Handmade vs. Commercially Produced Ethernet Cables 837
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?"
How much is your time worth (Score:5, Insightful)
Re:How much is your time worth (Score:5, Informative)
While it may be cost effective to crimp and cut your own cable when you are making less than 20 dollars an hour once you are making 20 dollar+ just buy it.
I promise you I can make more than $20 worth of test-worthy cables in one hour.
Comment removed (Score:5, Interesting)
Re:How much is your time worth (Score:5, Funny)
Yeah,
But the occasional dud-job does pass by. Then you've got this thing spraying ether all over the walls, the floors, and what-have-you.
Try explaining that one, passing the hallway, with ether dripping from the front of one''s trousers. "It's my handworked cable, you see..." you might mumble to colleagues, to their dubious glances.
I know a lot of you came up while 10 MbPS was standard. The drizzling or atomizing was even comforting - almost acceptable in Cat5. Now, 100 MbPS goes off like a water-cannon. With Gig arriving to the desktop and commodity rack, I don't know if "grow-your-own" is advice that one may any longer advocate with a dry lap or chin!
Re:How much is your time worth (Score:5, Interesting)
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.
Re:How much is your time worth (Score:5, Insightful)
Re:How much is your time worth (Score:5, Funny)
Re:How much is your time worth (Score:5, Informative)
Orange and white, Orange. Green and White, Blue. Blue and White, Green. Brown and White, Brown.
Use pieces (cable, plugs, jacks) certified for the speed you want to carry.
Once you get those two down, understand not to untwist more of the cable than absolutely necessary to get it into the connector, get it correctly into the cable, and get a good solid crimp on it - and TEST IT after you crimp both ends - odds are it's more than sufficient to carry as much GigE traffic as you care to move.
Once you have a stock of pieces on the shelf, it's WAY more cost effective from an employers perspective to make a single cable than to sit down, fill out a purchase order, have that purchase order pass through several hands during processing, follow up with the paper order, wait a week to have that single cable shipped to you. ESPECIALLY if that cable is a statistical anomaly and needs to be replaced.
If you're wiring a patch panel for the first time, however, order a hundred or so cables of various length and save yourself the hassle.
Re:How much is your time worth (Score:4, Insightful)
If you're wiring a patch panel for the first time, however, order a hundred or so cables of various length and save yourself the hassle.
... or hire an unpaid summer intern from a local high school who wants some experience in the IT biz. Lets be honest here. Its people can't find jobs right now, and if the kids is even remotely interested in IT, he will choose pulling cable through your dusty attic over flipping burgers any day.
Re:How much is your time worth (Score:5, Insightful)
The real acid test would be to get one of these TDR units, buy 10 cables from each of two or three reputable companies and compare it to the results from 10 cables done in-house.
All this talk without an objective stress test is pretty pointless.
Re:How much is your time worth (Score:5, Interesting)
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.
Re:How much is your time worth (Score:5, Funny)
Orange and white, Orange. Green and White, Blue. Blue and White, Green. Brown and White, Brown.
Just Remember: OverWeight Olga Gives Willingly, But Betty White Gives Bitchin'-Wild Blowjobs.
Re:How much is your time worth (Score:5, Insightful)
Make one long cable of the total length of all of the cables you want, and terminate the two ends and test the cable. Then, you know those two ends are good. Then, for your first "finished" cable, snip off the length you want, and terminate the snipped end. Then, test the cable. If it fails, you know which end needs fixing.
Then, with the remaining slightly-less-long cable, terminate the snipped end of that, and test. Then, snip off the next length you need, etc...
I used to just pull off the length I needed from a spool, crimp the two ends, and test. But, if the cable failed the test, and I couldn't see where the problem was, I'd have to flip a coin to decide which end to re-do first. The above method avoids the coin flip. You'll know which end you have to re-do.
Re:How much is your time worth (Score:4, Informative)
Re:How much is your time worth (Score:5, Insightful)
But are they exactly the right length to pull from A to B, or do you have some coiled up uglies?
A forward thinking IT professional knows to leave some slack in the cables, otherwise plate tectonics makes fools of us all.
Re: (Score:3, Informative)
I never ever make my own cables for long-term PC connection patch cables, only for patch panelswitch connections and cross-overs.
I wired all of my own in-wall cabling at home, but I pay others to do it for work (just for time reasons).
