USB over Ethernet


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I found this video: 

 

Hack #3 [3:53] seems pretty interesting...  So apparently the reason why I can't use more than 2 USB extension cables on my USB webcam is because USB cable standards are crap, and the signal is pretty much guaranteed to be degraded after 3 meters.  However, Cat5e cable standards are strict, and signals can be reliable up to 100 meters.

 

So if I wanted to use the half a dozen USB webcams I have lying around as security cameras, without having to have a small laptop/RaspPi connected to each one, theoretically all I'd have to do is solder a couple usb-to-ethernet connectors, which literally just solders the 4 usb wires to 4 of the Cat5e wires, and then back to USB on the other end, and in theory, I should be able to use my webcam up to 100m away from my PC (all I really need is 20m though).  

 

Has anyone ever tried this?  I know that you can buy usb-over-ethernet repeaters that also have signal filtering chips on them, and some are even active repeaters that also amplify the signal, but is any of that really necessary to transmit the USB signal 20 meters over Cat5e?

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HAHA no using cat cable won't increase the range.

You can get USB repeaters, from a review someone did on youtube of one (photonvids I think) it basically just supplied +5v at one end so he set it on fire because it was so useless. I think the more expensive ones will work.

 

Unfortunately I had the same idea, to use the RPi and transmit USB video over ethernet using USB/IP but unfortunately the RPi is such a overrated pile of complete ###### it doesn't even send a single frame and crashes.

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I've used these before:

 

http://www.amazon.com/SANOXY%C2%AE-over-Extension-Cable-Adapter/dp/B003BDMK3S/ref=sr_1_1?ie=UTF8&qid=1378422847&sr=8-1&keywords=USB+Extender+with+Cat5

 

They worked reasonably well, but RJ45 connections are not the best for something that moves around such as these adapters.  In applications where I was able to secure the adapter so that a user couldn't move it I've had a lot of success.  Where they were not secure I've had complaints about losing the connection to my hardware and messing up other USB devices.  Its just...not the best connection apparently.  Gotta get a little creative with the strain relief.

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HAHA no using cat cable won't increase the range.

CAT5 will increase the range.  I've used several USB to CAT5 adapters to run SMARTboards about 50' and they work fine.

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I'm sure in some instances it will work just fine.  But the reason 100' USB cables aren't sold (or maybe not common is the better word), is because most USB devices would not work properly with that length of cable.

 

If you try and it works fine for your application, I say go with it.  But if your goal was to start manufacturing 100' USB cables and selling them, get ready for a lot of returned cables.

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HAHA no using cat cable won't increase the range.

You can get USB repeaters, from a review someone did on youtube of one (photonvids I think) it basically just supplied +5v at one end so he set it on fire because it was so useless. I think the more expensive ones will work.

 

Unfortunately I had the same idea, to use the RPi and transmit USB video over ethernet using USB/IP but unfortunately the RPi is such a overrated pile of complete **** it doesn't even send a single frame and crashes.

 

Why you laugh?  It's already been well established that using cat cable will increase the range.  The question is whether or not you also need an amplifier and noise filter, which is what most usb-ethernet repeaters include.

 

There is a LOT wrong with that video.

...such as?  I did notice they keep calling an 8P8C connector an "RJ45" connector, when the connector has absolutely nothing to do with RJ45.  But I didn't see anything else wrong with the video...

 

I've used these before:

 

http://www.amazon.com/SANOXY%C2%AE-over-Extension-Cable-Adapter/dp/B003BDMK3S/ref=sr_1_1?ie=UTF8&qid=1378422847&sr=8-1&keywords=USB+Extender+with+Cat5

 

They worked reasonably well, but RJ45 connections are not the best for something that moves around such as these adapters.  In applications where I was able to secure the adapter so that a user couldn't move it I've had a lot of success.  Where they were not secure I've had complaints about losing the connection to my hardware and messing up other USB devices.  Its just...not the best connection apparently.  Gotta get a little creative with the strain relief.

Right, those are the things I've seen, they usually have a noise filter in them, and the ones that also require an external power adapter to work also have a signal amplifier in them.  I'm wondering if you need either of those, if you don't want the full 100m range, but you want more than 3m range.

