade® EX2000; 2) SMF-28® ULL; 3) Legacy fiber • System parameters: – EDFA noise figure: 5dB – Span length: 80km – WDM channels: 150 – Cable drum length: 4km – Splice loss: 0.05 dB – 32Gbaud (6.25dB FEC threshold) – Polarization multiplexing – End-of-life cable margin: 3dB/100km – Additional Q margin: 3dB Legacy fiber Corning® SMF-28® ULL Corning® Vascade® EX2000 Attenuation (dB/km) 0.25 0.165 0.159 Aeff (µm2) 82 82 112 n2 (m2/W) 2.3 x 10-20 2.1 x 10-20 2.1 x 10-20 Dispersion (ps/nm/km) 17 17 20.3 Gaussian noise analytical model; implementation penalty neglected
- 28. Optical Fiber 28 . © 2015 Corning Incorporated . . Legacy fiber Extra reach enabled by SMF-28 ULL fiber Legacy fiber can support 24% of routes at 200G SMF-28 ULL covers 96% of routes; Vascade EX2000 covers all Transparent networks make the distribution of distances wider – SMF-28 ULL fiber covers 96% of links at 200G with 80km spans Extra reach enabled by Vascade EX2000 fiber
- 29. Optical Fiber 29 . © 2015 Corning Incorporated . . Building cost effectively as a large incumbent carrier – Things to think about Take advantage of existing duct Take advantage of lower-cost installation techniques Convergence Build as a Consortium
- 30. Thank you
- 31. Optical Fiber 31 . © 2015 Corning Incorporated . . • In traditional single-mode fibers the light propagates in the fundamental mode, which is the only mode supported in the fiber • In quasi-single mode fibers, the light is “forced” on a fundamental mode Tx Rx Tx Rx How does a Quasi-Single Mode Fiber work?
- 32. Optical Fiber 32 . © 2015 Corning Incorporated . . Roadmap for terrestrial system capacity growth: Smarter Networking, FEC and more Raman 2015 20252020 Raman Amplifiers 100G MSA 50/100/150/ 200G 50-200G; with finer tuning FEC Improvements Smart Networking The carriers are split on those who deploy 100G now, or wait until adaptive-rate transponders become available SE Reach(km) 50G 100G 200G 3 6 150G 1.5 4.5 SE Reach(km) 50G 100G 200G 3 6 150G 1.5 4.5
- 33. Optical Fiber 33 . © 2015 Corning Incorporated . . WW Long-Haul Market 90% of the New Long Haul Routes are being build outside North America and Europe Source: CRU ~90% of the LH market is in emerging regions
- 34. Optical Fiber 34 . © 2015 Corning Incorporated . . In 2009 traditional Telecoms started loosing their dominance as primary carriers of Internet traffic, CDNs gained share • CDNs became as influential as traditional carriers as telecom equipment buyers and defining technology direction 2009 University of Minnesota Atlas Observatory study
- 35. Optical Fiber 35 . © 2015 Corning Incorporated . . Adaptive modulation techniques optimize today’s wireless networks and tomorrow’s fiber networks The same concept is now being used in transmission over optical fiber – providing similar benefits Speed (Mb/s) Distance from cell tower (km)
- 36. Optical Fiber 36 . © 2015 Corning Incorporated . . Variable-rate transponder uses adaptive modulation to enable elastic optical networks Source: “Extending software defined network principles to include optical transport”, Verizon, IEEE Communications Magazine, March 2013 • 1 bit per symbol • 2 bits per symbol • 3 bits per symbol • 4 bits per symbol IncreasingSEandrequiredOSNR BPSK QPSK 8 QAM 16 QAM cHigher modulation density provides more bits per channel… …but shortens the reach
- 37. Optical Fiber 37 . © 2015 Corning Incorporated . . SMF-28® ULL and Vascade® EX2000 fibers also maximize achievable capacity for a given reach QPSK 8-QAM 16-QAMPM-BPSK 32-QAM 64-QAM Spectral efficiency, b/s/Hz Maximum reach, km Legacy fiber SMF-28® ULL fiber 50G Modulation: Bit-rate: 100G 150G 200G 250G 300G 50% Vascade® EX2000 fiber 100% Extra 50% 3x 30%