I always use packaged stranded copper patch cables for connecting PCs to wall jacks though, as they're more flexible and resilient to breakage when twisted or bent repeatedly. Solid core cables will snap or degrade rapidly if bent repeatedly or at sharp angles.
Re: (Score:3, Funny)
um... the commercially cut cables are made of certain length for a reason. If you've taken physics especially emf harmonics, you'd know wanting a specific length without considering harmonics is all kinds of bad because it may result in emi emission, or even worse, cross talk. This happens to twisted pair as well as coaxial due to energy absorption of the copper cable themselves (part of the energy in the inner cable gets converted to heat for coax and heat conversion not equalizing for twisted pair, emf wi
Re:How much is your time worth (Score:5, Informative)
I can't agree with this - if the termination of a transmission line is correct at each end, then the length has no matter at all for any frequency (in theory, not accounting for increasing losses with frequency, but then there's a reason for length restrictions in the CatX/Ethernet standards).
If you're talking about a *tuned* line (eg a stub or a tuned antenna feeder), then length is important. But we're not. If you've got problems with harmonics or matching and reflections then your ethernet cards are probably bottom-shelf knock-offs.
The problem with premade-lenght cables is you're going to run into tangles if many changes are made, and are going to end up coiling. Make that coil too tight and you're going to cause crosstalk. A custom job with all cables neatly following defined routes with no coils, twists or kinks is going to make life easier in the long term.
Re:How much is your time worth (Score:4, Informative)
Here's a link [citap.com] to a page explaining the reasons for this.
Re:How much is your time worth (Score:5, Funny)
Re:How much is your time worth (Score:5, Funny)
Inferior piece of shit.
I only use this - http://www.amazon.com/Denon-AKDL1-Dedicated-Link-Cable/dp/B000I1X6PM [amazon.com]
Re:How much is your time worth (Score:5, Funny)
Damn, my mod points expired.
As another EE (who does all their work at about 3GHz), I must say you need to be modded to oblivion for that comment.
Please, just stop.
Re: (Score:3, Informative)
Re:How much is your time worth (Score:5, Funny)
I don't see anything 'round' about your distances of 1.8288222384784 and 3.0480370641307 metres.
Not as such... (Score:5, Insightful)
They are made at specific lengths for marketing reasons. All of the "transmission line" characteristics of Ethernet cable have been solved for every length within the specified maximum.
I have a whole data center (~32 rows of 22 racks) fully cabled with lengths ranging from 100 meters to 5 inches (crossover between 1U boxes). They are cut to custom lengths, source to destination. Where their port is on the router and where they were placed in the tray add and subtract inches here and there. They run to the patchpanels in bundles about 7 inches in diameter. We have no problems with crosstalk, reflections, intermod and what have you.
If this were coaxial Ethernet we could have a fun discussion... but those days are well behind us.
Re:How much is your time worth (Score:5, Funny)
"If you've taken physics especially emf harmonics, you'd know wanting a specific length without considering harmonics is all kinds of bad because it may result in emi emission,"
Let me guess... you work for Monster Cable, in marketing perhaps?
Re:How much is your time worth (Score:4, Funny)
See, this is exactly why I adore /. Name one other popular site where you'd get ten bites on a troll that 99% of the population doesn't even understand.
Right down to the Where is the "Ignorant" mod tag? signature. 10/10 for you, sir.
Re:How much is your time worth (Score:5, Funny)
Mod parent up!
I'm an EE (non-practicing) and he's right. This is even worse with twisted pair 'cause the EM emissions come out all twisted and curvy and can cause serious interference with other cables.
It's also important to always cut your cable in multiples of 30 cm if you're going to use Gigabyte Ethernet to make sure your wave always gets to the other side in phase - you don't want a phase mismatch to happen.
Don't forget to terminate everything - i can tell you that the actual speed of a cable where one of the sides is neither connected to anything nor properly terminated is ZERO bps.
Last but not least, always make sure that both sides of the connection send equal amounts of data so that the cable doesn't get a transmission fatigue problem due to the electrons always going in the same direction.
Here you have it, the secrets of professional cable making and usage at your fingertips: don't waste them!!!
