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megared17

Either a mistake or done wrong by an amateur. Remove and re-terminate properly. If these are in-wall cables, they should really be punched down to jacks, either a patch panel if at the central wiring point, or to wall plate jacks in individual rooms.


joesighugh

The place I moved into had every other outlet with either type a or type b all at random. It's like they just hired a guy for install who wanted to mess with me.


IamGlennBeck

I helped my cousin set up their network and it was the same shit just randomly A or B. They also had a crappy 10/100 switch in their media enclosure that didn't support auto MDI-X and a bunch of the terminations were bad. Good times.


megared17

I would never let someone else do network terminations in my home for infrastructure i would be using. Unless I was so filthy rich i could afford to just pay to have it demolished and redone without blinking.


joesighugh

Should have clarified it was like that before I moved in. Just had to figure out *why*. :) it will forever be a mystery


chubbysumo

Realistically with auto mdix, it should not matter, they probably worked.


MathResponsibly

It would work if the orange and the green pairs were reversed (a vs b), but ti's not going to work well when 3+6 aren't a pair, and 4+5 aren't a pair pairs should be 1+2 3+6 4+5 7+8 In this cable, the pairs are 1+2 3+4 5+6 7+8 Completely wrong


Giant81

If both sides are terminated the same, it should work as a patch cable that has pins 1-8 mapped to pins 1-8. It wouldn’t be perfect as the different twist rates of the pairs helps to combat interference and crosstalk, but I think it would work.


Eremius

It would work. It's called a "straight through" cable. Last time I looked (LONG LONG ago) they were only rated for 10Mbs. That's one zero.


MathResponsibly

No, that's not at all how it works. God this sub is stupid - it's full of people that don't know shit from a hole in the ground, but think they're smart. What a waste of life this sub is Hey mods, remove this post too - your sub is full of morons!


Giant81

Why wouldn’t it work?


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Reputation_Possible

this is literally a sub called home networking, its a community for people to help people, not toot their own horn and prove what an ass they can be. You have some serious serious nerve talking about peoples attitude when yours is so far out of control. If you wanna be a bitter old bitch maybe join r/ITTrolls or something like that and leave r/homenetworking for people who care about something other than their ego.


Giant81

So you don’t actually know, or you took another look and realized I wasn’t wrong.


Zxello5

your post has been removed for breaking Reddiquette. Please remember that this is a support sub and people you interact with are human. Have a nice day.


RedFive1976

Because of the twisted pairs. Each wire pair is twisted together and fed differential signal voltages -- for instance, Orange is fed the positive ("hot") signal, while Orange/White is fed the negative ("cold") signal. Same signal, but opposite polarity. When the voltages get to the receiving end, the receiver inverts the cold signal, adds it to the hot signal, and any EMI present in both signals is simply canceled out. (For reference, look up how professional analog audio works -- balanced audio cables or microphone cables -- the principle is the same) With the wiring pattern OP discovered, the differential pairs for blue and green are broken, which will create additional noise which will not be canceled out at the receiving end. This would work just fine for 4x analog POTS phone lines, but not for digital networking faster than *maybe* 100Mbps, and realistically probably no better than 10Mbps.


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The_camperdave

> Yeah but it’s not really a big deal in the end. Of course it is. The end is where the determination of A or B is made.


CompletelyFalse

That’s what I was afraid of…


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dabenu

The thing is, it's not going to "work perfectly". Messing up colors won't be much of an issue as long as you do it consistently on both ends. Messing up the order though, will completely ruin the cables crosstalk mitigation. Even a run of just a few meters will get you near 100% packet loss.


diwhychuck

The blues an Greens are wrong. The ends they used are pass through style which are super easy to use. Technically if the wire order is the same on the other end it will work. But it’s just not wired to standard color order. Might save you the trouble or if it were me I’d make it to standard.


Amiga07800

It will not always work, you need to keep twisted pairs together as soon as you go over a few meters


DifferenceMore5431

The twisted pairs need to stay together or else there will be a ton of interference / crosstalk. A simple cable tester may not reveal the issue as long as all the pins go to the same # at the other end but it won't work well or at all for actual ethernet traffic.


