There’s NO WAY this works - Debunking bogus network splitters.
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- Опубликовано: 9 июн 2024
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Ethernet splitters are all over the internet, but aren’t they just a scam to steal from the uninformed? Well, mostly. But with a little knowledge of the history of networking, you really CAN run two devices over a single network cable!
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CHAPTERS
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0:00 Intro
1:15 Andy's Car Collection
1:14 Let's try them out!
2:16 The Headphone Splitter
4:06 What's going on here?
5:40 Networking like it's 1999
6:51 But Linus...
8:55 Outro 
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Since reading comments from you beautiful people, we want clarify a couple things. First, the fact that ethernet is digital (as opposed to analog) is not the reason that these splitters don't work. In fact, some digital signals can be split, such as I2C, DTV, or ARINC.
Second, many other commenters are suggesting using these splitters as passive hubs, but while in the past that could have been a possibility, these splitters aren't wired correctly for that . The transmission pins on the sending device need to connect to the receiving pins on the other end. Simply wiring pin 1 to pin 1, 2 to 2, etc. as we see here does not work.
While some of those old/deprecated features of the earlier ethernet standards could have enabled devices similar to these to work with very old network adapters, few, if any modern network adapters support these features and, ultimately, the wiring diagrams presented on the product page for these don't suggest that the seller intends customers to use them in that way.
Our apologies for not making all this obvious in the video! Now here's some link to real solutions:
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Hi i love your content. Your the best
when the h
the earliest ive been
I'd love to see a Coax TV hooked up to HDMI.
could you please make a video about ethernet wan aggregation, like using qhora 322, or peplink, or asus new 10gbe routers to aggregate 2 or 3 different isps to get more "speed" (essentially getting 1 output with all of the speeds combined)
It's honestly impressive these companies realized less technically inclined people would search for "ethernet splitter" instead of an actual switch, then made a product that looked exactly like what said people were expecting, albeit somehow worse and more expensive than a 2-port ethernet switch. If only they had used their powers for good...
it should've worked like a hub if they configured it correctly i guess??
"And so one more finger curled up on the monkey's paw"...... 😂❤
@@divyamthakur that's exactly what a switch does
edit:
ok nevermind I'm wrong, still if you want to explain me the difference go ahead, i like reading explanations :)
When money is involved, rarely are the motivations humanitarian.
@@divyamthakur I guess I'm a noob but I always kinda assumed these things are basically a hub? what is the diff?
Time to daisy chain splitters into a Christmas tree of sadness.
Ok
😔
How many times do you think that's been said😂
🎄😢
This commenter knows sorrow.
I made this back in college. Had 2 machines and I was lazy and didn't want to run multiple cables and we didn't have access to a bunch of consumer grade switches. There was already a jack at my station so I made my own 'splitter' with 6 Rj45 connectors (3 at each end). My networking instructor was both disappointed and impressed when he saw it. He knew I knew it was wrong. But also, he appreciated the ingenuity of it.
Awesome
This kind of setup is how telco gets run as well. 4 pair, 4 phones.
You also probably didn’t screw yourselves over by slamming into a hub that also requires crossover cabling. 😂
Tbh I saw properly cabled (that is 4 wires on one port and 4 on the other) splitters in several industrial installations.
Expecially in not big warehouses where fiber was not needed
@@TheInsomniaddict Telco is not ethernet. who cares?
I used to make my own splitters in the military when running another cable wasn't possible or feasible. Was back in the Cat5e days, so we only had 100Mbps switch ports at the edge anyway.
Thanks for bringing back some good memories! 😂
Hi Linus, random network engineer speaking. That splitter might work if you change all of your network interfaces to half duplex. Half duplex would need to be set on both of the computers connected to the splitter as well as the switch port the splitter plugs into. Half duplex uses a protocol called Cable Sense Multiple Access with Collision Detection (or CSMA/CD for short). Its a protocol that harkens back to the days of yore when network devices communicated over a single wire (like token rings and hubs). On a Windows PC you should be able to change the duplex settings from the network device properties in device manager. As for the switch, you will need a managed switch that allows you to change the port settings.
Thank God there are other network engineers here!!
You mean Carrier Sense
yeah I was thinking the same thing. Effectively those splitters are just a shitty hub. CSMA-CD is enabled in half duplex settings, but not sure if the consumer grade switch supports half duplex.
Yeah, thanks. I was on the verge of screaming at my computer screen: “google how Ethernet hubs worked bro”.
With that said, I wonder how tested most NICs are these days to work in a collision domain containing more than two devices. That’s all modern NICs usually have to deal with thanks to the advent of the switch.
I experimented exactly that in one of my projects, and it doesn't actually work. Reason being standards like 10BASE-T, even when set in half duplex mode, still uses the same two pairs as tx/rx as full duplex, but there is no way to electrically connect those two pairs together so all devices on the bus can share them. I did find there's a 10BASE-T1S standard that does exactly what I needed but the ethernet chip I had didn't support it so I didn't continue that.
edit: by "work" I meant all devices connected together this way can talk to each other. I was able to get one device to talk to other two even at full duplex, but not between all three devices I had at the time.
edit2: I was actually experimenting with 10BASE-T, not 100.
I did this once a couple decades ago. The building facility manager would not cooperate between our two suites, so I used the telephone panel to split each pair to their own phone jack in the closet and connected the switches via a custom cable feeding all 4 pairs back into an ethernet keystone on each end. Performance was good enough to allow us to complete the move from one suite to the other over a week instead of having to do it overnight. Once done, I removed my handiwork from the closet and kept the two dongles as a trophy for my ingenuity. :)
I did this once to run DSL and Ethernet over a single Cat6 cable, it worked, but was replaced as soon as a second wire way pulled through the wall
What would happen if you inverted the cable. 2 cables into a single port on a pc?
@@nolan33 Depends on how the network card / chip handles it. You will either connect to just one of the networks or to none at all, plus you will be limited to 100Mbit/s as gigabit needs all the 8 wires connected to a single port on both the switch / router and pc.
We used to split CAT-5 cable into two cable connections when I was in the Air Force all the time. My unit's mission was to setup deployable PC/telephone equipment in the field and the less cable we had to run the better. We would even drop a ethernet link to a PC and then use the extra wire pairs for telephones.
And that's why you lost the Vietnam war! "Hello? Hello? Is that B company? It's no good, Sarge, these PC/Telephones don't work! I think it's this splitter" "Well drop some napalm and fly back home then"
I've done that on a site with AT&T 110 patch panels. The Ethernet connection used two pairs, and one of the remaining two pairs were used for a phone. No pairs were shared between the two devices, and the frequency difference between the Ethernet service and the other service were so different that there was no crosstalk, and each service worked as expected. There were no ethernet errors (switch error counters proved this) and no weird audio artifacts on the phone.
Vodafone tech here. Can confirm. Linus is missing this out completely... As usual.
I agree the video creator doesn't know very much about signal flow and electronics.
I've been splitting ethernet wires for phone and high speed internet in small businesses and single family homes since 1999.
Surprisingly, this video has helped me diagnose a network issue at home today. I noticed that a wired connection between 2 rooms is running at 100Mbps, which led me to think that one internal wire is broken/disconnected. I never realised that we can run 100Mbps with less than all cables before I watched this. Sure enough, pin 4 is coming back disconnected. All the other wires are good. Not the point of the video, but it helped me diagnose the issue 👍
Yes that is weird...I got Maxwell's theory out of it double your baud rate.
Tech tips??? On my LTT?
That physical diagram between the garage and living room was perfect and made everything extremely easy to understand. I'd love to see more like that in the future.
Me breath through mouth too.
Me like visual aid.
I was genuinely impressed with how good the example was
@@highrider9168 How rude.
Reminds me of the old (before the 90s) educational programs that relied on physical props for demonstration, like "The Secret Life of Machines".
@@DrewTNaylor then read it a different way.
😂
This video's sponsor looks like it helps to build many of the experiences I hate about trying to shop online.
Elaborate?
@@Kyle_G_Sy Drop shipping is a a method of scamming pretty much, and a get quick rich scheme at best.
Thats VERY simplified and generalized. Almost all of amazon is dropshipping. 80% of online stores are dropshipping. Nobody cares. The problem is when it's used to scam someone and products are never sent or only after months of waiting.
