Optical interconnects in data centers Optical Communication Systems and Networks: From Data Centers to Broadband Access to Core Transport Networks 9 May 2014 Christoforos Kachris Athens Information Technology (AIT) email: kachris@ait.edu.gr
60-secs on the web C. Kachris, Athens Infromation Technology, May 2014 2
How Big are Data Centers Data Center Site Sq ft Facebook (Santa Clara) 86,000 Google (South Carolina) 200,000 HP (Atlanta) 200,000 IBM (Colorado) 300,000 Microsoft (Chicago) 700,000 [Source: How Clean is Your Cloud?, Greenpeace 2011] Wembley Stadium:172,000 square ft C. Kachris, Athens Infromation Technology, May 2014 3
Data Center Traffic In 2014, 77% of traffic remained within the data center, and this will decline only slightly to 76 percent by 2015 C. Kachris, Athens Infromation Technology, May 2014 4
Data Centers Power Consumption Data centers consumed 330 Billion KWh in 2007 and is expected to reach 1012 Billion KWh in 2020 2007 (Billion KWh) 2020 (Billion KWh) Data Centers 330 1012 Telecoms 293 951 Total Cloud 623 1963 [Source: How Clean is Your Data Center, Greenpeace, 2012 C. Kachris, Athens Infromation Technology, May 2014 5
Power consumption of Data Centers The cost to power and cool the data centers will reach the CAPEX cost Data center networks (DCN) consume as much as 23% of the total power consumption Data center servers consume as much as 40% of the total power consumption in a Data Center [Source: Where does power go?, www.greendataproject.org] C. Kachris, Athens Infromation Technology, May 2014 6
Data Center Networks Data Center Content switches & Load balance ToR switches Servers Core switches Aggregate Switches Rack Internet 10 Gbps 10 Gbps Rack Rack Rack The Data Center Networks are usually based on a fat-tree topology using commodity switches Core Layer: Used to interconnect the access switches (10Gbps) Aggregate Layer: Used to interconnect the ToR switches (10Gbps) Rack Layer: Top-of-Rack (ToR) switches are used to connects the servers in a rack (1Gbps) C. Kachris, Athens Infromation Technology, May 2014 7
Data Center Networks Data Center Content switches & Load balance Internet Telecommunication network follow a similar approach: Core network, Aggregation/Metro Network, Access network Core switches Aggregate Switches 10 Gbps ToR switches Servers 10 Gbps SERENDIPITY Rack Rack Rack Rack C. Kachris, Athens Infromation Technology, May 2014 8
Opaque to transparent networks [Source: C. Kachris, K. Kanonakis, I. Tomkos, Optical Interconnection Networks in Data Centers: recent trends and future challenges, Communication Magazine, 2014] C. Kachris, Athens Infromation Technology, May 2014 9
Opaque to transparent networks [Source: C. Kachris, K. Kanonakis, I. Tomkos, Optical Interconnection Networks in Data Centers: recent trends and future challenges, Communication Magazine, 2014] C. Kachris, Athens Infromation Technology, May 2014 10
How green is all-optical? Current switches consume a high amount of energy for the E/O, O/E, buffers and Switch Fabrics All-optical switches can eliminate the need for buffers, E/O and O/E converters C. Kachris, Athens Infromation Technology, May 2014 11
Need for All-optical Interconnects We need High bandwidth, Low latency, scalable, energy efficient Data Centers Networks that can sustain the exponential increase of the network traffic All-Optical Interconnects: No need for buffering Switching can be performed using passive components at the wavelength-level (e.g. splitters, wavelength switching - AWGR) Higher bandwidth (wavelength multiplexing) Lower latency Lower power consumption, footprint, carbon emissions C. Kachris, Athens Infromation Technology, May 2014 12
The optical toolbox Coupler AWGR Wavelength switching Optical MEMS Spatial switching C. Kachris, Athens Infromation Technology, May 2014 WSS Wavelength and spatial switching 13
All-optical interconnects in AIT In the WSS-based scheme each node consists of a rack that accommodates several servers and each rack uses a Top-of-the-Rack (ToR) switch to communicate with other racks. Each ToR switch has several optical transceivers (e.g. 1Gbps SFP) to connect to the servers and one or more optical transceivers Optical Switching Matrix WSS MUX Coupler WSS-based Optical Switching WSS-based Optical Switching λ1 λ2 λ3 λ8 λ1 λ2 λ3 λ8 λ1 λ2 λ3 λ8 ToR ToR ToR [C. Kachris, I. Tomkos, Optical -based Data Center Networks, OFC 2012] C. Kachris, Athens Infromation Technology, May 2014 14
All-optical interconnects in AIT Power reduction is achieved though the use of less number of transceivers but enhanced with for better spectral efficiency Optical Switching Matrix WSS MUX Coupler WSS-based Optical Switching WSS-based Optical Switching λ1 λ2 λ3 λ8 λ1 λ2 λ3 λ8 λ1 λ2 λ3 λ8 ToR ToR ToR C. Kachris, Athens Infromation Technology, May 2014 15
Potential Market All major internet service companies and niche market that need low latency interconnects C. Kachris, Athens Infromation Technology, May 2014 16
Market size of DCN The data center networking market currently stands at $12.49 billion and will grow at a compound annual rate of 11.8% during the next five year C. Kachris, Athens Infromation Technology, May 2014 17
Start-ups in optical interconnects Lightfleet ODM solves the big data dilemma for large data centers Compass-EOS is the first commercially available technology using optical chip-to-chip communication. C. Kachris, Athens Infromation Technology, May 2014 18
Conclusions Future Data Center Network will require high bandwidth, low latency, energy-efficient interconnects to face the traffic of cloud computing Optical Interconnects looks as a promising solution in providing high bandwidth, low latency and energy efficient interconnects Opportunity for innovative all-optical solutions/start-ups C. Kachris, Athens Infromation Technology, May 2014 19
Questions? C. Kachris, I. Tomkos A Survey on Optical Interconnects for Data Centers, IEEE Survey and Tutorials, 2012 C. Kachris, K. Bergman, I. Tomkos, Optical Interconnects for Future Data Center Networks, Springer Publication, end of 2012 Bibliography on optical interconnects for data centers www.ait.gr/ait_web_site/researcher/kachris/optical_interconnect_bibliography.htm Thank you! Christoforos Kachris kachris@ait.edu.gr C. Kachris, Athens Infromation Technology, May 2014 20
Backup slides C. Kachris, Athens Infromation Technology, May 2014 21
Every minute in Internet C. Kachris, Athens Infromation Technology, May 2014 22