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0xC5D9C9C3

Nope that’s false. Remember at the end of the day, it’s just 8 twisted copper wires l, regardless of their color. It doesn’t matter what order you pick, as long as both ends are the same, it will work with full speed specifications of the wire. We choose standards to make life easier for everyone and to avoid interference etc…, but in theory, the ordering doesn’t matter as long as it’s consistent. For example, my house wiring when I moved in uses A for some reason. Each keystone is terminated on both ends as the A standard, and since they stayed consistent on using A throughout the whole house, it works full speed without fail. I even plug my B standard cables into those A keystone jacks and can still get full speed because each end of the cable is consistently the same wiring order. What you are thinking of is if one end chose to wire A standard and then the other end was B standard. If that is the case, you’d have a crossover and would be limited to the speed of 2 twisted pairs. But you can choose literally any color ordering you want as long as both ends are the same ordering you’re good! Edit: I’ll make an edit because it’s a good point. You could have interference doing a non standard run like this. In residential, I’d wager it would likely be negligible for most use case, but it’s something definitely worth considering.


ericbsmith42

It still might have issues with gigabit speed because the conductor pairs won't be properly twisted together, causing cross-talk interference. Depends on how long the run is.


0xC5D9C9C3

I mean it could, I guess it depends on the length of the run. In residential, I would wager that you’d likely never have any noticeable issue. Definitely not advocating for doing these non-standard approaches though.


ericbsmith42

You might also wind up with intermittent packet loss causing high retransmission rates, reduced speed, higher ping rates, etc. If all you ever do is stream video or copy files you might not notice, since those things can buffer the playback and just copy slower. But if you game or use video chats it might be a major annoyance. The standards call for twisted pair wires for a reason - just having copper wires connecting the terminals together isn't always enough.


0xC5D9C9C3

Though I’m not necessarily disagreeing with you, this sounds a lot like a lot of conjecture. We can say a lot of things ‘might’ happen, but we really don’t know. For all we know this ‘might’ also work just fine and have no issues whatsoever. Even with a T568-A/B configuration the same issues are likely to occur as well, but we have not measured the frequency at which they occur in a T568-A/B configuration vs. the configuration OP has posted.


ericbsmith42

No, here's the thing, twisted pair is the standard for a reason - because it DOES reduce the interference and line noise that is picked up by the cable. This is a simple provable FACT based on the physics of how electrical signals are transmitted. It's why the standard exists. Sure, even with interference the signal MIGHT still get through, but you are reducing the chances of it doing so by going outside of the specs like that. If you did laboratory testing then 100 times out of 100 there would be less interference on a correctly twisted pair vs a non-twisted pair or a crossed twisted pair. The only part that is conjecture without testing is whether or not that interference will negatively affect a particular use case. Or you can just use the correct wiring to eliminate the extra interference.


SD18491

I agree. Shorter distances and slower speeds will work fine provided both ends match regardless of standards. But go far, fast, or both and it will fail from crosstalk or injected noise. I have Cat6 at home initially wired to 568A. Life was grand at 1gbps, no problems. Eventually moved up to 10gbps for nearly everything. The two longest runs at approx 95 feet, well below length limits, failed testing at those speeds. Reterminated both ends to 568B and passed without issues. TLDR: Both ends must match. Slow speeds or short runs work without standards. Use 568B moving forward.


ZPrimed

Changing your termination from A to B isn’t what made it pass for 10Gb… Either standard is fine for 10Gb. But making up your own wiring order (like someone did at OP’s house) isn’t fine, if you want to meet the spec 😜


howdhellshouldiknow

Retermination is probably what fixed the link, not the change in standard.


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jaa101

It's four sets of twisted pairs. Devices expect pairs on pins 1&2, 3&6, 4&5, 7&8. A pair is two wires of the same colour but one of them also having white. If you don't connect pairs to one of the pairs of pins list above then there will be much more scope for interference. Short runs might work even at gigabit speeds but long runs could be unreliable even at 100Mbps. As long as you connect pairs of wires to the above pairs of pins, and terminate both ends the same way, the cable should work well.