@@theresoluxion you'd think tech savvy viewers of LTT would know reselling chinese crap for insane markups is scamming, but you dont seem to
@@okaydetar821false. Dropshipping is a logistical method of moving product that's been used for 45yrs however once in a while like with anything. Someone runs a scam. And then dodo brains automatically assume everything is a scam as a result. Their problem not logistics problem😂
Fun video. What you built here was a Data / Data RJ45 Economiser, you can also buy them in Data / Voice and Voice / Voice. They often have different colour strain relief boots to indicate by glance what they are. Basically on the Voice versions they are wired up using the middle 2 pins (Pin 4 and 5 blue pair) and the brown pair (Pin 7 and 8). They have been around for many years, but not many know about them 👍 The Data / Voice version is sometimes useful for pushing good old fashioned dial tone down the 1 Ethernet cable with 100Mbps internet as well.
Voice only requires a single pair, doesn't it? You should be able to to 1gbps data + voice.
@@TheInsomniaddict Yes, voice only needs the 1 pair, there are instances in the UK where you might want to push through the ringer wire on the 3rd wire so it could need 3 wires to work. Unfortunately even with voice using 1 pair that leaves only 3 pairs remaining, so you still wouldn't get 1000Mbps which requires all 4 pairs, you are still limited to only 100Mbps which is still fine for most things 👍
@@Mymatevince Darn, I was thinking it required 3 pair with the 4th for shielding. Ah well.
> "The Data / Voice version is sometimes useful for pushing good old fashioned dial tone down the 1 Ethernet cable with 100Mbps internet as well."
Exactly what we're doing to get our Ooma base station networked, and its phone line interconnected to our central phone block. (Although we made our own phone+FastE splitters. The few I saw offered commercially were ridiculously expensive.)
There also exists a 4 x voice Economiser. Voice uses 1 pair. Ethernet 10/100 uses 2 pairs. Ethernet 1000/2500/5000/10000 uses all 4 pairs.
As a teen during my LANning years, the staple LAN was the 'Organised Chaos' one held by two brothers who'd attended the 'Springbok LANs' before that. Starting out with building their hardware etc, as a cost-saving measure they would run a single CAT4 cable from a hub or switch to a given table, intended for only two computers. In this way they were able to utilize only half the cables to support 100+ 'man' LANs pretty quickly, which you can imagine in the early 2000s was still a pretty significant cost-savings for highschoolers.
I've never heard of CAT4 cable being used for Ethernet (or anything else). The first cable type was CAT3 for 10 Mb, then CAT5 for 100Mb & Gb.
Working at Radioshack I heard this a thousand times. We had an adapter that was exactly like the adapter featured in the video. They would refuse to buy the slightly more expensive ethernet switch regardless of how much I protested. Some of them came back and usually apologized; others I'm sure went to other stores to avoid seeing my face again lmao
Was it the white triangle shape with 3 ethernet port? If yes i had it and was working not so bad.
@@dominiquebeaulieu7476 nah it was two ports and two came in a pack
How bad is your face?
@@Aguyinachair I do remember those. I also was $hackled for a little over 3.5 years. They were definitely a boomerang sale. The customer insisted, I told them otherwise, they wanted it anyway, but I warned them. Surprise, surprise, it was returned time and time again.
I actually have needed and 😅to use these things. Mostly for partyline comms systems like ethernet controlled light switchs and other things like arduino networking. They do work, but are extremely niche and not for splitting internet like joe blow wants
I've been using 100Base Ethernet cable splitter pairs quite successfully for years. Yes, they work the way that your made yours. Thank you for explaining important considerations, limitations, and how they work!
Here's why I use them:
A good application for a 100Base Ethernet cable splitter is in a managed network that has Mode A PoE clients located in extreme temperature environments away from a local power supply. Although weatherized industrial PoE-powered managed PoE switches are available for use in such applications (e.g. PoE security cameras, especially where you have a cable to one camera and need to add a second camera nearby), the cost of these switches is much higher than the indoor switches in your links. Adding a managed switch can add additional maintenance needs (unless it is an automatically maintained network, which can also drive up the cost of the switch) and it adds another point of failure (including attracting possible theft of an outdoor switch that costs more than a the equipment connected to it). The passive cable splitter pair never requires maintenance, it requires no power, it is compact, it's extremely reliable in harsh environments, it can consolidate network device surge protection to one end, and it's very inexpensive. For 100Base Ethernet Mode A PoE, it just works and keeps on working.
bro i love how in every video this man makes a perfectly smooth segway into the sponser
As someone still occasionally having to deal with the "proper" splitters, I can tell you they've been around for ages. And they're an absolute nightmare. Because the venn diagramm of people who use these, and people who don't document jack shit in their network, is perfectly aligned.
Oh and also, finding replacement ones for situations where the customer absolutely does not want a better solution (because why would you?) has become a giant hassle, because everything is saturated with the "fake ones" as dropshipped e-waste. Thanks for the sponsor by the way, that particular industry absolutely needs to become bigger.......
Seriously, I was like "... More dropshipping? REALLY?!"
We always made them in-house, as it was the only way to be sure you'd get the same pinout everywhere. This was back in the days where connectors wouldn't auto-negotiate tx vs rx, so you had to deal with x-over cables too.
When I worked for an ISP 17 years ago, we also had our in-house splitters...
They even made them fool proof to install, by colouring each contact in the respective wire's colour... you pinned the whole cable to one side, and then went from that side to the other side where the pairs would be switched with a small piece of cable...
That way, we could lead a single cable from the router or modem to where the TV was located, and people had an extra plug for their laptop, or to the office, where both mr and mrs then had a plug to work or play WoW, all without the need for another thing that needed to be plugged into the power network...
Just make it yourself
THANK YOU. In anything remotely modern, this is such a WHY GOD WHY hack.
Even back in the 90s I was able to buy working 10Base-T splitters that properly split the pairs to yield 2 connections. First supplier in mind was BlackBox, supplier of many amazing doohickeys for various types of serial and network connections. Nothing at all new about this stuff.
I even had the occasion to split jacks on a single pull, as you demonstrated. I punched 2 pair into one jack and 2 pair in the other at both ends of a single CAT5 line. Done properly it worked like a charm for 10Base-T and even 100Base-T with enough twists per inch cabling. BlackBox also made wall jacks for this purpose, where all you had to do was punch the wires the same way on both ends as indicated on the jacks' punchdowns. I had a cabler test one of my own such connections with his Fluke, and they both tested okay for 100Mb, but that's not the same as two full connections lighting up all eight wires at once. I'm sure such a contraption wouldn't rate anywhere near good enough for 1Gb, even with great care with the tight pair twists in CAT6e.
In the installations I directed I made damn sure to use professional cablers, good cable, good jacks and blocks, and tested-to-spec 568B connections. I always pulled extra, so need 1 but pull 2, 2 pulls 3, 3 pulls 5, etc. I also only terminated 568B, even for phones. Our phones were 4-wire links, and with either 568A or 568B the 2 center pair tracked for 4-wire phone systems. The jacks we used were also shouldered to properly hold either an RJ45 or RJ11 or RJ14 plugs. We used those lines for Ethernet, telco, and even serial with RTS/CTS and even a few times DTR/DSR...I wired my own RJ45 to DB9 and DB15 connectors for such things so I could use even 568B patch cables for serial printers. Those were the days.
I'm surprised anyone sells such crap as you found. The plans for proper Ethernet splitters are still out there, and aren't even that arcane. I'd be shocked if there weren't already PCB prints ready to go with minimal case requirements.
You could even build a hub or switch into a case of that size, provided it could also pull power from maybe a USB. The trick then would be whether the network switch on the other side permits switches or hubs, which in any business office they SHOULD NOT without an exception process through the networking owner. No secret guest connections.
Actual Ethernet “splitters” do exactly what you did, and split 4 along each line. And I have seen applications where it was the most practical solution, where we had a buried line under asphalt and needed to have two physically separated connections.
Those devices are actually a gold mine for DIY electronics projects (non-ethernet). I recently used a lot of them to split multiple signal wires very cheaply. Ethernet cables are so cheap and they provide 8 wires inside that can be used for anything.. and those devices provide a very nice solution to duplicating the signal
yes, yes, yes. I'm using a few for cat5e carrying balanced audio to several studio monitors.
@@grants7390yup, I’ve used them for studio headphone systems from Furmann.
Like the connections in treadmills
I heard they use them to send HDMI signals even further, you can even get HDMI to Ethernet adapters for this very reason!
