Benn Thomsen. Microsoft Research

Transcription

1 Benn Thomsen Microsoft Research

2 Operating Optics at scale Data Center 1 km radius 150,000 servers 120, G optical transceivers Regional Network 70km radius 512 fibre pairs 2Pb/s WAN Data centers in 50+ regions More than 70,000km of fibre

3 Operating vertically: The rack Flops Bytes

4 Operating vertically: DC Network

5 Innovating vertically: Regional Architecture Distributed data centers across an 80Km region to keep pace with cloud growth Mega Data Center data centers in a region 5

6 Innovating in optics WAN Regional hub Colored optics Regional network (80 km links) Gray optics Mega data center Regional architecture 6

7 L2/3 switch 36xQSFP Linecard Mux/Demux Regional architecture: PAM4 QSFP28 DWDM transceiver» Dual-λ, 28 Gbaud PAM4» < 4.5 W per module ColorZ: Inphi 100G QSFP28 QSFP28 QSFP28 QSFP28 QSFP28 x4 TDCM QSFP28 EDFA VOA» Variable gain/tilt EDFAs» Automatic Tunable CD compensation QSFP28... x36 QSFP28 EDFA fiber span Optimised for 80km QSFP28 ADVA SmartAmp DCF

8 GB/$ IOPS/$ FLOPS/$ Gbps/$ Gbps/$ Disruption across the board CPUs Networking 1980s 2006 Data center network WAN capacity Time Time Time Storage Hard disk capacity Flash capacity Time Time

9 Tbps (log scale) $ Moore s Law for Networking Cloud network cost ~2x every two years Time Time

10 Throughput (Gb/s) Will free scaling continue? 2 bits/sym Tbps (Broadcom, Innovium) 256x 50Gb/s PAM4 6.4Tbps 256x 25Gb/s NRZ 256 1bit/sym Year Switches are becoming edge bandwidth limited

11 Tbps (log scale) $ Gbps/$ Moore s Law for Networking Data center network ~2x every two years Cloud network cost Time Time 11

12 Opportunity for photonics (shorter-term) Switch ASIC Optics ASIC Optics Fiber CMOS Scaling limit Multiple ASICs Today 16nm CMOS Fiber PCB Fiber PCB PCB On board optics In package optics Optical Network on chip

13 In-package optics (IPO) Tx/Rx Optical Source TX/RX Tx/Rx Switch ASIC Tx/Rx 64 1 Transceivers Chip 70mm Challenges Material: Silicon, InP Approach: Direct modulation, MZM, Ring modulator, Coherent?? Real estate, yield, operating environment Fibre attach PCB

14 Opportunity for photonics (long-term) Optical packet switch Fundamental challenges All optical header processing Optical buffers Optical circuit/burst switch More developed technology Higher- radix enables a flat network

15 Scale of solution An old idea made new Data center scale Network community Mechanically-moved mirrors (MEMS) New goalpost Large Scale data-center-wide & Fast switching Sub nano-second Optics community Chip scale Optical switch Slow (ms) Switching speed Fast (ns)

16 Bridging the last mile Apps Network Stack NIC PHY New applications that exploit the network properties e.g. low latency Network wide synchronisation Needs to support Burst mode CDR Optical Circuit Switch Apps Network Stack NIC PHY We need to consider the implications for the whole system

17 Optical Network Prototype Nanosecond-granularity switching Long, long way to go! 17

18 Integrated Photonics: 56 Gbaud Modulator Array 2x 56G Ring Modulator 4x 56Gbaud Modulators Output Fibre Attach 5mm

19 Chip testing

20 Storage Hot Online Technology: SSD, HDD $$$$$ Cool Read Write Occasionally Technology: HDD $$$ Cold Write Once, Read Once in a Blue Moon Technology: Tape, Blu-ray, Optical? $

21 GB/$ Today s cold storage Hard disk drive Tape Hard disk capacity Credit: stock.adobe.com

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23 Writing in Silica glass 23

24 Voxel structure d n 1 n 2 θ γ Transverse view Approx. ellipsoidal shape, γ~1μm, d~5um Volumetric nanograting Exhibits form birefringence Multi-level encoding using Ret and θ to store multiple bits per voxel

25 Voxel Writing Arrays of voxels Information encoded by modulating the intensity and polarisation of the laser pulses Challenge: Scaling write speed Modulator bandwidth Parallelism

26 Reading from Silica glass Sample Optical microscopy: Exploit developments in consumer cameras e.g. Sony 16MPixel 1000fps

27 Voxel Reading Read demo

28 A big opportunity cross-disciplinary approach Hardware Optics Storage Networking 28

29 Optics for the Cloud Application Network Storage New scenarios New hardware/software New Media Prototype switch Physical New optics Custom PIC Innovation across the cloud stack At Microsoft and with collaborators Silica

30 Want to know more