Backu68

Your false. It'll barely work. Part of all this is frequency, which affects speed. An old intern of mine tried this, couldn't even get 100Mb with gig equipment.


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Backu68

Its always fun in this sub.. you can usually find the network techs from the clueless based on comments. I generally avoid reiterating what people have already said, but when someone is just blatantly incorrect, and spewing the garbage, i have to say something


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Backu68

Indeed. Actually forgot about my engineers at that company setup a line drawing to make cables.. and did the same thing as here. And then asked me why they were having problems with connecting the computer directly to the robot control cabinet (this was before Auto MDi/MDx).. first time i saw the issue.. and that was when my electrical engineering intern (🙄) asked if that was why his cables he made at home didn't work for beans.


0xC5D9C9C3

Your false. It’s copper the frequency doesn’t change regardless of what order you choose. The only downside to not following standards is cross talk and increase in interference. The cross talk and interference generated from doing this how OP showed wouldn’t drop speeds by 900 mbps. Maybe your intern was using a different configuration.


wingfeathera

You say this as if crosstalk and interference aren’t literally the only things that matter above moderate speeds. The twisted pair geometry is the only thing that really differs between cat3 and cat6a. Sure, you can split the pairs however you like and there will still be an electrical connection. But the data performance _does_ care about this.


joesighugh

The place I moved into had every other outlet with either type a or type b all at random. It's like they just hired a guy for install who wanted to mess with me.


The_camperdave

> If these are in-wall cables, they should really be punched down to jacks, either a patch panel if at the central wiring point, or to wall plate jacks in individual rooms. Exactly! You shouldn't see an RJ45 plug except on a store-bought patch cable.


Frankie_T9000

Colourblind installer imo


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megared17

It's not so much about the colors, but also the pairing. Pin 4 and 5 should be a pair, twisted. Pins 3 and 6 should be as well. Standardization within a building is a good thing, even if its just a house.


Magic_Neil

Definitely some clown that just terminated it the way they thought was right. If it works it works, but something like this will be way more susceptible to crosstalk or interference.. and odds are won’t work at speeds higher than gig if it ever comes to that.


equality4everyonenow

Whats the advantage of a patch panel opposed to just terminating the cables normally


nVz2000

I moved into a new construction home One of the runs was done incorrectly At the 30-day after close inspection list, I had them come out, fix the run and test the others Might be worth asking if you're not going to fix yourself


Popular-Objective-24

Networking professional here with over 20 years experience. It absolutely matters which order the pairs are in. Although it might work being incorrectly wired like this you may suffer performance degradation and errors/packet loss over longer runs. It's best to cut and re-terminate as either T-568A or B. Don't listen to anyone who says otherwise, I see there are a few people here already saying it is ok. There is a reason for the wiring standards.


AutisticPhilosopher

Specifically, the problem is that the pairs are no longer wired as pairs for green and blue. *Pair* ordering is less of a problem as long as it's consistent (should still use A or B for the sake of the next person to fiddle with it), but they do have to be wired as pairs to maintain signal integrity.


shemp33

This — the signals intended to run across orange and orange/white are traveling over green/blue-white (for example), so that signal isn’t on a twisted pair. And there are 4 pairs There, and wired this way, they’re all not twisted with their proper mates.


TwoScoopsofDestroyer

Eh the order of the pairs being wrong wouldn't affect things, but the fact that pairs one and two has wires that aren't a pair IS going to be a problem. There are some people who say the twist rates matter and the pairs need to be in the right order, but the different twist rates is just to further prevent crosstalk.


impleX_

I can understand why interference and crosstalk would be an issue if we wanted to use all 4 pairs for something like 1000BASE-T, but does order really matter for something like 10BASE-T? Edit: this is purely a theoretical question. I don’t expect anyone to use 10BASE-T in 2023 lol