I've used them for adding terminators to a cat5 cabled CAN-bus system.
I'm glad you're doing more content like this... Useful to send to my less technically smart family when they ask about junk like this.
They don't want the technical explanation. They just want you to say 'yes it will work' or 'no it will not'. If not, they want you to tell them exactly what to buy instead.
"Make magic box work, me no care how works!"
@@TheSwayzeTrainExactly
@@TheSwayzeTrain i tell this to everyone who asks me for help but really just wants me to fix the issue and not learn about the issue. its so annoying how little people try to understand the world around them
@@Gahlfe123 The reason is that you, me and the rest of us here, we are MUTANTS! We are abnormal :D
@@CMDRSweeper 😅 such a sad reality we have reached an age where trying to understand how things work can make us the weird ones 😢.
While working in the business of networks and telecommunications I can confirm he's right. Those fake splitters had a use back in the days for some connection types, like an analogue telephone line or even ISDN lines. But it's really no use in computer networks. You'll need a real splitter like he described in the video. I also want to comment that it's a good sum up of the topic even for people not having a deep insight in networks. 👍🏼
I did the same in the office I worked at. Boss wanted another computer there, and I was too lazy to pull another cable, and he didn't care, or know anything about cabling ... so two 10cm lengths of CAT5 cut from the roll under my desk, two rj45 plugs, four rj45 sockets, and lots of electrical tape, and I'd made a pair of these in 5 minutes. I was quite proud of thinking up the solution then. Pulling another cable would have taken an hour or half. And this was 20 years ago. Switches and hubs were not that cheap as they are today. And required a trip to the city 20km away. The shopping trip would take me half a day, what with searching for parking, etc. That would cost more than the switch. Plus where were we going to place the switch under the table, and it need another power point, which must never be switched off, or the other computer will go offline. My janky unpowered solution worked problem free the rest of the time I was there, about 10 years. It was light enough, I screwed it to the bottom of the table with just one screw.
2:39 It'll also lower the impedance presented to the headphone amplifier quite significantly if multiple low impedance headphones share a single headphone jack (assuming all headphones are connected in parallel); this could cause the amp's protection circuit to kick in or (if there isn't any protection) damage the amp.
Also importantly it will not decrease the volume which the video says it will. The amp will work harder but unless it fails due to impedance decrease, it won't be quieter. Most headphone amps can support quite a few in my experience.
what if you connect the headphone in series?
@@KarthikeyanDuraivelthinking of how to achieve this…maybe mono works and that will affect volume I believe
@@M_Jaggard pretty much all headphone amps i've seen use protection resistors, or they would burn if:
1) it's not fully plugged and shorts signal to ground
2) jack is detected
3) some music is playing
obviously it will become quieter with resistance in series
A basic splitter should work as a 10/100 Mbps passive hub. I don't see a reason why connection fails altogether. Maybe there is an option in the network adapter settings that enables 10/100 Mbps mode compatibility.
Yup, in the 90s, such splitters were pretty common in many offices.
Mehmed tech tips ftw.
@@carth85 haha 😂
set to half-duplex and collision detection that's baked into the ethernet spec should take care of the rest. LTT didn't show the whole picture with this video.
@@cyberpass thanks for sharing. I guess they didn't mention it because young tech writers have never worked with pre-Gbps Ethernet standards 😀
These are used sometimes in Industrial applications where there are simple analog signals (24v power or maybe a digital IO or a 0-10V analog Signal) running over an RJ-45 connector. Then there are some use cases where these are practical. Like let's say you have an analog pressure signal that needs to be read by 2 different sources simultaneously.
Yup, i used one of the splitters shown 'the more honest one' for splitting analog audio signals being run over structured ethernet cabling. While it was a very special AV use case worked a charm.
Then it's not an Ethernet splitter, it's just an rj-45 splitter
Yep. Worked on a product that ran a RS-485 serial protocol over Cat 5/RJ-45 cables, and these splitters worked fine as all the devices treated the cable as a bus. Typically you'd daisy-chain devices, they'd have two ports that were simply wired together, but splitters worked too.
Was about to comment, that these RJ-45 splitters are used with device, where serial communication like RS485 is run through RJ45, and you daisy chain all for example VFD in circuit. Pretty handy and usefull.
Yep. I see them in pump control panels all the time where the serial coms between VFD units and the HMI use ethernet cables for links.
As an electrician, I've always used (network) switches for connecting devices, however, the splitters work great for use in lighting control devices wired with Cat5E. Send power to a power pack module then Cat5e to a sensor or wall switch or another power pack. Splitters started coming with ceiling occupancy sensors awhile ago making installation easier.
A new thought occurred to me. I have actually used this successfully. I do remember reading that it technically violates the ethernet spec, primarily in that it may introduce crosstalk in very long lines, reducing the 100 meter maximum. In practice, I’ve used it to about 25m. Ad in most hacks, your mileage may vary.
Worked at a company where we used to use splitters back in the start 2000es. At that time 100mbit was the standard and REALLY fast, so splitters were a very useable method to use a single installed cable for two computers. I think we might even have created them ourselves 🙂.
Yup, they were called CAT5 Economisers when 100mbps was top speed and only 2 of the 4 pairs in the cable were used - of course you needed another one on the other end too.
Back when I ran a computer repair business in 2002 I made several of these for my shop. Switches were.... not $8 back in the day....
Yeah, I've also seen them run to two-port jacks on both sides of the cable run.
Years back, we did this for some computers. Sometimes using it for data and phone for a fax/modem on the machine. This was when companies still need to send faxes for legal reasons.
My office used splitter (rarely) to send a analogue phone and ethernet down 1 cable. The splitters we purchased actually split like the one linus made so we could plug one end into the network and the other into the PABX.
Back in the olden days (mid 2000s) we had loads of these in the company server room. We didn't have enough ports in our rack and these were everywhere to allow more low speed devices into the patch panels
If I remember correctly, how they even work properly back then was using something called CSMA/CD
Or Carrier-Sense Multiple Access / Collision Detection
Where it will send data and listen for its own data, if so, data sent successfully, if not and heard something else.
It will pause at random time before trying again.
Wifi now days uses a similar technology, CSMA/CA
Instead of listening to their own data, it first Listen before sending out.
It's why more signal causes slower connection because your WiFi is waiting for that slight moment of silent before transmitting
We use this Y-cables to quickly wire up the CANbus in our machines. It works great for this type of network topology. When you reach the last device on the bus, you can use the second half of the Y-cable to plug a RJ45 connector with a 120 Ohm resistor in.
At 3:10 they forgot to talk about hubs. And about the "The transmission pins on the sending device need to connect to the receiving pins on the other end" part, most network cards allow to switch the RX and TX pins internally automatically (or when did you last use a crossover cable to connect two devices directly together?) 😉
These used to be very common (the correctly wired ones). A lot of older offices were wired up with far less structured cabling than we would do now. Worse yet some of it was probably CW1308 for phones. As more and more devices needed connecting up this became an issue, particularly when IP (and later VOIP) phones became more common. One solution was to use a pair of splitters like this to double up your infrastructure. Yes it was janky but it was also MUCH cheaper than re-wiring a building and didn't disrupt the people working there.
Similar looking devices were also common on digital PBXs which used cat5 cables terminated on RJ45 ends but used entirely proprietary signalling. Some of these would actually have worked with the splitters you bought too because you could set up the live pairs on the PBX and phone so that each phone only used one pair and ignored the rest.
The splitter you constructed is how the legitimate splitters are wired. They would often have a cabling diagram displayed on the top of the splitter. It was useful when things like switches were more expensive or you needed that one extra port in a location without needing a powered device. It's like the Amazon stores have thought 'oh yes, we can replicate that product' without understanding what it's actually doing.
Exactly this. I still find these in Businesses to this day! Either 2 sets of 1,2,3,6 for 2 data connections, or 1 x 1,2,3,6 and 1 x 2,5 (for telephony). With vlanning and gigabit passthrough on newer IP phones, they're a lot less common now.
Never buy from somewhere that doesn't display the wiring diagram, but as Linus eludes to, if you're looking at one of these, there is probably a better solution...
@@andymapp803 I use a pair in my house. Pass Phone/Data from my CPE to the main living room
I've also used legitimate splitters in situations where we needed to preserve vlans and the customer couldn't afford additional in wall runs or more expensive managed switches. Those $8 switches linus showed would strip vlan tags.
