# Putting "ends" on CAT-5 Ethernet cable **URL:** \ **Category:** Factual Questions\ **Created:** [March 10, 2008, 2:19am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792 "2008-03-10T02:19:41Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![phungi](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/phungi/32/395_2.png) [@phungi](https://boards.straightdope.com/u/phungi)\ **Post date:** [March 10, 2008, 2:19am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/1 "2008-03-10T02:19:41Z")
I have 50 feet of Ethernet cable to run from a router to a desktop (over a distance of about 25-30 feet in all), but there are no connectors/ends on the cable. I picked up some plastic ends, but am not sure of a few things: 1. Does it matter if the cable remains 50-feet, or should I trim it to 30 feet if that is all I use? 2. Does it matter _which_ wires go in which slot, or it is ok as long as the _same_ wires are matched up at each end? 3. Are there any tools needed other than a wire-cutter/stripper? Do I need a special crimper? Also, any pointers? Thanks! ---
**Author:** ![Shagnasty](https://avatars.discourse-cdn.com/v4/letter/s/9dc877/32.png) [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)\ **Post date:** [March 10, 2008, 2:36am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/2 "2008-03-10T02:36:30Z")
I am not an expert on this stuff but I know a little. You need a crimping tool and the arrangement of the wires is crucial and there are different solutions for different purposes. You can look up the diagrams on-line. It may be cheaper to just by the ready made cable however. ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [March 10, 2008, 2:40am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/3 "2008-03-10T02:40:19Z")
The maximum distance for GigE over cat5 cable is 100 meters, so a 50 foot length should pose no problems. As long as the same wires go in the same slots on both ends, it will work, but there’s no reason not to follow the standard. A color diagram is usually included with the [crimper](http://www.amazon.com/Crimp-Tool-Cat5-RJ45-8pos/dp/B00006B6P0), which you’ll definitely want to get if you want to get the job done in less than a month. ---
**Author:** ![GaryM](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garym/32/241_2.png) [@GaryM](https://boards.straightdope.com/u/GaryM)\ **Post date:** [March 10, 2008, 2:47am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/4 "2008-03-10T02:47:32Z")
Here you [Go](http://images.google.com/imgres?imgurl=http://www.pcman.net/pages/misc/cat5p1.gif&imgrefurl=http://www.pcman.net/pages/misc/cat5.htm&h=589&w=382&sz=80&hl=en&start=3&um=1&tbnid=eEuvkATQawm5AM:&tbnh=135&tbnw=88&prev=/images%3Fq%3Dcat%2B5%2Bwiring%2Bdiagram%26um%3D1%26hl%3Den%26client%3Dfirefox-a%26rls%3Dorg.mozilla:en-US:official) ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [March 10, 2008, 2:47am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/5 "2008-03-10T02:47:33Z")
[QUOTE=friedo] As long as the same wires go in the same slots on both ends, it will work… [/QUOTE] No, it won’t; you also have to make sure you match up the pairs–using the signal from one pair and the return from another totally destroys the benefits of pair twisting. It would be no better than using straight wires. This is probably fine for short runs at low signal speeds, but you couldn’t expect anywhere near the maximum range or bandwidth you could get otherwise. ---
**Author:** ![spinky](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@spinky](https://boards.straightdope.com/u/spinky)\ **Post date:** [March 10, 2008, 3:08am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/6 "2008-03-10T03:08:47Z")
[QUOTE=friedo] As long as the same wires go in the same slots on both ends, it will work. [/QUOTE] This isn’t true. You can arbitrarily switch the pairs around, but you can’t arbitrarily switch individual wires. So for example, the spec calls for the orange pair (solid orange / orange-and-white-dashed) to be first and the brown pair to be last. You can swap these so the brown pair is first and the orange pair is last, so long as you do it on both ends, but you can’t just move one of the wires from a pair to a different position unless you want a very flaky cable. Even at 50 feet, an incorrectly wired cable will be much less resistant to interference and it’s just not worth the randomness it adds to network troubleshooting. So you do have _some_ freedom in the color ordering, but it’s not completely arbitrary. Think in pairs: It’s almost as simple as Aa Bb Cc Dd, except that you swap one of the wires from the middle two pairs: Aa B **c** C **b** Dd. If you’re wiring cables for your personal use and you wire both ends the same, that’s all you’ve got to remember. As **friedo** mentions, if you’re going to the trouble, you may as well do it the standard way, and that standard you’re