 

...and its not an RJ45 connector.

 

 

I'm sure in some instances it will work just fine.  But the reason 100' USB cables aren't sold (or maybe not common is the better word), is because most USB devices would not work properly with that length of cable.

 

If you try and it works fine for your application, I say go with it.  But if your goal was to start manufacturing 100' USB cables and selling them, get ready for a lot of returned cables.

The reason 100' USB cables are not sold is because the USB cable standards do not allow for the signal to last more than 3 meters or so.  Cat5e cable standards do.  My goal is not to manufacture these, I just... wait, I already said what my goal is.  I'm not typing all that out again! :p

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Using CAT cable does not increase the range by any margin you can measure.

If you somehow do happen to find conclusive proof of a theory that completely defies physics, please feel free to paste a link to it here.

 

(And submerging a cable in liquid nitrogen to make it superconductive doesn't count)

 

 

The reason 100' USB cables are not sold is because the USB cable standards do not allow for the signal to last more than 3 meters or so.  Cat5e cable standards do.  My goal is not to manufacture these, I just... wait, I already said what my goal is.  I'm not typing all that out again! :p

 

Shaking my head. It's got nothing to do with the cable itself, it's to do with how the system works. Do you not think that if you could increase USB range to 100m using CAT cable that intel wouldn't have just dropped the USB cable specs and use a CAT cable? No, because it's a load of crap.

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Why you laugh?  It's already been well established that using cat cable will increase the range.  The question is whether or not you also need an amplifier and noise filter, which is what most usb-ethernet repeaters include.

 

...such as?  I did notice they keep calling an 8P8C connector an "RJ45" connector, when the connector has absolutely nothing to do with RJ45.  But I didn't see anything else wrong with the video...

 

Right, those are the things I've seen, they usually have a noise filter in them, and the ones that also require an external power adapter to work also have a signal amplifier in them.  I'm wondering if you need either of those, if you don't want the full 100m range, but you want more than 3m range.

 

...and its not an RJ45 connector.

 

 

The reason 100' USB cables are not sold is because the USB cable standards do not allow for the signal to last more than 3 meters or so.  Cat5e cable standards do.  My goal is not to manufacture these, I just... wait, I already said what my goal is.  I'm not typing all that out again! :p

 

The ones I have use RJ45 connectors.  RJ45 is the most common connector used with cat5 to make a standard ethernet cable.  Thats what these USB extenders user.  Standard ethernet cables.  My connection problems are with the poor female RJ45 port on these.

 

I keep my shop stocked with RJ45 connectors.  I know what an RJ45 connector is.

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I've tried USB over Ethernet solutions in the past without too much success. I used to know someone who's company used CAT5E with purpose built webcams & equipment for security & they worked very well (Over 60M and on steel floodlight poles).

Your mileage will vary greatly depending on the how many milliamps the USB device requires, length of cable, solid copper core (non-CCA) and latency tolerance of the device. I had an IrDA USB dongle that worked over 20M but for a USB HDD, I couldn't get it to work >6M. Cable grade was solid core CAT5 at the time.

 

I do run HDMI @1080p / 60Hz over 2x29M of outdoor grade CAT5E via 5v extender with great success though.

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powered usb extenders are much better, but they are much more expensive, some going into the $500 range.  Again, cheaper to buy the right equipment instead of making the wrong equipment work.

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The ones I have use RJ45 connectors.  RJ45 is the most common connector used with cat5 to make a standard ethernet cable.  Thats what these USB extenders user.  Standard ethernet cables.  My connection problems are with the poor female RJ45 port on these.

 

I keep my shop stocked with RJ45 connectors.  I know what an RJ45 connector is.

 

Let me quote from the wiki:

 

 "8P8C modular connector type is often called RJ45 because the Registered Jack standard of that name was an early user of 8P8C modular connectors. A very? popular use of 8P8C today is Ethernet over twisted pair, and that may be the most well known context in which the name RJ45 is known, even though it has nothing to do with the RJ45 standard." - teh wikease.

 

So in the official, documented context, RJ45 is a user of the 8P8C connector.  But there is no such thing as an RJ45 connector.