I can remember when working in tech support 20 years ago at schools the legitimate ones were used othen as back then switches and even hubs were alot more expensive, t100 was the standard, the only place i saw gigabit lan was between switches
Security installer here...there are versions of this that work. We use them (on each end) to allow 2 IP cameras to be run off '1' wire. (It's obviously two wires from the appropriate ends). As Linus mentioned in the video, you can get 100mbps with splitting. Which is WAY more than you need for a single IP camera. Works great if you need two cameras on a far end of a building, you can run just a single cable for the main trunk.
This!! Works great haha
We used to sell these at radioshack when i worked there. had so many returned because people didnt read that you have to hook it up with 2 into it on each end like the one linus made, and it didnt just simply split them like old jacks. they worked great for the purpose they were built.
Old school telco and network guys did this to run 2 x Cat3 over a single 4-pair cable. Works fine for 100Mbps without PoE, but if you want PoE or 1Gbps then you need more cables.
@@isaackvasager9957 Exactly! There are versions that actually work - It just takes a little know-how! I dare say even PoE Splitters - Done it myself for my security cameras: 2 Cat7 Cables split for 4 PoE Cameras.
Cameras would be a place you like to use PoE so you can run all cameras from the switch UPS.
I used to run a PSTN telephone and an Ethernet connection over a single CAT5 cable between two rooms using a similar splitting technique; 4 wires used for each connection. Worked like a charm.
The only time we used a network splitter was at school with several computers, where we could translate our written programme and copy it over to the roboter. To make sure that that only one computer could get access to one roboter, they used a splitter with a switch to select the current active connection.
Anyways, quite informative eventhough would have guessed so already when I just think about IP's. Honestly didn't think about the DIY method though.
The most stupid thing about these splitters is that the Chinese factory knocking them out could just as easily separate out 2 twisted pairs to each port, as Linus did. It's bizarre that they don't.
It's a design fault with this specific one. We used to buy ones that were like Linus' ones.
Bizarre, yes, but also par for the course these days.
Are you really surprised? TBF the idea is that you get the full connection speed to each device if only one of them is powered on at a time. While that may be useful in some situations it's certainly not how most are being marketed.
@@JJFX-
Wow! Is that the most generous of all possible summaries, or what?
"While that may be useful in some situations it is not how most are being marketed."
What it looks like to me is that the design "team" was probably one guy, who struggled to pass CompTIA Networking, if he could at all, or at that approximate level of understanding, anyway. (Does CompTIA even exist still? Never mind, in either case it's beside the point!) If not a literal uncle, somebody fitting the general description of a nepotism arrangement requested the *intended* function, probably in the very terms of a headphone splitter, probably after seeing an attractive couple (or just a noisy couple) using one on an airplane. The nephew did his best, but reported that it can only work for one device at a time, and didn't know what Linus showed: that instead of connecting all 8 wires (which is what prevents two separate connections working as if they came out of a switch or router), 4 wires can be enough *if* you know which 4 wires to connect and how to connect them. So the "design team" reports to the uncle that it only sorta works, but the uncle owes his sibling or in-law (in other words, one if not both of the nephew's parents) a favor, so he says "that's okay, we'll just put an asterisk and some small print on it. Since the lawyers say that's good enough for our pharmaceutical, food processing, and cosmetics businesses..."
@@reed-young Look, I'm not arguing with you or trying to defend it. I'm beyond tired of all these lazy Chinese resellers trying to cash in on selling crap to people who don't know better. All I'm saying is that splitting the pairs does severely limit bandwidth with the trade-off of allowing two simultaneous connections. Most people would prefer this option but I don't have a problem with the other being marketed correctly.
There are cases one might prefer full speed to one device at a time and it's difficult to run power to a switch. However I'd agree most these sellers are just lazy, incompetent or simply didn't even test the product they're buying for pennies on the dollar.
Properly made splitters have existed for a long time. I've used them and had to make them in some cases to repurpose old building wiring. In some cases, because it was CAT5 (not e) cable wired for phones originally, using a RJ45 to RJ11 adapter was........ fun.
Yeah, just don't buy chinese garbage. There have been splitters out there for decades that work, IF you use them as they are supposed to be used. And ONLY in that case. You don't even need premade splitters, you can use patch panels or etthernetcable connectors to do this yourself. I used this method over 10 years to provide two connections over one cable, since internet connections was far below 100mbit/s anyway.
Im so glad I had a friend who called them "ethernet switches" so when I needed one years later, I didn't search for "splitter".
I remember when cat5 first came out and the company i was working for was going around upgrading people's old coax and one I cant remember with like BNC connectors and even some 25 pin cables in short runs to newer cat 5 setups. The key to the cat5 working is the fact each colored pair is twisted at different rates effectively making each colors run a slightly different length and would have very small but detectable lag time differences as well as resistances. This is how we tested runs were done correctly, the tester ran a timed signal along each line and if it didn't get the pulses in the right timed order then the run was a fail and we needed to pull another line or resolve the issue. Which was typically an end terminal was punched down wrong because for some reason the guy related to the boss who was color blind was allowed to install the wall jacks. (If I'm wrong in this please forgive me, this is how it was explained to me by the bosses nephew that was my partner for many jobs. funny how when it came time to reduce head count the only guy not related to the owner was the first to get canned)
I love that you recall this so vividly. I always grin a little bit when I am terminating any CAT cable, because I know the very act of doing so innately introduces one more point of failure, complexity and latency. 😈
@@LordSirNelson hehe, I have a weird memory, can't remember where I left my keys, important notes for work, but I remember that time I was in the ceiling at Macy's needing to splice cat5 because the guy I was working with didn't listen to me and pulled too short a run then made me climb up in that hot ceiling because I was the newbie to splice that which shouldn't be spliced. That probably connected the 1 bad register that always had issues with the credit card machine LOL.
While you are reminding me of this, and failure points. One failure point using too long a run with cheap routers. cheap router + cheap network card + cheap 1000' cat5 spool = why cant I make a 50' patch cable. lol.
@@Mikej1592Let me guess, also too cheap to even consider at least a partial PoE to give it at least the slightest chance of developing sufficient signal strength to be reliable?
It always amazes me how people love to fuss about their network performance but when you get into it you find that they did things like...IDK, build their antennas too short to ever reach their intended targets (hat-tip salute to #LTT 😉), never run regular systems checks or at least consider routine preventative cabling checks or maintenance.
On the other hand, these same folks also seem to be incapable of keeping their hands off fiber implantations, and are always wondering why their performance is degrading quicker than expected.
“It’s call Entropy and it’s accelerating because you can’t keep your damn dirty paws off the cables and terminals. Ya damn dirty apes.”
So it's very interesting that this is what was taught to you. The wires do have varying lengths and here is the reason why.
When sending electrical signals down a copper wire, it is susceptible to something known as electromagnetic interference. Electromagnetic interference occurs when two electromagnetic fields occupy the same space and then the signals may cross over from one field to the other.
Inside of an ethernet wire, there are several wires and there are electrical currents (and subsequently electrical fields) flowing through each one.
To minimize the amount they talk to each other, manufacturers of etherent cable use 2 techniques.
The first is they twist the cables. The twisting causes the electrical current to shift in polarity on every twist effectively recreating its own signal multiple times over and over again. The second is that they twist them at slightly different rates. This is so the polarity shifts are never perfectly synchronized across the different pairs.
The side effect of twisting the wires at different rates is that the wires are then slightly different lengths
Correct me if I am wrong here, because I am not an electrical engineer, but the manipulation of the wires via twisting creates resistance in a manner that becomes virtually self-regulating for quite some time.
Meaning the intentional asymmetrical twisting makes use of EMI to create resistance throughout the entire cable. No?
If not, then I too could benefit from how there is a functional difference between one philosophy and what is proposed as a different school of thought.
To my layperson understanding, one is simply the more concise explanation featuring the outcome as the focus, while the other focuses on the methodology-while both produce the same outcome.
Did Linus really advertise for a Dropshipping buisness?
I was wondering the same thing. I guess scummy money still pays the bills
If you have any genuine concerns, you can always send a post on the forum, they have a separate section to evaluate their sponsors.
Yes and no... autods is a tool for those running a dropshipping business
who cares, its not like anyone buys from drop shippers anyway
o i muted it, are they the RAID shadow legends of computer hardware?