interested in is EIA-568-B (that’s the one that’s commonly used for regular “straight through” patch cables). Use the second color-coding column from the wiring diagram [here](http://en.wikipedia.org/wiki/TIA/EIA-568-B). The way I remember it is that the striped wire comes first in each pair, the color order is orange-green-blue-brown, and you swap solid blue with solid green. And a handy tip from someone who’s crimped an awful lot of cat 5 cables and seen it done wrong an awful lot too: don’t take off too much sheathing. The plastic part that the crimp tool pushes in should grip the sheathing for strain releif. Also, before you crimp, turn the connector sideways and look to make sure the individual wires have gone all the way to the ends of the little channels that they slide into. Also, expect to screw it up in some undetectable way (other than “it doesn’t work”) about half the time at first. 😉 ETA: when I started writing my short story above, **Q.E.D’s** post wasn’t there, I swear. ---
**Author:** ![DudleyGarrett](https://avatars.discourse-cdn.com/v4/letter/d/d9b06d/32.png) [@DudleyGarrett](https://boards.straightdope.com/u/DudleyGarrett)\ **Post date:** [March 10, 2008, 3:18am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/7 "2008-03-10T03:18:51Z")
[QUOTE=Q.E.D.] No, it won’t; you also have to make sure you match up the pairs–using the signal from one pair and the return from another totally destroys the benefits of pair twisting. It would be no better than using straight wires. This is probably fine for short runs at low signal speeds, but you couldn’t expect anywhere near the maximum range or bandwidth you could get otherwise. [/QUOTE] Actually, it will work fine. You may experience signal loss over long distances (over 100 feet), but for shorter cables it’s fine. Not to mention, that it only matters in Ethernet and Fast Ethernet. Gigabit Ethernet is a whole different animal, and if you notice most store-bought Cat-5E and Cat-6 patch cables are made completely straight-through. The rule of thumb, though, is to make each end of the cable, the exact same, having the RX and TX pair in the same positions on each end. Each end of the cable, should have the following sequence, from left to right: 1. Orange on White 2. White on Orange 3. Green on White 4. Blue on White 5. White on Blue 6. White on Green 7. Brown on White 8. White on Brown. This way, your TX and RX pairs are the same wires (1, 2, 3, 6). Some quick instructions for making the cable: 1. Cut off the plastic cable covering about 2 inches down from the end, so you have 2 inches worth of 8 wires coming out of the end. There should be 4 tight twists. 2. Unravel all the twists (be careful, so cables have a white companion to a colored wire, without any coloring on white cable. If this is the case, you’ll have to keep track of these individually). 3. From left to right, put this cables in the order above, holding them tightly between your index finger and thumb. For every 2 or 3 cables, bend them forcefully so that they are completely flat in your hand. By the time you’re finished, you should be holding 8 very flat wires molded in a row. 4. Once you have a the flat line of cables, cut off about 1.5 inches. If you bent and molded the 8 wires forcefully enough, you should still have a neat row of 8 wires, only now they’re 1/2 long. 5. Slide the RJ-45 over the end so that the Orange on White wire is on the left if you’re looking at the bottom of the connector (the locking tab should be on the other side). Make sure you can see the ends of each individual wire pressed up against the inside of the RJ-45 (you can see this by inspecting the front). 6. Holding everything tightly, crimp, and crimp tightly. ---
**Author:** ![Gorsnak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gorsnak/32/7587_2.png) [@Gorsnak](https://boards.straightdope.com/u/Gorsnak)\ **Post date:** [March 10, 2008, 3:23am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/8 "2008-03-10T03:23:20Z")
5.5 Double-check the wire order before you crimp. That post is almost exactly the same as the post I just deleted on preview. 😛 ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [March 10, 2008, 3:35am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/9 "2008-03-10T03:35:38Z")
[QUOTE=DudleyGarrett] …and if you notice most store-bought Cat-5E and Cat-6 patch cables are made completely straight-through. [/QUOTE] No, they aren’t. All Cat-5, -5E and -6 cables are twisted pair. That’s a major part of what _makes_ them Cat-5, -5E or -6. ---
**Author:** ![DudleyGarrett](https://avatars.discourse-cdn.com/v4/letter/d/d9b06d/32.png) [@DudleyGarrett](https://boards.straightdope.com/u/DudleyGarrett)\ **Post date:** [March 10, 2008, 4:24am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/10 "2008-03-10T04:24:19Z")
[QUOTE=Q.E.D.] No, they aren’t. All Cat-5, -5E and -6 cables are twisted pair. That’s a major part of what _makes_ them Cat-5, -5E or -6. [/QUOTE] Straight-through meaning that, if you look at each end, the wire order is exactly the same. ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [March 10, 2008, 4:25am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/11 "2008-03-10T04:25:46Z")