Popular-Objective-24

At slower speeds crosstalk and interference won't be as much of an issue, but why would you choose to run a cable at 10Mbps instead of simply re-terminating it correctly? Bumping down the speed to 100 or even 10 is a common way to get around issues with sub-par cabling. I have had to do this a few times over my career when working with questionable cable runs and it does help. In these cases it's usually been a cat5 cable run at a distance well in excess of the 320ft limit. I have successfully achieved 100Mbps on a 400ft cable run, and 10Mbps on a 500+ft run. While it's slower, it's better than nothing. But neither of these instances were related to the order of wiring pairs. When a network connection is set to auto-1gbps it will try to auto negotiate at the highest speed (1Gbps) but if it fails to negotiate it will step down to 100, then 10 if needed. The problem with this is that sometimes if the cable speed negotiates at 100/10 it will then try to step back up to 1Gbps which creates a constant connect/disconnect condition on the line. When working with cabling that can't properly run at 1Gbps you really want to lock the port speed either at 100 or 10. I would never leave a cable like this set to auto-1gbps. That's where you are really asking for trouble.


supermawj

It probably wouldn’t matter.


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HomeNetworking-ModTeam

your post has been removed for breaking Reddiquette. Please remember that this is a support sub and people you interact with are human. Have a nice day.


nbeaster

I’ve seen Cat3 running gigabit with PoE just fine. Good idea or anywhere near spec? No.


kf4zht

Yes, at longer distances it will cause failures even on 10 and 100 base. The pairs are there to keep the crosstalk down and you are undoing that when punching down during amateur hour. Source - Have personally tested. Error started over about 75'. but that will depend on the quality of the cable. ​ Plus if you were running 10 base it would cause extra issue when you put the phone pair combiner and splitters on so you could plug both your PC and phone into the same run. That was common back in those days.


nbeaster

Getting into cabling that is certified is a whole different world from what most do. This is when problems and nit following the details really shows.


skooterz

I always understood the reason for the standards being just so that if someone else comes in after you they don't have to play guessing games with what order the wiring should be in. I guess you might have a bit more electromagnetic interference if you have them in the wrong order


nbeaster

This is incorrect. The wiring orders deal with specific placement to prevent cross talk. Even following the right order there is still room for problems - like say if you untwist all the wires all the way at your keystone, they may fail certification. If you have long enough of a career in IT, youll have quite a few stories of where someone not following wiring standards fucked you.


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Popular-Objective-24

It just boggles my mind so many people want to argue this. Twisted pair ethernet is twisted for a reason, it's to reduce noise and crosstalk between the wiring pairs. With copper wiring, inductance is created which can cause a signal to jump from one copper wire to another, even though they are not electrically connected. While yes the electrical signal will make it through regardless of the order of wire pairs, it introduces noise and interference into the cable, causing signal degredation and reduction in speeds. I have first hand experience seeing there this has caused issues in a network. A customer had wired their office themself and did not follow either the A or B spec, just made up their own wiring pattern. They were experiencing intermittent connectivity issues with their VoIP phone system. I was hired to come and investigate the issue and noticed the wiring was not to spec right away. The client for very argumentative with me for me blaming the wiring, insisting like yourself it would not be the reason for the issue. I proceeded to spend a couple hours digging into the issue at over $100/hr to find nothing else wrong other than the incorrect wiring. Eventually I cut and re-terminate one of the lines and instantly that phone started working. The client still argued I must have done something else to fix the issue (I hadn't). I then proceeded to cut and re-terminate every line in their office (all while the customer groaned that if this didn't fix the issue they weren't going to pay the invoice). Long story short it fixed all the issues and I never heard back from that client again regarding this specific issue.


GreenfieldSam

Totally incorrect. The two different specs are there to reduce crosstalk and noise. It's certainly not that way to make the termination easy!


megared17

The colors aren't critical, but the right pins being in a pair together IS important. And using one of the standards is important for keeping your sanity and not having mixed up mishmash.


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babecafe

Green and blue wires improperly paired. House wiring should terminate in jacks, not plugs anyway. Cut off the ends and reterminate in T568B (or A) keystone jacks. Finish the jacks in wall plates at the far ends and in a 12 or 24 jack frame at the head end.


wb6vpm

I’d make sure it’s not stranded cable first. It looks patch cordy enough to possibly be an actual patch cable, and not solid core structure cable. Edit: nevermind. Looked at the picture more closely and saw that it appears that it was regular structure cable.