This is actually build pretty robustly. Shame that all the engineering time went into the case design and non went into electrical design.
Well...They actually do work! Linus is wrong with this video. Collision detection is built into the Ethernet spec. There was a time when you'd buy Hubs instead of Switches.
@@cyberpass i remember playing lan games over an old hub in the early 2010s. Piece of shit barely worked. Still some of the most fun we've had as kids.
@@cyberpass Really? This can work? In that case I have a dumb question - why didn't it on the laptops in the video?
@@cyberpass did you skipped the video or what.. he did said it work.. but with a huge asterisk of "one at a time not at the same time"
@@Nik930714 For this particular one to work, the best option would be one of the devices being on a crossover cable or cables that are already set up for only 4 wire which they do make. I have one sitting on my desk right now that came with my Phillips Hub. They do make legit splitters that do the same as what Linus showed with their homemade one using 4 wires per connection. The problem is with the very poor QA in many places that can't turn around and rip these bad ones apart and fix them, so they sell them off cheap to unsuspecting techno-noobs.
When we built the addition to our house, the electricians offered to run and wire up all our Cat 5 cables drops (about 28 total drops). Their price was reasonable so I showed them where in the utility room I planned to put the patch panel and needed all the cables to be run to. When they told me they had finished, I discovered they had ignored my instructions and had daisy-chained all of the wiring between each drop as if it was telephone cable. They adamantly refused to fix it insisting that this is how they do it every time and no one had ever complained
In the very early 2000s, my family wired up ethernet through the walls in their house, but we didn't put in enough copper for later expansion, so when the day came that we wanted to put two computers in one room, we tried doing this with the single run going to that panel. In theory it should have worked, but when we actually tried it, we found that one machine or the other would link up at 100 full duplex, but the other would consistently connect at only 10 half, and it would flip randomly back and forth if you cycled the connections. I've never been sure whether this was due to the inferior isolation between pairs in CAT5, which I should mention wasn't even the E variant at this time, or if the network cards were using had inferior transceivers, or if we just plain wired it wrong and didn't notice. I had heard at one point that it was a violation of the signal spec, and it makes sense to me that this would produce too much crosstalk between pairs, but that might just be one of those things that doesn't officially work, but in all practical cases does. Certainly, there seem to be plenty of comments from other people suggesting that this used to work reliably for them.
4:32 perfect safety shown by Linus, using a mini circular saw and cutting TOWARDS his hand, and getting about 2cm away from it.
I'm surprised it didn't work tbh. Maybe because of the switch, or maybe windows has disabled csma/cd by default now under the assumption that all ethernet connections are switched nowadays, but once upon a time, home networks used ethernet hubs, not Ethernet switches, and these genuinely did exactly what this splitter here does, only with even more ports
If the ltt crew would manually set link speed to 100mbit/s half duplex in the network adapter settings, then the splitter *should* work out of the box, if the network cards still have csma/cd implemented that is
I'd be surprised if they removed collision detection from their drivers. These should work. I'm surprised LTT didn't mention anything about CSMA/CD.
hubs split packets into individual transmissions, not just wire up everything together
thought the exact same thing. That's prob why they did do it this way cause theoretically you can go up to the "normal" speed the cables offer (1G maybe even 10G)
@@izimsi That's not true at all.
So glad you mentioned the switch because I was like "why wouldn't they just get a switch?"
As a low voltage installer that works with POE T568 equipment...this was a super fun watch!
It was actually kind of shocking to me, earlier in my career (10-20 years ago) how common splitting a CAT5 (or even older) cable in half is in retail environments. Tons of connections at front of house cash registers with the POS on 4-conductor data, often with the other 4 being used for POTS phones. They're still out there being used.
I was thinking the same thing. Used them in supermarkets when I cut my teeth in IT back in the early 2000's. In fact, I still have some of those exact same 20 year old splitters in use in my house today!
I know of a national stock exchange which also used them. There's nothing wrong with their use, if they're use correctly.
We often mixed connections, including 2 wire NEC Dterm phones with the use of these splitters and appropriate wiring on our Krone frames.
Sure and why not? Those applications don't really need a lot of bandwidth so if you can provide connection to several devices with no additional electronics by physically reassigning the conductors, there is little reason not to. This applies even more for analog signals which you can't simply feed into a network switch.
Of course, this assumes they work properly, which the specimens in the video don't.
When I worked for A&T we were allowed to do this because most computers still only had 10/100 cards in them and only used 2 pair of the 4 anyway.
Combined ethernet/phone use is why 10baseT (and then 100baseT) ethernet used 1/2/3/6; it meant two-wire rj11/rj12 needed by phones would naturally fit in the middle of the RJ45 socket and use pins 4/5
Ridiculous that LTT is accepting sponsorships from dropshipping websites now.
@Tajl3r they do decline some sponsorships, in fact a lot of them.
This is actually was done in older environments. At my work, in some of our older horizontal wiring installations are setup this way. the cat 5 wiring uses a Siamese type of wire where 2 of the 4 pairs are separated in their own sleeve but bonded together in parallel. Then, If a particularly area need two ports, each sleeve gets its own connection to the switch. But again, your limited to 100mb on each port. It also can be setup normally where both sleeves are patch together. you will then get gigabyte speeds in that case.
We are slowly trying to phase that type of wiring out of our building(s) the patch panels are too big and bulky
These splitters do make sense if you break it down a certain way. For example, if you deal with gaming and have multiple game consoles, you can theoretically connect 2 devices with the splitter. Since normally you would have one screen and tend to power off the console not being used, the console that is turned on should pick up the internet signal and work. You can buy a switch, a router, or what ever but at the end you have one tv/monitor and only playing with one device at a time.
thing is, a lot of modern devices still run networking when on standby, it'd need a full no-power situation. and if misconfigured to bridge certain connectors, may still fail.
They also make sense as diagrammed. His little test setup may have had a bad product or he bought from a scam company but that doesn't mean there aren't devices out there. There are "splitters" that do split one cable into 2 separate 4 wire connections and both can be active at the same time. You have to have 2 ports on a switch to one splitter and the 2 devices on the other. You will need a pair and they should come as a set if they are legit.
@@jeradw7420 It's neither a scam nor a bad product. It's a splitter for ISDN network, not for ethernet. It's simply the wrong product. What you describe correctly is an ethernet splitter.
Sometimes exact wording is important. Neither "network splitter" nor "RJ45 splitter" means anything. You need to know if it's an ethernet or an ISDN/S0-Bus splitter. Obviously the product in the video is the ISDN/S0 splitter.
@@oleurgast730 He addressed the fact that some of the Network Splitters are somewhat legit (you're still better off buying a switch as they are cheaper, safer, and properly share bandwidth) but the way the one he bought (and many, many others) are advertised say nothing about being ISDN/S0-Bus splitters. They simply claim to be Network Splitters and considering the age of Amazon it's not like these are some ancient product entries built before modern networking standards. Even if they've accidentally created a somewhat legitimate product for really old, niche systems the intent of the sellers is obviously to scam people who don't know any better. Even someone who's fairly knowledgeable about computers could make the mistake of buying a splitter thinking it had some actual logic to it.
Ethernet was actually originally designed for this kind of thing to work just fine!
If you're as old as I am, you may remember seeing computers wired up with 10BASE-2 or 10BASE-5. These older Ethernet physical layers allowed a group of computers to talk over a shared coaxial cable--each computer just taps off the cable at some point or another and they all use CSMA/CD to avoid talking over each other.
With twisted-pair Ethernet (aka every kind of Ethernet we've used since then), however, you need at bare minimum a hub--it's just not electrically designed to be used the same way as the coax flavor. This does come with advantages--it's harder for one fault to bring the whole network down, and each computer can be freely plugged in and unplugged without disturbing the others.
Yep, my first Ethernet experience was with 10base5, connecting some VAX 11/780 computers. I also hand wired some Ethernet controllers, on prototyping boards for Data General Eclipse computers. However, my first LAN experience was in early 1978, on a proprietary Rockwell Collins network, in the Air Canada reservation system.
I have to say, this video confuses me a bit. This is trying to do something that ethernet should be able to do. It's designed to handle collisions.
It demonstrably doesn't work with cat-6 but is this because it's full duplex, or because this particular ethernet cable works differently in some way?