[CAT 5 Specifications](http://en.wikipedia.org/wiki/Category_5_cable) > [@](#): > > Category 5 > The original specification for category 5 cable was defined in ANSI/TIA/EIA-568-A, with clarification in TSB-95. These documents specified performance characteristics and test requirements for frequencies of up to 100 MHz. > > Category 5 cable includes four twisted pairs in a single cable jacket. This use of balanced lines helps preserve a high signal-to-noise ratio despite interference from both external sources and other pairs (this latter form of interference is called crosstalk). It is most commonly used for 100 Mbit/s networks, such as 100BASE-TX Ethernet, although IEEE 802.3ab defines standards for 1000BASE-T - Gigabit Ethernet over category 5 cable. Cat 5 cable typically has three twists per inch of each twisted pair of 24 gauge copper wires within the cable. [CAT 6 Specifications](http://en.wikipedia.org/wiki/Category_6_cable) > [@](#): > > The cable contains four twisted copper wire pairs, just like earlier copper cable standards. Although Cat-6 is sometimes made with 23 gauge wire, this is not a requirement; the ANSI/TIA-568-B.2-1 specification states the cable may be made with 22 to 24 AWG gauge wire, so long as the cable meets the specified testing standards. When used as a patch cable, Cat-6 is normally terminated in 8P8C modular connectors, often incorrectly referred to as “RJ-45” electrical connectors. Cat-6 connectors are made to higher standards that help reduce noise caused by crosstalk and system noise. Attenuation, NEXT (Near End Crosstalk), and PSNEXT (Power Sum NEXT) are all significantly lower when compared to Cat-5/5e. > > Some Cat-6 cables are too large and may be difficult to attach to 8P8C connectors without a special modular piece and are technically not standard compliant. If components of the various cable standards are intermixed, the performance of the signal path will be limited to that of the lowest category. As with all cables defined by ANSI/TIA/EIA-568-B, the maximum allowed length of a Cat-6 horizontal cable is 100 meters (330 ft) in length, depending upon the ratio of cord length:horizontal cable length. > > The cable is terminated in either the T568A scheme or the T568B scheme. It doesn’t make any difference which is used, as they are both straight through (pin 1 to 1, pin 2 to 2, etc). Mixing T568A-terminated patch cords with T568B-terminated horizontal cables (or the reverse) does not produce pinout problems in a facility. Although it may very slightly degrade signal quality, this effect is marginal and certainly no greater than that produced by mixing cable brands in-channel. The T568B Scheme is by far the most widely used method of terminating patch cables. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [March 10, 2008, 4:26am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/12 "2008-03-10T04:26:07Z")
[QUOTE=Q.E.D.] No, they aren’t. All Cat-5, -5E and -6 cables are twisted pair. That’s a major part of what _makes_ them Cat-5, -5E or -6. [/QUOTE] I think that’s as opposed to cross-over. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [March 10, 2008, 4:33am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/13 "2008-03-10T04:33:40Z")
[QUOTE=DudleyGarrett] Straight-through meaning that, if you look at each end, the wire order is exactly the same. [/QUOTE] But, that’s not what I was talking about that you disagreed with… ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [March 10, 2008, 4:35am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/14 "2008-03-10T04:35:37Z")
You guys are confusing each other and the points at issue are two completely different things “Straight through” has to do with the pin arrangements “Twisted pair” is the internal architecture of how the wire is arranged within the cable sheath See my links & quotes above ---
**Author:** ![mks57](https://avatars.discourse-cdn.com/v4/letter/m/b9bd4f/32.png) [@mks57](https://boards.straightdope.com/u/mks57)\ **Post date:** [March 10, 2008, 5:22am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/15 "2008-03-10T05:22:26Z")
[QUOTE=DudleyGarrett] Actually, it will work fine. You may experience signal loss over long distances (over 100 feet), but for shorter cables it’s fine. Not to mention, that it only matters in Ethernet and Fast Ethernet. Gigabit Ethernet is a whole different animal, and if you notice most store-bought Cat-5E and Cat-6 patch cables are made completely straight-through. [/QUOTE] I did this once, on a 50’ cable, and I can tell you that it did not “work fine”. It was a disaster, not even working reliably at 10 megabit/s. Gigabit Ethernet uses all four twisted pairs, running a 250 megabit/s full-duplex link on each pair. It’s sensitive to shoddy cable and termination. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [March 10, 2008, 8:27am UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/16 "2008-03-10T08:27:22Z")