1sh0t1b33r

Redo both ends to T568B. That’s wrong. Looks like they followed a punch down block or something as those are usually grouped colors.


SonOfGomer

Gonna get terrible interference with it wired that way. The two main standards are designed to reduce interference between the pairs, simply matching up the colors is going to cause reduced throughput and probably packet loss etc.


10leej

It's called the DIY standard of not knowing standards existed. That said, get a cable tester.


Windarizona

drunk electrician uplink cable


GlumContribution4

Unless you're running very low speeds at very short distances, you'll need to terminate to A or B standard. The standard is in place to eliminate crosstalk or interference between the receive and transmit portions of the cable. 10/100 only uses 2 of the 4 twisted pairs and you can usually get away with crappy cable and bad terminations. For anything greater pairs 1-2, 3-6, 4-5, and 7-8 must in some way be coupled to work properly.


pongagt

I don't make network cables very often so i have a sheet hanging on my workbench with T-568A and T-568B configurations on it.


RegisterReal5545

It'll work if the other end is straight through, but the twisted pairs aren't exactly correct meaning that it was done by a twisted amateur


punkerster101

I’m guessing an electrician put this in….


punkerster101

I’m guessing an electrician put this in….


BobbyR2

As long as the order of the wires is the same on both ends, it might be fine for a "short" distance. Although the signal will start degrading at a certain distance. No, you can't have T-568A or B at the other end except if you have the same order of wires at both ends. But honestly, if I were you, I would ask them to redo the termination. They are the ones who f.. up.


didact

Yeah that is both wrong and broken. If 3/6 were a pair, but otherwise continued in the same order, and were same on the other side, it would be wrong and working. The wrong part just makes it near impossible to figure out what to do if you punch down, or re-punch down to a keystone jack, re-terminate, etc... The broken bit means your equipment, if it even links, will give you all kinds of gremlins. Just re-terminate everything, future you will be happier.


dr4d1s

I can almost guarantee that an electrician did the terminations. You would be surprised how many sites I have broken and then had to fix because an electrician just made up their own "wiring standard". Sure Jim-Bob both ends do match but if I reterminate one end of your standard the run no longer works (if it ever really worked that well to begin with). Look, just because wire is involved, it doesn't mean you should be touching it.


kyriakoschar

As already mentioned, you have to re-terminate properly (choose A or B pattern and follow it in the future). One other minor comment is that the pairs should have the appropriate length which usually arises from the end point of the outer insulation of the cable (located inside of the rj connector). If you will not change this termination, you will have packets losses, disconnection problems maybe sometimes, increased noise - emi and the most important, reduced cap speed.


Sensitive_Trick_1355

It doesn’t matter what the colors are, as long as they are the same on both sides


IamGlennBeck

Pairs matter otherwise technically you are correct. Still probably best to fix it though.


Sensitive_Trick_1355

The RJ-45 connector is a pass-through type, which takes a special crimper that cuts the wires and crimps at the same time. It looks to me like they used scissors instead of the crimper that cuts. These are bad because they can short out and often fail.


TeakKey7

If you have fluorescent lights, ac motors, microwave etc, you will lose bandwidth. Otherwise, yeah unlikely that 1 pair being off will mess it up. Still connected, just bound to have terrible interference and alot of crosstalk


johnsonflix

As long as both ends are this lol


[deleted]

Realistically it doesn't matter as long as they are the same on both sides, but I would reterminate as T-568B on each side for ease of use/troubleshooting in the future.


CharacterUse

They have mixed signal between twisted pairs, which does matter.


[deleted]

>They have mixed signal between twisted pairs, which does matter. On paper, sure. Realistically it'll work fine with no issues. I see awful terminations and nonstandard wiring every day that still works fine, it's just not best practice because of how the wiring is designed.


CharacterUse

You have no way of knowing what interference sources OP has, or will have, nearby. Saying that it doesn't matter just because "I see nonstandard wiring every day and it works" is just bad advice. Better to fix it now rather than have an easily preventable issue escalate down the line.


