Transcription
Fibre Channel SpeedmapLive WebcastApril 6, 201711:00 am PT
Today’s PresentersTony Bourke@tbourkedatacenteroverlords.comDave AlexanderJ Metz@ucs etz.com/
Agenda IntroductionsDiscuss differences in systems and networkingDiscuss product/interface namingDiscuss encoding and overheadDiscuss how to compare Fibre Channel and Ethernet speedsQ&A!
Bytes versus BitsSystem and storageadministrators seespeed as Bits/sBytes/sNetwork administratorssee speed as
Raw and PayloadSystem and storageadministrators seespeed as RawthroughputPayloadthroughputNetwork administratorssee speed as
Fibre Channel GoalWe care about Bytes per second For every 1 Gigabit of linkspeed, provide 100 MB/s ofpayload throughput1 Gigabit 100 MB/s
Speed Name Misnomers Product Name (link speed)– Just the name we call it. In both Ethernet and FC, they’re not accurate BAUD rate (how fast 1s/0s are running)– Doesn’t account for encoding (8b/10b, 64b/66b)– Doesn’t account for headers versus payload Throughput (how fast data runs through the link)– Raw throughput (payload headers)– Payload throughput (payload)Interface Name1GFC1 Gbit EthernetEncodingThroughputBaud (Gigabaud)8b/10b100 MB/s1.06258b/10b125 MB/s1.25
8b/10b Encoding For every 8 bits, 2 extra bits are sent– Balances the 1s and 0s– Clock recovery– Lose 20% to overhead10-bits8-bits2-bits
8b/10b Encoding StrategyFibre Channel 1 Gigabit speed, 1.0625 Gbaud rate 100 MB/s payload throughput No increase in speed to make upfor the overhead in 8b/10b encoding Slight increase in speed (6.25%) tomake up for headersProtocol1GFC1 Gbit EthernetEncodingEthernet 1 Gigabit speed, 1.25 Gbaud rate 20% increase in speed to make upfor the overhead in 8b/10b encoding No increase to make up for headers (1000 𝑀𝑏/𝑠 ) / 8 𝑏𝑖𝑡𝑠/𝑏𝑦𝑡𝑒 125𝑀𝐵/𝑠Transfer speedBaud (Gigabaud)8b/10b100 MB/s1.06258b/10b125 MB/s1.25
Payloads: Fibre Channel2112 bytes4 bytes 4 bytesData Field64 bytesOpXonalHeaders2048 bytesPayload(usually SCSI)2148 Bytes total MTUCRCFC Header4 bytes 24 bytesStart-of-FrameSCSIEnd-of-FrameHistorically Fibre Channelpayloads have been .
Payloads: EthernetHistorically Ethernetpayloads have been .IPEthernetTCP HTTPIPv4, IPv6, ICMP, FibreChannel (FCoE), HTTP, FTP,SNMP a variety
Payload Throughput versus RawPayload Throughput (FC)Raw Throughput (Network) Payload only Reasonable choice in mono-trafficenvironment Actual speed is increased slightly toaccommodate headers Payload Headers Reasonable choice when there aremultiple headers (TCP, IP, Ethernet) Reasonable choice when formultiple types of traffic (withdifferent header lengths) Reasonable choice when there arevariable length headers (HTTP,FTP, Layer 7)– We see this on switch backplanes,increasing speeds to accommodateinternal encapsulations such as HiGig2for Broadcom
Move to 64b/66b Encoding With 16GFC (and 10GFC), encoding moved to 64b/66b encoding– For every 64 bits, 66 bits are sent across the wire– Only 3.125% overhead instead of 20%, much more efficient The goal of providing 100 MB/s of payload throughput per“Gigabit” never changed in Fibre Channel 16GFC 1600 MB/s 14.025 Gbaud66-bits64-bits2-bits
Fibre Channel Speeds and FeedsProduct Name1 Gigabit2 Gigabit4 Gigabit8 Gigabit16 Gigabit32 Gigabit128 GigabitPayload Throughput100 MB/s200 MB/s400 MB/s800 MB/s1600 MB/s3200 MB/s12800 MB/s
Fibre Channel Speeds and FeedsProduct Name1GFC2GFC4GFC8GFC16GFC32GFC128GFCPayload Throughput‘100 MB/s200 MB/s400 MB/s800 MB/s1600 MB/s3200 MB/s12800 MB/sGBaud1.06252.1254.258.514.02528.05112.2With Fibre Channel, the key figure is(payload) throughput
Comparing Ethernet and Fibre ChannelProtocol1 Gbit FC1 Gbit Ethernet2 Gbit FC4 Gbit FC8 Gbit FC10 Gbit Ethernet16 Gbit FC32 Gbit FC40 Gbit Ethernet100 Gbit Ethernet128 Gbit /66b64b/66b64b/66b64b/66b64b/66nTransfer speedBaud (Gigabaud)100 MB/s125 MB/s200 MB/s400 MB/s800 MB/s1250 MB/s1600 MB/s3200 MB/s5000 MB/s12500 MB/s12800 03.125112.2
Comparing Ethernet and Fibre ChannelProduct NameEncodingThroughputGbaud8b/10b800 MB/s8.510 GigE64b/66b1250 MB/s10.312516GFC64b/66b1600 MB/s14.02525 GigE64b/66b3125 MB/s25.7812532GFC64b/66b3200 MB/s28.0540 GigE64b/66b5000 MB/s41.25100 GigE64b/66b12500 MB/s103.125128GFC64b/66b12800 MB/s112.28GFCCompare throughput to compare speedswith Ethernet and Fibre Channel
Conclusion Fibre channel and Ethernet discuss speeds differently– Historical reasons behind it To compare speed of Ethernet and Fibre Channel, look atthroughput rates Consider that throughput rates are payload (Fibre Channel) andraw (Ethernet)
Q&A
After this Webcast Please rate this event – we value your feedback We will post a Q&A blog at http://fibrechannel.org/ with answers toall the great questions we received today Follow us on Twitter @FCIAnews Join us for our next live FCIA webcast:Fibre Channel FundamentalsJune 15, 201711:00 am PTRegister at https://www.brighttalk.com/webcast/14967/255009
Thank you!
Fibre Channel 1 Gigabit speed, 1.0625 Gbaud rate 100 MB/s payload throughput No increase in speed to make up for the overhead in 8b/10b encoding Slight increase in speed (6.25%) to make up for headers Ethernet 1 Gigabit speed, 1.25 Gbaud rate 20% increase in speed to make up for the overhead in 8b/10b encoding