[QUOTE=ntucker] the color order is orange-green-blue-brown [/QUOTE] Easy way to remember this is to think of it as the outdoors, in order: orange sun blue sky green grass brown dirt ---
**Author:** ![DrCube](https://avatars.discourse-cdn.com/v4/letter/d/a3d4f5/32.png) [@DrCube](https://boards.straightdope.com/u/DrCube)\ **Post date:** [March 10, 2008, 1:00pm UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/17 "2008-03-10T13:00:34Z")
Jeez, guys. You’re going to need the crimpers anyway; just buy the ones that have the standard order written on the side. Problem solved. That way, if you ever want to cut the cable in half and make two 25 foot cables, you don’t have to pull out the magnifying glass and try and remember which order you put the wires in last time. ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [March 10, 2008, 1:43pm UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/18 "2008-03-10T13:43:02Z")
But there are two standard orders, aren’t they? “B” and “A”? And for some reason “B” is always listed first? These two, by the way, differ in which pins correspond to a twisted pair, so that “B” cables don’t have twisted pairs on the same pins as “A” cables. Another thing - how in the world do people get the correct conductor into the correct hole without having a couple of inches of the sheath cut back? People tell me you just have to get practiced at it, but it looks to me like they’re sorting out the pairs and getting everything distributed correctly with just 1/4" of wires sticking out of the sheath. My cables work but they look like they’re wearing hand-me-down pants. ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [March 10, 2008, 1:58pm UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/19 "2008-03-10T13:58:37Z")
If you don’t want to buy tools for one cable, you can get snap connectors that require nothing but a pair of pliers to install. I use ones from Panduit, and they work really well. They also help enforce the Cat-5 standard for length of untwisted sections and such. Basically, you just strip back the sheathing to expose the wires. You lay them on the connector bed, which has color coding to match the wires. Then you put on the top half the connector and squeeze the two halves together. You don’t even have to strip the wires. Panduit wired Cisco’s head office with these things, and they didn’t have a single failure in the bunch (several thousand connections). One other thing - you’re using solid-core wire in an application where it isn’t suggested. Patch cables use stranded wire - this gives them flexibility and the ability to bend repeatedly without cracking the wires. Solid core wire is stiffer, and repeatedly bending it can lead to cracks and flaky cables. Solid core wire is supposed to be used inside walls and properly terminated at wall plates or patch panels, so that once installed they no longer get moved around. The cables that actually go to the computer are stranded wire patch cables. If you just run the solid core wire to the computer, then over time you could be asking for trouble if you move the cables/computer around a bit. ---
**Author:** ![phungi](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/phungi/32/395_2.png) [@phungi](https://boards.straightdope.com/u/phungi)\ **Post date:** [March 10, 2008, 2:46pm UTC](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792/20 "2008-03-10T14:46:54Z")
[QUOTE=Sam Stone] If you don’t want to buy tools for one cable, you can get snap connectors that require nothing but a pair of pliers to install. I use ones from Panduit, and they work really well. They also help enforce the Cat-5 standard for length of untwisted sections and such. Basically, you just strip back the sheathing to expose the wires. You lay them on the connector bed, which has color coding to match the wires. Then you put on the top half the connector and squeeze the two halves together. You don’t even have to strip the wires. Panduit wired Cisco’s head office with these things, and they didn’t have a single failure in the bunch (several thousand connections). [/QUOTE] Is [this the product](http://www.panduit.com/search/product_details.asp?Ntt=modular+plug&N=5000001+3003559+&Nty=1®ion=USA&Ntx=mode+matchallpartial&recName=MPS588%2DC&Nr=P%5FRegion%3AUSA&Ntk=All)? It isn’t easy navigating their web site, but the installation instructions look pretty straight-forward, although they call for a crimper. [Next page](https://boards.straightdope.com/t/putting-ends-on-cat-5-ethernet-cable/440792.md?page=2)