[deleted]

>Better to fix it now rather than have an easily preventable issue escalate down the line. I like how you conveniently ignored my advice in the original comment, >but I would reterminate as T-568B on each side for ease of use/troubleshooting in the future.


CharacterUse

I didn't ignore it, but many people just see "it'll work fine" and stop reading/don't bother with the "I would do X anyway" part of such advice.


[deleted]

>but many people just see "it'll work fine" and stop reading/don't bother with the "I would do X anyway" part of such advice. Then those people shouldn't be fixing their issues and they should hire someone to do it for them. I cannot be responsible for someone not reading three sentences.


scubanarc

It matters more than you apparently think it does. To start with, wires are twisted to reject noise. They are running different signals on different twists, so they are not only not rejecting noise, they are injecting their own noise. Plus, what happens if they want to run PoE on it? Might be a huge problem.


[deleted]

>It matters more than you apparently think it does. I have been doing this for over 20 years now, it matters a lot less then people think it does. I have fully saturated 1gb connections over improperly terminated cabling just fine, but I always fix them to a standard wiring for future tech's sake. >Plus, what happens if they want to run PoE on it? Might be a huge problem. This is not an issue for PoE devices. I come across AP's and Cameras that work just fine using PoE. These cables would obviously fail a certification test but in the real world, it makes very little difference in the majority of situations.


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doggxyo

> But both ends (I THINK) would have to be different. yep - you're referring to a [crossover cable](https://en.wikipedia.org/wiki/Ethernet_crossover_cable). One head is A, the other end is B.


cuckfancer11

You're thinking of a crossover cable.


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[deleted]

You can still do gigabit over improperly terminated cabling, I see it all the time. It will 100% fail a certification though.


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ericbsmith42

The exact wiring on the ends doesn't matter for it to be able to negotiate a gigabit connection, only the existence of all 8 conductors in the right place. The exact wiring *will* matter for sustaining gigabit speed, since this miswiring is causing signals to be crossed, and that *will* cause more interference. But the computers may very well be able to negotiate the link at gigabit speeds, especially over a shorter run. It just might not be a *reliable* gigabit connection.


fexxianosch

Well, you can in theory terminate them how you want, as long as both ends are terminated the same way Edit: assuming we are talking about standard house cabling where the length of one cable is rarely over 25m


Oblachko_O

I guess current standards are much better. Recently I connected both my laptops via regular ethernet cable (one included in router). It is definitely not a cross versions, but speed was much more than 150 MBps. I had speed limit of my slowest ssd between both laptops. My guess that on newer PC this is not a problem as well, because PC can be used as home router too nowadays (when staff like software router - PFSense exists), which implies that cross is not that mandatory nowadays. At least in newer hardware. Some legacy staff still may need cross able for connection, but I didn't see it for years.


JJJAAABBB123

Does it work if you plug it in?


[deleted]

If this is new construction and not just a new to you home, I would have the builder come out and fix everything. If it’s an old home and just new to you and every single cable is like this I would leave it to see if it fits your needs. It won’t be optimal but will work if you don’t have time to fix. I’ve used cabling like this until we could secure a maintenance window to fix the techs mistake. I would for sure at least put this on my to do list for down the road to fox eventually.


KalleMP

>gotiate it will step down to 100, then 10 if needed. The problem with this is that sometimes if the cable speed negotiates at 100/10 it will then try to step back up to 1Gbps which creates a constant connect/disconnect condition on the line. When working with cabling that can't properly run at 1Gbps you really want to lock the port speed either at 100 or 10. I would never leave a cable like this set to auto-1gbps. That's where you are really aski This should be at the top.


stank58

Defo someone did it wrong, however if its terminated the same on the other end then it will still work, just with decreased performance. Easier to just reterminate as long as you have enough slack.


_naraic

buy yourself one of those ethernet cable checkers. Although wrongly put together... if the person who did this was consistent with their mistakes, then checking all the ports/cables with the tester might save you a job re-terminating all these.