 

In the real world, however, you're right, so many people started to call an 8P8C connector an "RJ45 connector", that following the rules of how words are defined by the most commonly used definition, "8P8C" connectors have become to be known as "RJ45 connectors".

 

But in the nit-picky, official sense, it isn't, and never has been.

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you are using cheap low quality cables then because i have a webcam that has 3 extension cables and it runs fine

 

I said 3 meters of extension cables, not 3 extension cables.  And yes, you're right, I've found the quality of cables you can get to vary hugely.  I've bought all my current USB Extension cables from dollar stores (because I was a firm believer in getting the cheapest cable possible, because I had no idea that "quality cables" wasn't just snake oil); some of them were properly shielded, with the shielding properly connected to the ground wire and the metal casing of the plug, and the data lines in a twisted pair... and some of them had absolutely no shielding, and didn't even bother to twist the data pair.

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Let me quote from the wiki:

 

 "8P8C modular connector type is often called RJ45 because the Registered Jack standard of that name was an early user of 8P8C modular connectors. A very? popular use of 8P8C today is Ethernet over twisted pair, and that may be the most well known context in which the name RJ45 is known, even though it has nothing to do with the RJ45 standard." - teh wikease.

 

So in the official, documented context, RJ45 is a user of the 8P8C connector.  But there is no such thing as an RJ45 connector.

 

In the real world, however, you're right, so many people started to call an 8P8C connector an "RJ45 connector", that following the rules of how words are defined by the most commonly used definition, "8P8C" connectors have become to be known as "RJ45 connectors".

 

But in the nit-picky, official sense, it isn't, and never has been.

 

Well, thats a whole new level of anal that I'm not familiar with.  Its like you are correcting someone for calling PTFE, Teflon.  If you do any search on any electric and electronic parts distributor (say AlliedElectronics) for RJ45, you will find what you are looking for.  In fact, more so than if you type in "8P8C".  But, w/e.  The wikipedia gods have spoken and they are never incorrect.

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moeburn, on 06 Sept 2013 - 09:15, said:moeburn, on 06 Sept 2013 - 09:15, said:

I said 3 meters of extension cables, not 3 extension cables.  And yes, you're right, I've found the quality of cables you can get to vary hugely.  I've bought all my current USB Extension cables from dollar stores (because I was a firm believer in getting the cheapest cable possible, because I had no idea that "quality cables" wasn't just snake oil); some of them were properly shielded, with the shielding properly connected to the ground wire and the metal casing of the plug, and the data lines in a twisted pair... and some of them had absolutely no shielding, and didn't even bother to twist the data pair.

and 3 meters is about ten feet right? my extensions are 3 feet plus the foot or two of the webcam cable

 

you should be able to go up to 5meters ref http://www.usb.org/about/faq/ans5

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and 3 meters is about ten feet right? my extensions are 3 feet plus the foot or two of the webcam cable

 

you should be able to go up to 5meters ref http://www.usb.org/about/faq/ans5

 

That link is dead.

 

USB will only work a max of 15 feet or 5 meters.  3 meters is all you want an extension cable to be.

Okay, let's clear all this up:

The data cables for USB 1.x and USB 2.x use a twisted pair to reduce noise and crosstalk. USB 3.0 cables contain twice as many wires as USB 2.x to support SuperSpeed data transmission, and are thus larger in diameter.[50]

The USB 1.1 Standard specifies that a standard cable can have a maximum length of 3 meters with devices operating at Low Speed (1.5 Mbit/s), and a maximum length of 5 meters with devices operating at Full Speed 12 Mbit/s.[citation needed]

USB 2.0 provides for a maximum cable length of 5 meters for devices running at Hi Speed (480 Mbit/s). The primary reason for this limit is the maximum allowed round-trip delay of about 1.5 ?s. If USB host commands are unanswered by the USB device within the allowed time, the host considers the command lost. When adding USB device response time, delays from the maximum number of hubs added to the delays from connecting cables, the maximum acceptable delay per cable amounts to 26 ns.[51] The USB 2.0 specification requires that cable delay be less than 5.2 ns per meter (192 000 km/s, which is close to the maximum achievable transmission speed for standard copper wire).