It seems like the documentation for the original splitter is wrong. If they've wired it like described, you'd only want the adapter on one side. A switch like you connected to would likely disable the ports since you effectively connected them directly together. CSMA/CD would effectively mean the client devices are connected to a passive hub like we used to do back in the days of vampire taps. Your link speed would probably negotiate at either 10 or 100 half duplex, and overall performance would drop through the floor depending on how much traffic you were trying to push, but it *should* work. You could even keep branching them out as far as you wanted, but performance would drop for every additional device you added to the tree.
I use an ethernet splitter just like that. With two routers. If one router fails a power contactor fails over and powers up the backup. Pretty slick.
Linus, im so glad you actually made this video. This is something every techie should know as its been around since 2001 and its very handy to know and can solve some very difficult issues for alot of people. For instance, Ive been using this method for many years for an underground cable issue where I have 2 underground cat5e to the garage. My modems are in the garage, which is 300 feet from the house. I have 2 seperate modem connections for 2 seperate networks serving 2 seperate things. That being said I added a pretty large security camera system and I absolutely need all of a gigabit connection and an air gapped network for the nvr in my house. So I have my modem connections to my routers in my house on a single cat5e split to 2 100baset connections. My internet speeds are only 100mb max per anyway so instead of trenching 324 feet for a new cable run I can run everything full speed without trenching.
Why would you do this and not just use a switch to get full gigabit or more?
Auto DS seems sus. Having the word “dropshipping” on your front page is a huge red flag to me
The "DIY" version is also available commercially and has been for years. In times when 100mbit was still pretty much standard I have been using them for Mir than one customer. If you image search for "Delock Rj45 LAN Anschlussverdoppler" you can find a model that shows the wiring on the casing.
These were useful back in the day in datacentres where cables cost a lot of money for low speed connections, or I think E1s (European T1s). Kind of same idea as using bi-di optics these days. Wouldn't use these though :) - I do love the UniFi Switch Flex Mini for these :)
These things you built used to exist. I still have some. They were used in office buildings ages ago to split office ethernet jacks to one jack for your computer, which had 100mbit at the time anyway, and one for your brand new VoIP phone, as landlines were phased out for commercial use.
6:57 "100 Mb is so slow!" as sit here, with 50 mb spread out across 4 family members, 3 of whom are incredibly tech savvy and all need high speed Ethernet
4Mb/s in here if you are lucky and no one is using it. Usually between 2-3Mb/s here.
I really did that almost 20 years ago in my parents house. but I directly connected one cable to a double socket outlet. And it is still in use and works
Here in the uk we have a splitter product from Haydon that also enables POE. I use them for my cctv installations where I need two IP cameras to work from a single Ethernet cable run and they work a treat.
I'm quite familiar with this kind of splitters (the ones Linus built) -- we often used them in the university dormitories in rooms for three people that were only wired for two ethernet jacks. Split it up, boop-a-dee-doo and you've got three for the price of two. Or even four! And since the ethernet was 100 mbps back then anyways, nobody minded at all.
Came to the comments just to post about this. The $50 splitters were also quite a money spinner for the bookstore - and in our case the dorms were wired for single jacks back when it was only expected one person would have a computer. There were even a few switches that were designed for this, 3Com if I recall, where you could configure the odd ports on a switch to carry the signal from the adjacent even port on the switch, so simplify install.
But now a days...$9 switch works better and is cheaper.
I second this. I used splitters like these that actually worked 15-20 years ago. Working ones do exist, although given Amazon's current trajectory, I'm not surprised that scams are so prevalent now.
@@isaackvasager9957 Back in 2010 I literally just used a switch bought for 10 USD used... So yeah lol
@@isaackvasager9957 Not in a university, you have to have port-level logging enabled in the dorms for compliance reasons, at least if the university is following the law, so the only switch allowed would be a university managed one, which are many hundreds of dollars.
For nostalgia and a complete picture:
in Europe similiar splitters were common to split a 4x2pair wire into 100Base Ethernet on pins 1236 and ISDN S0-bus on pins 3456. As ISDN was a bus you also could actually run up tp four devices (i.e. telephones) simultaniously on such "split rivers", but only middle pins 3456 were ever used.
Still seeing some customers who have those horrid splitters in their inventory. Since Fax won't die out entirely in germany, there are still people with genuine 90s Fax machines and these splitters.
@@KR4FTW3RK fax is still commonly used in many parts of the world due to its reliability. it's very common in the medical field, for example, because it's possible to fax data over good old copper wires with less risk of failure (power or internet outages, internal networking failures etc). plus, it allows different organizations and technologies to reliably communicate with each other as it's such a long used method. another factor is that it's very cheap. fax machines are very simple, whereas modern hardware and software can get very pricy. i guess another benefit is ease of use: you just need a number, papers and a machine which can allow for anyone to easily use them without needing training. however it's slowly being phased out these days, mostly due to the burden of needing to redigitize records into more modern internal systems and the costs associated with that
@@kh-ro5su ah yes the thought of billions of medical records being transmitted entirely unencrypted. lovely.
@@KR4FTW3RK yeah it's a weird thing. on one hand it is secure in the sense that it is using phone lines rather than internet. you would essentially need to hijack an existing number - which isn't hard...open up any telephone junction in your neighbourhood, attach some alligator clips, a device and you can listen/make calls like phone phreakers used to do as well as send and receive faxes (though they often need passwords) using a number that isn't yours. it's also far less susceptible to abuse because very few people are going to bother anymore. for example, someone could hijack a fax line and start receiving prescriptions and attempt to fill them at a pharmacy. but despite how long and how much fax has been used in healthcare, you don't really hear of much abuse - mostly because there's very little point. there's not much reason to want some strangers medical records or to risk charges using someone else's prescriptions. it's why despite its insecurity, you rarely hear about abuse. but yeah it's time to pivot away from the technology at this point, it'll just take time due to the complexity of healthcare related information technology
@@kh-ro5su I think fax as a technology is absolutely fine but the implementation with these fax machines is icky to me. I work in IT services and analog fax machines are impossible to troubleshoot from afar. In the days where all the communication a customer does goes via firewalls and managed switches over RJ45 to every workspace, I don't want some analog fax machine sitting in the corner, doing critical work for the customer. Its nonconformity to everything else is a big part of the problem. I'd get a software based fax... there are tons of them.
This video reminds of when I was working in tech support. I had a guy call in who had cut the end off an ethernet cable then soldered it onto a second cable, creating a Y connector. It, of course, didn't work but he insisted it was the router we sent him. I eventually sent him a replacement router to shut him up and, surprise surprise, a new router made no difference and he still was insisting it was our fault.
It has been known from network technicians since the early 90's. Thanks for letting the new ones know.
Linus just found out about the passive ethernet hub (layer one of the OSI model). Keep learning, Linus!
Well...seems like he didn't learn much. Completely ignored the fact that Layer 1 tech was the norm 20 years ago. The ubiquitous WRT54G even used a basic hub.
@@cyberpass Wait, it wasn't a switch? Are you *really* sure?
@@maverickbna I am pretty sure it IS a switch. If I remember from my OpenWRT flashing adventures some years ago.
I was wondering about that if he had only used one and a cross over cable it should have worked out of the box if half duplex is even still supported on consumer grade switches these days.
@maverickbna it was definitely a switch. That's not to say some early home routers didn't have a hub I remember selling one model of GVC that used a hub. However that was before any router supported wifi, in fact that old GVC had a serial port so you could share a dial up connection with an external modem. (It wasn't even configured for fail over, you had to pick, ppp, ppoe, dhcp, or static)
To be clear, whether a signal is analog or digital doesn't influence whether a splitter can work. The deciding factor is whether or not its a two-way protocol. To give an example, the DMX-512 protocol, can be split just fine (in fact passthrough is the basis of the whole protocol). It goes a bit further than that, there are two-way protocols that can be split just fine like phone lines, it all depends on the design of the protocol, whether or not its sequential/serial in nature mostly.
People in the comments pointing out CS/CD is one such protocol.
It's the physical layer that's the issue in this situation which is why you can use a dumb hub and it works fine.
The problem here isn’t even that it’s a two-way protocol. DMX is also a two-way protocol. The difference is that those are engineered to have multiple nodes communicating over the same line and thus can functionally time the data for each fixture (using addresses, universes, etc)
It is indeed a lot more complex. Putting all of it in a comment would have made it convoluted. The main point being that analog vs digital is not really relevant like stated in the video. In fact digital signals can be more suitable for splitting since they are less affected by signal degredation.