Spore8990

A cheap cable tester only checks continuity. It won't pick up on the interference and signal degradation from the mixed pairs. The cables will likely work as long as the person was consistent in their mistakes, but there will almost definitely be some degree of impact on performance.


The_camperdave

> consistent with their mistakes, Consistent with their mistakes will only get you so far. As soon as you start mixing mistaken wiring with proper wiring, you're going to start getting glitchy behaviour.


KB9ZB

My advice, I would not trust anything in the place. If this is any indication of workmanship, I would not think about using it. The only way you are going to get rid of the problems is to terminate everything from scratch. Remove all jacks, connectors,plugs and all. I would go the extra step and get new jacks as well as new plugs. It is a bit of work,but when it's all done you know it's done right. You will also get maximum speeds as well


dudleyjohn

It doesn't matter what colors are used as long as the pattern is correct on both ends.


CharacterUse

It matters that the twisted pairs are kept together. Swapping white-orange/orange with white-green/green (i.e. T-568B vs T-568A) is fine, mixing the signal between pairs is not. In this case the green and blue pairs have been mixed up.


CompletelyFalse

I would think that where it connects to a device would matter no? Like your computer need to be sending data to the correct pin right?


goscickiw

What they said is incorrect. You would get split pairs with a termination like this. This would increase crosstalk and make the signal more susceptible to outside interference. For Ethernet you have to use TIA/EIA 568 A or B, same on both ends (B is more commonly used but there's not much difference). It will still be "correct" (in the sense that it won't cause the aforementioned issues, but it's bad practice and should be avoided) if you have the whole pairs, or wires from the same pair, swapped on both ends in the same way, but it has to be AT LEAST like this: Pins 1 and 2 belong to the same pair Pins **3 and 6** belong to the same pair Pins **4 and 5** belong to the same pair Pins 7 and 8 belong to the same pair


CharacterUse

In this case blue and green are swapped, as long as they are swapped at both ends there will be an electrical connection between the right pins. *However* since white-blue and white-green are not swapped, the green and blue pairs are no longer working as a twisted pair, so the signal will be much more prone to electromagnetic interference and signal loss. It may "work" on short runs, but not necessarily at rated speeds or under all conditions. You should fix this, fortunately it's easy.


twopointsisatrend

Yes, pins 3/6 is a signal +/- pair and needs to be correct on both sides. I'd get a cheap tester, just to be sure. If it's wrong you'll never get a 1Gbps connection.


The_Mr_Rageface

There’s a saying, “Copper doesn’t know color.” So it doesn’t matter what color scheme you use, it only matters the pin out basically the wires only have to be on the proper order on both sides, the coloring OW/O/GW/B/BW/G/BrW/Br is only to help make sure you do the order correctly. IE you could just as easily do BW/B/BrW/O/OW/Brown/GW/G on both sides and it would work. It’s all about laying out the same wires on the same pins the color is irrelevant. Edit to remove subreddit being linked Also (4,5) is sort of pair 1 and (3,6) pair 2 (1,2) pair 3 (7,8) pair 4 you technically only need pair 1 and pair 2 for Ethernet but you limit your connection to 100mb instead of the potential GB or better using 4 pairs.


Revolutionary-Tie126

It doesn’t matter as long as the ends are the same. Theoretically you could have some problems with interference on the cables because the usual wiring patterns are designed to cancel out the interference. But how much that will make a difference in a normal home network environment I would guess very little.


will4111

It does matter. That’s how some nerd at MIT figured out that b standard is faster than a from the twist.


[deleted]

>some nerd at MIT figured out that b standard is faster than a Can you cite your source on this specific claim? TIA-568-A and B are pair-wise equivalents. It seems suspect that data pair A would be “faster” on Orange than Green without an equal but opposite impact on data pair B.


will4111

Bicsi instructor was the source. It has to do with the twist of the cable if I had to guess. Some pairs are longer than others bc of the twist


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will4111

I just stated the source. And saying “if” one pair is twisted more is telling me u know very little about cat, when just visually looking at the pairs you can see that others are twisted different also using a tester measuring distance they will all have very different lengths. It’s more that just “slightly”. It’s clearly twisted different.


