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Ethernet cabling has been standard in networking installation for years. It’s the fastest way of connecting PCs together — to your router, or a central switch. Sure, you could go wireless for convenience, but the truth is that wireless connections will always be slower, and are particularly susceptible to interference. A good network cable can go for 100m or more at gigabit speeds. (Although, if you insist on Wi-Fi, we’ve got some tips to help maximise your connection Wireless Feng Shui: How to Optimize Your House For Best Wi-Fi Reception Wireless Feng Shui: How to Optimize Your House For Best Wi-Fi Reception Setting up a Wi-Fi network should be an easy prospect, shouldn't it? I mean, a house is a closed-in box, and you'd think when you place a device that transmits wireless signals in all directions... Read More , and our pick of Wi-Fi extenders The Best Wi-Fi Extenders: Which One Is Right For You? The Best Wi-Fi Extenders: Which One Is Right For You? What are the best Wi-Fi extenders out there? We've rounded up three of the best performing, cheapest, and best value wi-fi extenders for 2016. But which one is right for you? Read More ).

We’ve showed you before how to make your own straight-through Ethernet cabling How To Make Your Own Ethernet Cables How To Make Your Own Ethernet Cables Read More . The article may be old, but it’s still as relevant today as ever. However, we’ve never described how to make a cross-over cable. If you’re interested in learning more about networking in general, we have a complete Beginner’s Guide to Home Networks you should take a look at first.

What Is Cross-Over Cable?

In a Ethernet networking environment — like in a family home with multiple PCs that are wired — the computers must all connect to a central router. The router takes all the bits being sent out by the computers and relays them onto the other devices on the network, or out to the wider internet. However, a crossover cable can be used to connect two devices directly, without the need for a router in the middle.

It simply reverses some of the pins so that the output on one computer is being sent to the input of another. Some of us have fond memories of using a cross-over cable to play multiplayer games before the internet was a thing.

Connecting two machines is one use for a cross-over cable; the other is to expand a network by connecting another network switch, thereby giving you more ports. It’s always handy to have a length of cross-over cable around! Or is it?

Why You Probably Don’t Need A Cross-Over Cable

Having explained how a cross-over cable can be used, you ought to know that you probably don’t need one. Most network devices are now equipped with what’s called “autosensing”, or switchable “uplink” ports. These either use software to automatically detect when a port should be run in cross-over mode, or give you a physical switch that you can use to enable the mode. They do the pin cross-over in the switch hardware itself.

Realistically, you’ll only really need a cross-over cable if you’re dealing with very old hardware (like a hub What's the Difference Between Routers, Hubs, and Switches? What's the Difference Between Routers, Hubs, and Switches? Are you confused about the differences between a hub, a switch, and a router? Don't worry. The answer is actually quite simple. In this article, we break it down for you. Read More ), or if you’re wanting to quickly connect two computers in a network-less environment.

Even then, nearly all modern hardware will automatically detect what you’re trying to do and configure the Ethernet port appropriately, without the need for a cross-over cable.

What You’ll Need

network cable wiring

  • Some Ethernet cabling, obviously. I’ll be using CAT5 today. Strictly speaking, CAT5e is certified for true gigabit support, but in practice plain old CAT5 cabling can be used just fine over short distances.
  • A crimping tool. This your all-in-one networking tool – specially shaped for pushing down the pins in the plug and able to strip the shielding off cables, as well as cut.
  • 2 RJ45 plugs.
  • (Optional) 2 plug shields.

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In addition to these tools, you’ll also need the diagram below, preferably printed out as a reference. Note that side A and B are not simply inverted:

crossover cable wiring

Making The Cable

Start by threading some shields onto the cable, it will be easier to do it now rather than later.

crossover cable wiring

Strip about 1.5cm of cable shielding from both ends. Your crimping tool should have a round area specifically for this task.

crossover cable wiring

Untangle the wires (there should be 4 “twisted pairs”). Arrange them in the order shown on the sheet from top to bottom; one end should be in arrangement A, the other B.

cross over cable

When you’ve got the order correct, bunch them together in a line. If you have some that stick up beyond the others, snip them back to a uniform level.

The hardest part is placing these into the RJ45 plug without messing up the order. Hold the plug with the clip side facing away from you; the gold pins should be facing towards you, as shown below.

cross over cable

Push the cable right in — the notch at the end of the plug should just be over the cable shielding. If it isn’t, you stripped too much shielding off. Snip the cables back a little more.

network cable wiring

When the wires are sitting tightly in the plug, insert it into the crimping tool and push down. In theory the crimper is shaped to the exact right size, but in practice I find pushing too hard can crack the brittle plastic plug.

Repeat for the other end, using diagram B instead.

If you don’t have a cable tester, the easiest way to test is just to plug it in. Try connecting two computers directly together. The status LEDs vary by device, but typically one will show activity while the other indicates speed.

Let us know in the comments what it is that you needed a cross-over cable for!

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  1. manisha
    February 4, 2017 at 7:02 am

    why the only white color is added in between the orange,green &brown why not any other color .
    is there any specific meaning of that or not ?

    • James Bruce
      February 5, 2017 at 9:18 am

      It's not white – it's white/other color. They're 4 twisted pairs, so each color has a corresponding ground cable, twisted together to remove interference.

  2. Rob Tully
    October 5, 2016 at 4:13 pm

    Most articles I have read only reverse the orange and green pairs, (recieve and transmit pairs).... the Blue and Brown pairs stay put. Why do you reverse them as well? Pins 4,5 and 7,8 are not used (except in PoE systems, and in those it would be important that green and brown pairs stay straight through) Im not a pro, but I think there is an error here.

    • James Bruce
      October 5, 2016 at 4:20 pm

      Gigabit Ethernet uses all four pairs.

  3. Troy
    August 6, 2016 at 1:45 am

    That termination in your photo is still not very good. The jacket should be past the crimp bar, and the crimp bar comes down onto all of the untwisted pairs... That bar's purpose is to avoid tension on the cable from pulling on the wires that the pins crimp down onto.

  4. Anonymous
    September 8, 2015 at 8:03 pm

    Hello,

    I just wanted to take the time to let you know that your wiring diagram, and your explanation proved essential in completing my rewiring project. Thank you for taking the time to create this guide!

  5. Anonymous
    June 14, 2015 at 6:32 pm

    thanks,

  6. prem
    November 9, 2012 at 3:26 pm

    i like for cable standard

  7. tim dancun
    August 22, 2012 at 6:24 am

    wat i can say is dat it works,i tryed then it works...thanx 4 da help

  8. Dany Bouffard
    July 9, 2012 at 3:16 pm

    I have done a lot of cable, normal and crossover and depending on the quality of cable the straightening of the cable is more or less difficult to obtain a good result. But its one of the most crutial part of making the cable.

  9. Izz...
    July 9, 2012 at 11:53 am

    Wow! Thank you so much for this information! I have always wanted to learn how to make an ethernet crossover cable :)

    I've seen a man at the shop doing it but I don't really get the idea of how..This is very helpful :)

    Thank you again..

  10. ferdinan Sitohang
    July 9, 2012 at 2:14 am

    For the enhancement of the technology peripherals, nowadays, cross over cable can be handle with the straight one. But this old fashion cable is still necessary for some reasons.

    • toby
      September 21, 2012 at 10:49 pm

      what are those reasons? i never cross cable anymore

  11. Simon Slangen
    July 8, 2012 at 10:50 pm

    I know it's old fashioned, but I still use a crossover cable to move large files between computers. With two SSD drives, it's just so fast!