Back in the early days of ADSL I had a pair of splitters (and a pile of adapters) to bring both the lan side of the router, and a regular phone line using a single Cat5 from the ground to the third floor of our house. As the ADSL was sub meg speeds back then it all worked a treat. We had a hub but it needed to be on the top floor due to the very old construction of the house and how we had to route the rest of the lan. We only ditched the splitters once the phone line was no longer needed.
Those Amazon splitters are super janky, I can see no purpose for them other than simply to generate e-waste.
I've known and used this "hack" for years.
A fairly recent example is setting up POE security cameras. I had two security cameras going up on the roof, where there wasn't power for well over 100 ft. (30 meters)
Installing POE cameras and splitting the network cable just like this worked great!
This is something I figured out the hard way 20 years ago when I had to figure out a ethernet-based internet solution with one wire for me and little sister's PCs. My ultimate solution was to connect my little sis's PC to mine and get internet that way her for PC. It was slow, but we did manage to play games online at the same time, especially since we went from dial-up to cable modem. Good times.
Yeah I did the same when I was 12, ended up doing modem to my PC then crossover cable to my sister's PC so we could both share dialup 😂
There are actually old proper Ethernet hubs from when switches were more expensive. They were used a lot in industrial applications because they were relatively low bandwidth. They did however use electronic repeaters instead of just tying terminals together. The downside is that without switching there was a lot of packets being destroyed by two devices transmitting at the same time.
Yeah I am actually very confused why this did not work. Ethernet spec has the back off when a device notices other devices talking, so it should actually work with multiple devices (although with worse ping if all devices are talking at the same time)
The technique was called CSMA/CD, but apparently it was deprecated in 2011
Deprecated. Huh. Who knew?
@@shadowpenguin3482 If you set the NICs to half duplex you think it'd still work?
EDIT: ah nevermind, I read the LTT comment. Even if you enforced CSMA/CD the cable is still wired improperly.
Oh yeah, this is exactly what I was thinking, “that’s how the Ethernet spec was supposed to work!!! Y U No Work???” … Deprecated. Seems like that’s something all those sources maybe should’ve mentioned.
I'd love a similar video about power-line adapters for ethernet. Currently running one from my router to my bedroom and don't really seem to notice too much improvement than over wifi other than stability.
Not all splitters are wired wrong. I bought a pair for exactly this purpose and they worked just great.
We even run proper PoE for one of these connections over the splitter (because they use the same wires). Older semi-official PoE uses spare wires and won't work over the splitters.
Dropshipping sponsor ? Wtf
You used to be able to buy splitters wired exactly like the one that you made. I used them a lot in the early 2000's when network switches and hubs were too expensive, and most house wiring only had one cable to each room. Back then everything was 100BaseTX anyway so you weren't losing anything. The brand I used to use had the wiring diagram on a label on the side of the splitter so you could make sure you had the right ones.
i was pretty sure my buddy had a splitter in high school and it worked fine. Glad you commented. This was '04.
I used a couple of such splitters a couple years ago. You can still buy those from reputable electronics shops
I've used these on Schneider VFDs that use a serial/analogue based comms protocol (modbus) and an RJ45 as the connetor. They work pretty well for that application.
I had a Radio Shack splitter. It did work, kind of. When used with 2 devices, if either of them were using network a lot (such as downloading newest Ubuntu), collision will occurs often and the speed will drop a lot. But when there's light traffic, those worked well. I connected 2 networked printer with Radio Shack splitter and didn't have any issue with that splitter.
I was using the 'correct' splitters back in the 90's, the same type you made, they where available from our local trade supply. the newer style of one computer or the other was available too, but pretty useless in a corporate environment. I must of installed at least 1000 of those splitters in places where we where not given enough time to re-run new cables.
07:11 Minor mistake: You recommended the 100 mbps switch for everyone who needs a faster connection than 100 Mbps.
Noticed this too. If the splitter isn't fast enough for moving big files, then neither is a $9 10/100 switch. The Netgear GS305 is $15, just get gig and thank yourself later.
I am obsessed with this topic ever since they had the switch in James bond skyfall in the laptop (when bad guy hacks them). I almost walked out the theater. And the worst is that i never found anybody speaking about it
2:02 The best transition to a sponsor I've ever seen.....
"What the heck is going on here?" We haven't even told you about our Sponsor 🤣
Hey Linus, nice video. Thou I want to clarify that there are in fact many real spliitters on Amazon that are wired just as you hacked your splitter. I work as a electrican in Germany and can tell you that I see those splitters quite often used. Especially if you have one outlet and want to connect a landline phone as well as a printer for example. If you have a bigger infrastructure and don't want any devices which would need extra power, could lower your network security or are a point of failure and you don't need the transfer speed (e.g. phone and printer) it's for sure a valid option (e.g. kwmobile, they even printed the wiring diagram on the connectors)
Thank you! Not everything plugging into an RJ45 jack is using the Ethernet protocol. RJ11 can plug into RJ45. (As can many hobbyist projects.)
When I was about 12 or so, and didn't understand these concepts, I searched for ethernet splitters in order to use my Xbox and PC on the same cable.
Luckily I got one that was setup in the same way as the one you made!
And this was way before anyone worried about any 100mbit connections, so I would never even have noticed the drop in speed. Worked great for my usage!
I know I wouldn’t notice. Speeds here in Jamaica are on average 70mb/s, it’s a good day if we reach 148. So I definitely won’t notice anything wrong with my speeds.
I created this 30 years ago. Used in an switch with MDX (splitting) function. At that times, switches was a God. Only a bunch of Hub's and some switches.
About 20 years ago I was working as a technician running ethernet wires in the multiflat houses(which is vast majority in Russia). It is 40-50 yo buildings with the cable pathways coming from the roof not always in a perfect condition(clogged with existing cables concrete pieces and bird shit usually :). Switches were installed under the roof in the boxes and usually we ran a cable per flat right from a switch. Once i needed to connect 2 flats. I ran 1 ethernet cable with huge effort through the cable pathway and failed to run the second one. Knowing that i don't need all 8 for a single connection i did exactly that - used 4 wires per connection which was more than enough - solid 100Mb between switch and users for both flats. At the time even 10Mb of internet connection was a luxury, some people were sitting on DSL with 256k and 512k still, so 2 meabits over ethernet was great.
If I remember correctly from my CompSci degree, these things (while still useless) should work if you plug in just one, as they function exactly like a hub and thanks to backwards compatibility of ethernet with CSMA/CD (Carrier Sende Multiple Acces with Collision Detection). Have you tested this? This would've been an awesome inclusion in the video.
Yeah I was wondering why it didn't work, maybe the router/NICs don't support CSMA/CD anymore? Hubs used to be pretty common from what I've heard
@@spicybaguette7706 I think it's because they used two dongles and that way the two ports where on the same switch - most switches will shut down the connection in that case.
CSMA/CD is only on half-duplex connections, I had similar "splitters" back in the day and it worked fine for 10Mbit/s half duplex. (but used only a single "splitter")
It's even better: There's a techquickie mentioning Hubs, that tells you that this thing should work like I described: ruclips.net/video/Vc16CCAAz7Q/видео.html
It only works if TX goes to RX of the other plug (with diode) as well as to the TX of the output cable, and RX of output cable is connected to both (also with diode to prevent back feeding from the other port)
This tells the two devices when one is using the cable already
The wiring here is incorrect and doesn't allow this behavior
That "splitter" device might actually work if you set your network ports to half-duplex. Since half-duplex would turn on CSMA/CD, it would be a junction hub. I've not used half-duplex in years, so I'm not 100% sure. But if I remember correctly, it should work.
Also, split pairs have been used for year in telephony. 4 pairs meant that multiple 2-wire or 4-wire analog phones could go down a single Cat5. Made wiring PBX systems to office pods quicker and cheaper. Of course, VOIP made all that obsolete. And I absolutely would not go back, VOIP is superior in almost every way.
Half duplex still used 2 pairs.
I think you are missing one important thing there: For half duplex / CSMA/CD to kick in, you need two devices sending at the same time, to another one that is listening. This involves a bunch of diodes to get wring correct, or an (active) ethernet Hub.
