SFP+ DAC VS Fiber Latency: Copper Is Faster Than Fiber

Tom here from Warren Systems we're going to talk about why copper is faster than fiber if you want learn more about my company head over to Lauren systems comm if you want to hire us there's a hires button at the top you fellows contact form or head or to forums at Lauren systems comm where we can continue the discussion and geek out about this this is neat so I you need video yesterday about fiber and sfp+ and ten gig connections and you know some of the adapters and I have those same adapters in front of me still but I said I didn't have the ability to really show latency differences between DAC versus fiber versus the UTP cable right here now the first one we're gonna throw out is this this is not because of latency reasons if we use the SFP module asipi plus or if it's directly built into the switch and you're doing UTP 10 gig it is greatly convenient just snap it in there's no delicate fiber things here to have to worry about getting dirty or clean for someone who will point that out on every one of my videos I do where I touch fiber and leave them exposed hi Corey so this right here is the UTP cable and the muxing d muxing of getting all the data and pushing it over this and then putting it back into the electrical signals that come over here creates a lot of latency so while it does functionally work and you can use it it's a solid reliable way to use something and storage over UTP it's not as ideal because the latency you introduced there we're always trying to get the latency lower and lower when especially you're talking about enterprise solutions now also when it comes to the data center solutions they're not using UTP cables for those because these are also used more wattage and wattage when you scale that out you're like hey this only uses a small amount of power you think about the quantity of connections in a data center and you can see this adds up and becomes one of those every minor problem gets scaled out when you build it big so this is great this is convenient this is the easiest and simplest way and how I actually connect my office computer to my servers in the back because well it's really easy to run the cable crimp it on there I don't need to run me don't get me wrong this is really great but if you want to run fiber properly you could use things like a fusion splicer no they're not soup are hard to use but they're more complicated than just crimping hands on cable so throw these over here and we'll jump into these two now the copper that's in here these are direct attach cables so your dad cables are generally no longer than need be they do have some distance limitations and we do know if someone's pointing out scientifically yes lights does travel faster than electricity that being said it's not the light travel where the problem comes in it's the conversion of the media types now when you see some of these articles you always have taken a context that when they were measured and what they're measuring with verses we get better at making electronics faster so these numbers can't change these are stuff I'll link to over from arista but you know all things are taking consideration but as of right now deck is still the winner here in January of 2020 when it comes to low low latency on your storage now the sustain transfer is the same on both you're gonna get 10 gigs of sustained transfer that's great when you're watching a movie but when you have things like data going back and forth transactional data that has to do queries and requests queries in response we want that latency to be the absolute lowest because it may not actually even be 10 gigs at a time it's a very small package so all that little latency adds up because the quantity of transactions at scale and the folks over at Arista have a whole research they did on this and I'm gonna leave a link to all this but this is really cool and they answered a question right at the top that I like this does not clickbait copper is faster than fiber so they have all the why down below but at least they start with that and let's break down you know some of the testing they did and what they do is they tested one two three and seven meter twinax cables and they break down multimode fiber and single mode fiber and the Layton sees introduced into them and this is where things get a little bit different now we know if you're going to go distance you have to use fiber because well they only test Winx up to these shorter distances because twinax only is made for in rack or maybe next to rack distances not all the way across the data center or to the next adjacent building so you have to think about use case and scope for the desktop yes UTP is good for the data center and we got to get it over to the next day instead of running fiber in between them makes sense but for inside the rack itself or maybe if you're just building a storage server you're gonna want to have that lowest latency between maybe your hypervisor system and however it's storing its data so those queries can happen very fast so they break down that now I'm going to jump over here they have the cable Layton sees plotted out so if we plot the results to fit a trend line we get slopes and offsets and then you can start to see and this one right here being the twin axis bottom one here where the cable length only adds a little bit latency generally especially if you're just going server sitting on top of another server you're gonna use the shortest one possible like the one meter one not the seven meter cable and you can see that the really low latency comes in error and there's also that power consideration I talked about DAC cables do use less power than a fiber module and let's jump down to finally the analysis the trend lines above shows single mode and multimode fiber have near identical Layton sees of four point nine six nanoseconds per meter this is close to the oft-quoted five nanoseconds per meter for fiber the latency for twin X copper shows at four point six zero now saves per meter faster by four hundred picoseconds per meter while also interesting a zero offset when we extrapolate down to the hypothetical zero meter cable the copper cables have a lower fixed offset compared with the fiber now I'll go down here a little bit more and this is one important thing I want to make sure it is important for the right medium of job direct text cables have a maximum reach of seven to ten meters depending on devices being used compared to a 300 meter rage for multimodal fighter and a ten kilometer range for the SMF and if they use different ones yes I know there's ones under and I specified what they were using but in conclusion direct-attached copper cables have the edge over both SMF and mff when it comes to latency and I see more prominent in short cable runs because lanes she introduced by the sfp modules it drives the fiber so not just me babbling on this is Arista networks who makes high-end enterprise networking equipment doing the testing to show you what and why it's faster hello these are still like I said great solutions and if you're building out your home lab or something like that this is still if you have to just out of convenience you were able to put the sirs maybe in your basement you want a fiber connection to a second server because you want that one not in your basement where that one was etc or even you know we run into this we have a client who the design and layout of their building created a challenge so they ended up with another server room that is not exactly next to the other one it's not far but it was either tear down walls that were structural support walls or just run some fiber over and have data center kind of split maybe then because the distances that they are on each side of the building you may want to use fiber so you have to think about the use case but when you're doing with things just in Iraq this is still the winner and if it's all in one what in his scales upwards by the way someone's gonna point out what you're talking about 10-gig tom that's old news what about the 40 gig or bigger connectors yes those are still DAC has got the same those same issues have not really been overcome when you do this when you're doing it in rack these are affordable they come in fix lengths they're not too hard to do cable management for and they look really cool when you put a lot of them in I won't lie about that all right and thanks leave comments below or head over to the forms for a more in-depth discussion and thank you for making it to the end of the video if you like this video please give it a thumbs up if you like to see more content from the channel hit the subscribe button and hit the bell icon if you like YouTube to notify you when new videos come out if you'd like to hire us head over to Lauren systems comm fill out our contact page and let us know what we can help you with and what projects you like us to work together on if you want to carry on the 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Channel: Lawrence Systems

Views: 60,380

Rating: 4.9469028 out of 5

Keywords: DAC VS Fiber Latency

Id: jnD0OQRV8LM

Length: 8min 29sec (509 seconds)

Published: Tue Jan 14 2020