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Handmade vs. Commercially Produced Ethernet Cables
An anonymous reader writes "We have a T1 line coming into our satellite office and we rely fairly heavily on it to transfer large amounts of data over a VPN to the head office across the country. Recently, we decided to upgrade to a 20 Mbit line. Being the lone IT guy here, it fell on me to run cable from the ISP's box to our server room so I went out and bought a spool of Cat6. I mentioned the purchase and the plan to run the cable myself to my boss in head office and in an emailed response he stated that it's next to impossible to create quality cable (ie: cable that will pass a Time Domain Reflectometer test) by hand without expensive dies, special Ethernet jacks and special cable. He even went so far as to say that handmade cable couldn't compare to even the cheapest Belkin cables. I've never once ran into a problem with handmade patch cables. Do you create your own cable or do you bite the bullet and buy it from some place?"
We have TDR equipment and appropriate tools, but we still buy patch cables in bulk. We tested an assortment of ones we had made with cheap crimping tools, and they were all horrible. We can make decent ones, but it takes longer and costs more than buying them pre-tested.
I've spent many hours debugging things that ended up being poor quality TP connectors, but I've also saved countless more hours producing them myself compared to running to the store everytime.
For any permanent installation, go for the molded cables. For anything thats temporary, just pick whatever cable is closest.
And you're not guaranteed to be free of problems just because you buy expensive stuff, I've had problems with Dell PowerEdge switches and factory-made, properly molded STP cables, the RJ45 plug was simply too small and the copper pins didnt connect every time. Really odd, we had to throw away a whole box of STP patch cables for that reason.
Probable impossibilities are to be preferred to improbable possibilities.
Aristotele
I took a network troubleshooting class in college, and we had to test the integrity of data runs that we pulled ourselves and if they weren't good enough we had to do them again till we got our numbers down. I'm sure there are hundreds of data companies that would disagree with you on what it takes to make quality cables and I'm sure "expensive dies" and other nonsense like that really don't help that much when it comes to quality. All you need is a steady hand and lots of practice.
The musings of just another geek and his junk.
Ask him how the premise wiring in every commercial building in the world is installed. They order patch cables from some commercial patch cable vendor for every run, riiiiiiiight.
Also, CAT5e is fine for what you are doing. I agree with the previous poster that you could practically use tin cans and a string for this.
These special dies, jacks, and connectors are called "CAT5" parts and you can buy them at Home Depot I think. Does that make them "special" ?
I promise you I can make more than $20 worth of test-worthy cables in one hour.
I'll second that. I make my own cables when I want a specific length, rather than having the extra wire coiled up in a cable tie.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
Isn't there some diagnostic software you can run to test a cable between two computers?
I guess you may need a special NIC, but even still, its gotta be cheaper than $1200.
$7.95/mo, 200 GB disk, 2TBxfer, MySQL, PHP, RoR.
If you're testing to certify cat5, cat5e, or cat6 you need a cable tester. If you cannot certify the cable to a category you cannot guarantee the cable will work. So the cable is always suspect when you have connectivity issues.
Keep the OSI model in mind, errors at the physical layer cause the whole stack to collapse.
The advantage of cabling over wireless is that you can guarantee that the cable will work where there's no such promise with unlicensed RF spectrum.
There are 3 types of Ethernet cable.
1. Amateur cable. These are done just any old way as long as the colors match at both ends. The pairs don't even have to be twisted for it to work over very short distances (2 to 6 feet) at 1GB.
2. Professional Cable. All the pinouts done properly according to whichever standard you are working with, by someone who knows what he is doing.
3. Factory cables. Here is the dirty secret. Some of these are done by robots and some are just professional cables. There is no way for you to tell which is which.
Now to your specific problem. If your boss insists on paying $300 for $20 worth of cable just to satisfy his own misguided notions of quality, you as the highered help just have to accept his decision and go cry into your beer.
Or better yet. Smile. they had no intention of using the money you would have saved to enhance your salary.
--= Isn't it surprising how badly I spell ?
My opinion is a little different: Don't build them one at a time. And don't buy them one at a time, either.
Just pick up a bunch of different lengths of pre-terminated cable from the good folks at deep-surplus.com. Buy a bunch of 1-foot cables, along with some 3-foot cables. 5-foot cables. 7-foot cables. 12-foot cables. So on, so forth. Then, when you need a cable of a given length, you've (gasp!) already got one!
They're easy to use, too! Just reach up on the shelf, and get one! Way faster than finding the strippers, the cutters, the crimpers, the box of ends, and the box of wire... And then you've still got to cut, strip, sort, cut, insert, and crimp the shit together, before doing the same thing on the other end.
Feh.
They cables from deep-surplus cheap, they're Chinese, they're durable, consistent[1], and I have never had a bad cable after years of doing this whenever possible. Plus, every order comes with a bag of Skittles.
The trick to making this economical and time-efficient is to put it all on one PO.
[1]: Speaking of consistency: I do have the occasional cable that I make myself go wonky, in applications where prefab cabling doesn't apply, like UV-rated Cat5 up a radio tower. This, despite using a good crimper with a good die, and high-quality ends which are made specifically for the wire in question, and a lot of practice to develop decent workmanship. The Chinese cables are consistently more consistent, and always work.
Kid-proof tablet..