@@jdgmeester Not sure if CSMA/CD would work on differential signals. Old shared-medium ethernet standards used coax and single-ended signals, and these were 10BASE-something. For CSMA/CD to work properly, there is minimum packet length (transmission time) requirement for a cable run of given length, which makes it impractical at higher speeds.
The comments I saw most on-line were from people who claimed they didn’t work and had only bought one of them.
I never understood why they were not always sold as pairs.
Having said that, I work in electronics and I read descriptions. I don’t take anything for granted.
Retrofitting an antique house, I did co-opt the telephone Cat-3 wiring to use one pair for voice, and the other two for RJ-45 for networking… This was well before Gigabit or even 100-T was really a consumer thing. As good as dedicated cat-5? No, but for sharing a single DSL supplied router to the household and peer-to-peer? Just fine, without having to do a few thousand dollars worth of chasing wires through finshed (and ancient lathe-and-plaster) walls in an occupied house.
You have to level it out, so the packets will go 50% left and 50% to the right.
hummm it might work if you reconfigure the microcode on the host. In this case the network switch. BUT!! at that point you are VERY knowledgeable of what you originally bought. haha
if you don't look at the electrons or point a camera onto 'em they actually go left and right simultaniously.
At that point why don't just buy a switch?
You are horrible man!!! 😂
And don't turn it upside down, or all the packets will fall out.
This is one of those things everyone who did networking and phone systems in the 90's and early 2000's knew of and did. The catch was when you encountered someone who had split out the pairs (or worst of all randomly selected wires) in a custom way and you had to test or trace them out. :-(
lesson learned from this pain. Leave notes understandable by the next guy on the inside of the panel or on a label.
Tell me about it! When these were incorrectly wired, split the pairs and then connected to long runs, the error rates reported by the switch were through the roof!
But of course the guy who made it insisted that it was correct, because he tested it with one of those super cheap DC based continuity testers, which cannot find split pair problems because it just tests for continuity and not SNR with balanced AC signals etc. LOL
... cause the next guy's gonna be you. :)
Splitters like you made (1,2,3,6 and 4,5,7,8) had been commercially available pretty much as far back as UTP and T568B has been around. It's the same concept as the 2-line POTS phone splitters that you can still get. It used to be quite commonplace to run one CAT3/5 cable to each desk using pins 1,2,3,6 for ethernet, pins 4,5 for POTS line 1, and pins 7,8 for POTS line 2 in office settings. Although you would usually split out the wires behind the scenes (gangbox in wall, panduit, or cubicle kickplate) to separate registered jacks rather than using a "dongle" like your splitter, but the dongles did exist to perform the combining/splitting.
I have been using this for years. During COVID with 3 kids at home the wifi was toast, but in the living room I only had 1 cat6 cable. So I made a splitter like this, but with 1 phone line and 1 Enet connection for the printer. Works like a champ! Catx cables are great, I've piped surround sound, CATV (yes it works up to channel 35 or so), sprinkler controls, and even 120V!!!!! I've yet figured out how to pump liquids, but have no fear, i'm working on it.....
Of course these bozos who made an actual "splitter" is just crazy. Ahh amazon, thank you!
Um, you know you totally can have passive Ethernet hubs, right?
That box should just be a box of correctly wired diodes.
See, Ethernet contains carrier sense multiple access / collision detecion (CSMA/CD)
All the devices start to notice collisions, discard the data and start using random packet timings to avoid collisions.
Only works in half duplex too, but that might be a function of it being a concentrated network instead of a switched or active network.
The switch in the router is supposed to drop to half duplex. Probably 100baseT too, i don't know about the ones that use the whole pair set
I'm guessing this is a case of everybody on this channel being too young to know about these and the early ethernet standards! 😂
@@MostlyPennyCat yeah... I feel so ancient 😭
So what if I used to wire up 10Base2 wires and passive 10BaseT hubs!!!
Someone in my comment chain (and in other comments too) noticed that they put 2 wires from a switch into the "splitter" (as instructed by the badly written manual), so the switch did its loop detection magic and disabled the ports until the loop was released => no connection. If they had just eschewed one cable on the "router" side, or had plugged that switch directly into that "wall" socket, it would've worked, thanks to the magic of auto-negotiation. While my Mellanox card really does only support 40000baseSR4/Full, 40000baseCR4/Full, 40000baseKX4/Full, 1000baseX/Full, 10000baseCR/Full and 10000baseSR/Full, my intel NIC supports down to 10baseT Half-Duplex through auto-negotiation...
It seems to me that such a splitter *would* be useful for PoE cases where the Ethernet cables are used solely for power. Also, I wouldn't say that splitting doesn't work for Ethernet because of analog vs. digital but because all endpoints for Ethernet are *active* (and not passive like headphones). You'd have similar problems with analog signals if you tried to use a headphone splitter in reverse as an attempt to mix two audio signals; ultimately the problem is that one device is trying to set the voltage of a wire to X while another device is trying to set the voltage on the same wire to Y, making nobody happy.
What's a PoE case?
Well said
@@TheZoraman Path of Exiles build
@@TheZoraman I meant "useful for power-over-Ethernet situations", not "cases" as in physical boxes.
@@jipeh As an avid path of exile player that's all I could read it as lol
Awesome. Good memories! Ya know we used to mess around with this when 5 port switches cost 200 bucks.
A potential clandestine purpose for this device is to be used as a V-Line network tap / passive tap.
Disable one of the blue or brown pins carefully to force the target device to autonegotiate at 100mbps.
Insert the splitter device in-line with the device to be monitored, connect a third machine to the second port of the splitter, force the third device's interface up without an IP address, and manually configure for 100Base-T (no auto-negotiate), set the interface into promiscuous mode, and capture your packets. The goal is to not transmit any packets out the interface on the third machine, but just monitor the network.
Although you may only be able to capture one side of the communication.....
You could even connect it to a small portable Raspberri Pi and connect back wirelessly to the raspberri Pi to capture packets of a device remotely, but now we're really getting into some Mr. Robot territory here.
See, this device may indeed work with three devices connected, and may be quite useful to the right group of people.... so it's perhaps not totally useless.
You can actually passively split 10Base-T connections, but it requires a set of diodes between each port and the trunk. Basically, the diodes cross connect the transmit of each computer to the receiver of the other. And since this is technically a passive hub, the systems have a built in technique that prevents them from talking over each other.
I used to have one that I took all over the country with me as I worked on system installs.
Indeed. Absolute barbaric, abusing the voltage drop trough the diodes to prevent feeding back to your own RX, but still high enough voltage to sense the other two end. Back in the time I've built similar contraption, with using two cards in one machine bridged together to get 4-5 machines in a shared 10Mbps half-duplex network. It was used in multiple lan parties playing Quake and UT. Bunch of soldered wires and splices, looked like a bad sci-fi prop.
@@mtx33 no it doesn't work like that way unless you don't know what you're talking about.
@@mdkhalidhasannahid4148 with all due respect, please read about passive ethernet hub design with anti-parallel diodes. it's working with exactly 3 ports per adapter(obviously not stackable). The signals are not in 10Base-T spec, but still within tolerance. The trick is to create two "rings" with the RX/TX pairs on the positive and the negative side separately with ati-parallel diodes.
The schematic follows A,B,C the computers, equal sign represents the diode pairs. Positive ring (pin 1,3) : =TX+(A) =RX+(B) =TX+(C) =RX+(A) =TX+(B) =RX+(C)= and back to TX+(A)= .
Negative side (pin 2,6): =TX-(A) = RX-(B) =TX-(C) =RX-(A) =TX-(B) =RX-(C)= and back to TX-(A).
There is an excellent video by Clifford Long here in YT ruclips.net/video/FkHuOrr_WNk/видео.html
@@mtx33 not it won't work either. It could be possible in the past. But these connectors aren't wired correctly. The transistor pins of receiver end and source aren't the same lane connection. It won't work in million.
@@mdkhalidhasannahid4148 sure, tell me it didn't worked and i just imagined using it or all the people used the similar adapters. And the linked video is fake too. All 10Base-T compatible card should handle this arrangement.
There are no direct transistor connections in twisted pair ethernet, but Ac coupler/isolating transformers between the negative and positive pairs. The whole purpose of this arrangement to prevent your computer to "hear" itself while sending data (by attenuating the voltage levels smaller than the threshold of the comparators inside the PHY), all the other collisions are handled by CSMA/CD in the spec. Honestly I don't know, why are you still arguing.