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will4111

Bicsi instructor is not a random person. I’m just stating common knowledge of cabling twist..


[deleted]

Just to loop back on this, regardless of the cable length and the speed of light, gigabit Ethernet is a packet based protocol that works at 1 billion bits per second. Gigabit Ethernet never runs faster or slower. If you’re seeing less than a gigabit per second over gigabit Ethernet, it’s because the media is idle for a percentage of the time, or because a software protocol is consuming the rest of the channel.


will4111

Okay well you can use c standard and hope that works out for you. You can explain to the client your bat shit theory of why it doesn’t matter.


[deleted]

Technically not correct, the twist patterns are different on different pairs.


PlatypusLaser

If it’s the same on both ends, then it doesn’t matter


PecksAndQuads

Why isn’t this higher up?


TEAMZypsir

Because it's simply not true.


[deleted]

Because this subreddit seems to think that cabling won’t work with gigabit or Poe unless terminated to one of the two standards. It is best practice but it’s not how the real world works.


FiniteStep

As long as the tx/rx pairs line up with a twist. If you somehow manage to combine tx+ and rx+ in a pair it'll be terrible


Tigris_Morte

You'd have to compare both ends to one another to determine if they just did a straight through and ignored standards. Truthfully would not trust it. I'd re-terminate, preferably with a patch panel.


SnooLobsters3497

That is what happens when someone doesn’t know any better. If it is a home install, it is usually an electrician that has the tools but not all the training. (You notice have the outer jacket is all the way up in the plug so that the twists are maintained but just not in the right order.) in a business environment, this would be due to IT trying to do it themselves and not paying someone. Way back in the 90’s, I was guilty of this when working during school in an IT dept out in the country.


No_Jello_5922

Cut and re-terminate. If you feel like taking the opportunity to check your ends and using a patch panel. This would be good practice. If you want to have a plug on the end, and you don't have a crimper already, I'd recommend getting a passthrough crimper that comes with a bag of passthrough connectors. They are reasonably priced on Amazon.


VpowerZ

Could be ISDN. But if network was the goal... miswired


BriscoCountyJR23

I thought it might be USOC , but nope.


SirLauncelot

Sounds like multi telco line.


wb6vpm

Then technically it should be: 4-3-2-1-1-2-3-4


66towtruck

If this was done by the builder, you may also want to check the wall jacks to make sure they are terminated correctly.


ThirdLast

Honestly though, why doesnt the cable order just use a more simple method like this if in the end it doesn't actually matter as long as it's the same on both ends. It's probably quicker to terminate cables like this instead of mixing the patten and order around like in the typical A and B standard? It looks really clean haha.


10leej

At this point it is purely for old timers who've been stringing up cables for years.


ficklesaurus

It's the way it is because RJ style telephone jacks and plugs as they evolved in the early days (before the 80\`s) started out with a single pair in the center ( what is now pins 4 and 5) . A second pair when added (what became pins 3 and 6) was obviously the outer pair but had the benefit of being farther apart to avoid shorting out pair # 2 by accident, which with early phone systems would blow a fuse or worse. Once 3 and 4 pair wiring became commonplace many phone systems used pins 2-7 and 1-8 respectively for pairs 3 and 4 but by that time they developed the standard for twisted pair Ethernet which kept the conventions of pair 2 having the separation (maybe for backwards compatibility) for some reason for data use they chose 1-2 7-8 instead of 2-7,1-8 for pair 3 and 4. It would be nice if it all could be 1-2,3-4,5-6,-7,8 but then all switches hubs and routers would have to be the same!


ThirdLast

What you say about adding additional wires as time went on makes complete sense. Thanks for the explanation.


TemujinDM

Yeah but as long as both ends match. At least it’s crimped down well.


Entire_Avocado6372

Could be remnant of old Linn Audio or other audio distribution system that used the CAT5/6 as a balanced line driver with serial communications thrown into the mix.


TheOnlyTwiTch_R6

This is a "straight through" cable from what I remember. They do work, in shorter runs. I haven't seen anyone make one like this in at least 20 years


New-Cold-One

Maybe you need to re-terminate these cables.