The USB 3.0 standard does not directly specify a maximum cable length, requiring only that all cables meet an electrical specification: for copper cabling with AWG 26 wires the maximum practical length is 3 meters

- Teh Wikease

However, I have seen companies that sell nothing but USB extension cables, and they explicitly state that their very long, 15ft cable is ONLY for USB 1.1.

In my personal experience, I have a 5ft cable and a 3ft cable.  My webcams (each also with a 5ft cable) work fine on both individually, but not when combined for 13ft.  However, I discovered that if I put my powered USB hub in between the two, I can successfully get 14ft between the computer's USB port and the webcam (14ft not 13 because the USB hub's cable adds an extra foot).  This is because the chip that muxes the four incoming signals together also amplifies them, so in terms of cable length/signal strength, its as if the webcam was only an inch away from the hub, even though it is actually 10 feet away from it.

There's this bit talking about POWER over ethernet, and how ethernet cables and interfaces are commonly used instead of USB cables and interfaces on things like security cameras, simply because the power can travel futher, even though the security camera would work fine with either USB or ethernet:

The IEEE 802.3af Power over Ethernet (PoE) standard specifies a more elaborate power negotiation scheme than powered USB. It operates at 48 V DC and can supply more power (up to 12.95 W, PoE+ 25.5 W) over a cable up to 100 meters compared to USB 2.0, which provides 2.5 W with a maximum cable length of 5 meters. This has made PoE popular for VoIP telephones, security cameraswireless access points and other networked devices within buildings. However, USB is cheaper than PoE provided that the distance is short, and power demand is low.

Ethernet standards require electrical isolation between the networked device (computer, phone, etc.) and the network cable up to 1500 V AC or 2250 V DC for 60 seconds.[98] USB has no such requirement as it was designed for peripherals closely associated with a host computer, and in fact it connects the peripheral and host grounds. This gives Ethernet a significant safety advantage over USB with peripherals such as cable and DSL modems connected to external wiring that can assume hazardous voltages under certain fault conditions.[99]

Granted, that is for power, not data, but the theory still holds true.

 

The wiki page also states that the limiting factor in a USB cable length is the AWG of the copper wire, which is almost always 26-AWG.  Ethernet Cat5 uses the thicker 24-AWG.  I have no idea what AWG Cat5e and Cat6 use.

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Q2: Why can't I use a cable longer than 3 or 5m?
A2: USB's electrical design doesn't allow it. When USB was designed, a decision was made to handle the propagation of electromagnetic fields on USB data lines in a way that limited the maximum length of a USB cable to something in the range of 4m. This method has a number of advantages and, since USB is intended for a desktop environment, the range limitations were deemed acceptable. If you're familiar with transmission line theory and want more detail on this topic, take a look at the USB signals section of the developers FAQ.

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So you're talking about one of these? http://dx.com/p/usb-2-0-3-port-hub-with-rj45-ethernet-network-lan-adapter-20cm-cable-51436

 

Think they work great. You can have up to 3 USB devices (8 cores in ethernet, so two data per USB connection and your shared 5V and GND) Or you can opt to only do 2 USB connections and do PoE if you need something like 12V at the other end.. Careful with PoE and many USB data lines that theres no cross-talk (keep runs short or employ some filters). Cat6 may be a better option as each twisted pair is segregated. Suggest using stranded core CAT cabling for this, solid core is hard to work with.

 

You can also save the $12 and build one yourself pretty easily.. They are direct connect cabling from your USB to your ethernet lines...

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*snip*

 

The wiki page also states that the limiting factor in a USB cable length is the AWG of the copper wire, which is almost always 26-AWG.  Ethernet Cat5 uses the thicker 24-AWG.  I have no idea what AWG Cat5e and Cat6 use.

You are great at spitting out stuff posted on sites, but can't be bothered with picking up a cable and looking at it...surely you have a cat5e laying around...I have a few thousand around me.  I was able to look, I can even take a picture, but being that you have this thing with trying to prove me right, I will let you continue.

 

I don't think that the limiting factor of a usb cable is the AWG of the copper wire.  I am pretty sure it has to do with the power and timing of the signal which is why you would need repeaters to be able to extend the line (they make powered repeaters, powered usb hubs can be used as repeaters).

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