Considerations for 25Gb John D Ambrosia, Dell Jon Lewis, Dell Kapil hrikhande, Dell I 802.3 25Gb tudy Group I 802.3 ept 2014 Interim Kanata, Canada
thernet is volving Changing environment 10x the Performance @ 3x the cost The thernet of verywhere being used everywhere for everything Pick one Web cale Data Center, nterprise Data Center,, nterprise, Campus, Client ide Connections, tc Architectures Top-of-ack, nd-of-ow, Middle-of-ow I 802.3 thernet Bandwidth Assessment 32% to 95% CAG Connections from 0m to 40km Fixed Ports really? Form factor yes Function - no Market Timings Po Certification discussions Per the 25Gb CFI Consensus Presentation: Web-scale data centers and cloud based services need ervers with >10Gb capability Cost sensitive for nearer-term deployment emember that thernet products designed for this space will move into other applications! 2 I 802.3 25Gb tudy Group ept 2014 Interim, Kanata, Canada
Things to Consider for Objectives Cu Cable each Need for an MMF Objective? Need for electrical interfaces? 3 I 802.3 25Gb tudy Group ept 2014 Interim, Kanata, Canada
A Few Words First Lane ate / Maximizing witch fficiency / Breakout to lower rates driving new issues xamples uccess of 40Gb or 10Gb? Breakout from QFP has been a noted success. Challenges in quantifying application volumes Fixed Ports Form factor yes, Media / ate no On-going debate in I P802.3bs 400Gb in relation to 100Gb breakout Formation of I 802.3 25Gb tudy Group From 25Gb Consensus Presentation 25Gb/s technology standardized, developed, productized for 100Gb can be leveraged now! 4 I 802.3 25Gb tudy Group ept 2014 Interim, Kanata, Canada
Technology Nomenclature Description tatus Backplanes 100GBA-K4 100GBA-KP4 4 x 25 Gb/s (NZ) 4 x 25 Gb/s (PAM-4) I td 802.3bj TM -2014 atified Cu Twin-Axial 100GBA-C4 4 x 25 Gb/s Chip-to-Chip CAUI-4 4 x 25 Gb/s I P802.3bm in ponsor Chip-to-Interface CAUI-4 4 x 25 Gb/s Ballot Module Form Factor FP28 1 x 28 Gb/s ummary Document FF-8402 QFP28 4 x 25 Gb/s tyle 1 - MDI for 100GBA- C4 ummary Document FF-8665 CFP2 4 x 25 Gb/s CFP4 4 x 25 Gb/s tyle 2 MDI for 100GBA-C4 5 I 802.3 25Gb tudy Group ept 2014 Interim, Kanata, Canada
6 I 802.3 25Gb tudy Group ept 2014 Interim, Kanata, Canada
Big Driver: Total Cost of Ownership epresents 100% port utilization and no stranded ports 7 I 802.3 25Gb tudy Group ept 2014 Interim, Kanata, Canada
Cu Cable Distribution Intra-rack 3m general agreement To witch Data obtained from Two product groups within Dell (past 1 to 1.5 years) 10Gb based products (servers & switches) 40Gb based products (servers & switches) Total (Cu Division A Division B Cable) <=3m 79% 63% 5m 21% 28% >5m 0% 8% Data obtained from Two cabling companies (Molex,Tyco) Total (Cu Company A Company B Cable) MDI1/MDI2 <=3m 62% / 69% 80% 5m 30% / 24% 15% >5m (Passive) 1% 5% >7m (Active) 7% / 6% - Inter-rack 5m 8 I 802.3 25Gb tudy Group general agreement ept 2014 Interim, Kanata, Canada
Thoughts elated to Cu Cable Objective FP28 FP28 FP28 FP28 FP28 server FP28 QFP28 switch Lower Density Applications Higher Density Applications Different applications easy to envision Lower density based on 25Gb / FP28 from server to switch Higher density based on breakout from 100GBA-C4 / QFP28 on switch to FP28 on server Channel budget? witch must be constrained to meet 100GBA-C4 budget erver different options Different server port types to support budget for lower / higher density switch applications? Add budget to server from cable? educed budget for server NIC, 3m no FC? 9 I 802.3 25Gb tudy Group ept 2014 Interim, Kanata, Canada
Beyond Top of ack To witch I/O per 10G erver** ports To Mo Mo o FP+ (PHY Type) Optics 31.5% C (all passive, no active cables) Unknown* ome portion of 68.5% ome portion of 68.5% - in some instances dual ports are used for physical redundancy, but one port may not be populated ** - data gathered from Dell general purpose server family 3m Cu 5m Cu Active Cables or MMF 10 I 802.3 25Gb tudy Group ept 2014 Interim, Kanata, Canada
Comparison Between Options Option #1 educe cable reach to 3m / assign budget to server High density passive Cu switching applications limited to intra-rack / higher density server form factors Potential for stranded ports on high density switches increases More switches CAPX / OPX Forces use of active cable assemblies / optics for reaches beyond 3m Limits broad market potential to intra-rack applications Option #2 Choose 5m reach objective and TF can specify 3m cable with no FC Asymmetrical budget, NIC needs less loss than budgeted for host. Leave switch budget alone, 3m cable. No FC educes latency (for those applications) Option #3 Choose objective targeting 3m intra-rack applications Choose objective targeting 5m inter-rack applications 11 I 802.3 25Gb tudy Group ept 2014 Interim, Kanata, Canada
Chip-to-Module (C2M) Interfaces Chip-to-module (C2M) interfaces will happen FP28 for 25Gb connections anticipated QFP28 for 4x25 Gb connections anticipated ecommend FP28 / QFP28 for MDI C2M channel budget details need to be consolidated with host trace portion of Cu cable channel budget Chip-to-chip interface should be defined Leverage I 802.3bm work ecommend adopting objectives for chip-to-chip and chip-to-module electrical interfaces 12 I 802.3 25Gb tudy Group ept 2014 Interim, Kanata, Canada
ummary ecommendations Adopt a Cu cable objective for a 5m reach only (inter-rack) Adopt a Cu cable objective for a 3m reach only (intra-rack) Adopt a MMF Objective targeting xx m Data on reach not available at this time Consider FP28 / QFP28 for 25Gb MDIs Adopt objectives for chip-to-chip and chip-to-module electrical interfaces 13 I 802.3 25Gb tudy Group ept 2014 Interim, Kanata, Canada