Re:How much is your time worth (Score:5, Insightful)
Uh, what part of unshielded twisted pair don't you understand? The whole idea of the twists assuages any reasonable amount of both reception and transmission externally. Modern endpoint tranceivers are really good at signal to noise problems; you can usually make cables quite a bit longer than the IEEE specs call for with total impunity. And Cat6 isn't necessary, either, just quality Cat5/5e is fine.
The only place where fast transmission cables have problem with Ethernet is at the connectors. Crosstalk there, and ONLY THERE, can be a problem unless you do something pretty unnatural to the cable. RJ-45s simpily suck because of the parallel tines. Crimp according to directions. Takes about 30sec a side. If you're worried, shoot a TDR down the line. Fluke and others make some pretty cheapo testers, or bug a cable guy to test it for you. This is not rocket science. Don't wimp out and have someone else do it. Buy quality connectors and cable, and just do it. Get the color code, follow it, and move on.
Re: (Score:3, Informative)
Not quite sure how talking about the characteristics of UTP regarding reception of external noise relates to standing waves on CAT5 cables?
I was just pointing out to the AC above that UTP cables do have different behaviour as you change the length. If you fancy a fun experiment, get a fast enough scope, and some 100M Ethernet kit and see what happens as you change the length of the cable by small increments relative to the wavelength (100MHz = 3m).
I'm well aware of how to crimp CAT5 and how UTP works though
Re:How much is your time worth (Score:4, Informative)
You miss the point.
The domain is successful Ethernet via the TIA TSB specs using the IEEE recommendations for connectivity with the signaling method employed. Good signal, no weird phase shifts or nullings, and no discriminator problems (e.g. via NEXT).
Standing waves are inevitable in non-DC cable connectivity and are a red herring unless propagation effects signal discrimination, or unwittingly becomes an antenna for other problems. In my experience (50K+ end point terminations), it's not been a problem. With a few discrete components, I can make any Ethernet cable into a wicked antenna. But the question would be: why would I do that? Standing or sitting waves (pun intended) may change ground-level, but that's when STP or 'screened' cabling is an alternative. If you need shielding because of ground-based level shift, use fiber. In fact, fiber is just about as easy to terminate as UTP these days.
Re:How much is your time worth (Score:5, Insightful)
>Welcome to the real world, where standing waves on transmission lines do exist, and you can choose lengths carefully based on the frequency going down it.
That may be true for RF, but the whole point of communication is that you get more than a single frequency - a frequency spectrum. So matching your cable length is no good for Ethernet.
In practice, there are hardly issues with standing waves, because the cable is unidirectional. So two reflections have to occur, and there is additional damping in the cable. So unless your impedance is way off, you should be fine. Even a 10% mismatch is perfectly harmless.
Re:How much is your time worth (Score:4, Insightful)
But ethernet is a broadband signal with a huge range of frequencies. You might optimise out one class of standing wave, only to bring in another. Also, the 100m length restriction isn't really to do with loss increasing wrt frequency; it's a restriction on the time of flight of a pulse. If you're trying to prevent collisions, then the time-of-flight cannot be too long, otherwise the response speed of the switches at either end is limited. (USB has a 5m restriction for the same reason).
Re:How much is your time worth (Score:4, Informative)
Gigabit Ethernet all but eliminates half-duplex (it's technically in the standard, but nobody implements it properly, and autonegotiation is required), so collisions are no longer a concern.
The length restriction is still in the standard, but most of the time it will still establish a link at 110 meters of Cat5, let alone Cat5e or Cat6.
Re:How much is your time worth (Score:4, Insightful)
Re:How much is your time worth (Score:4, Insightful)
And I believe this is the principle on which the submitter's boss operates.
Sure, you can save a lot of money custom fitting and testing every cable, but someone, somewhere is going to be late for lunch, or thinking about their hot date the night before, or busy socializing while they work, and forget to test... or overlook a bad test result, or depending on your karma, even intentionally sabotage a connection.
And while it's aesthetic to have custom-fitted and dressed cables, it's not necessary. In fact, having a meter or two of extra cable can save you some major headaches down the line when you need to alter the installation somehow. And if you're right on the bleeding edge of cable length such that an extra few meters is going to limit your performance, then you're either using the wrong cable, or the wrong protocol.
The bigger your installation, the more nines of reliability you need and connectors are the place where shit goes bad most often, so that's the easiest place to apply money to improve reliability. It's worth it to pay more for the better reliability that automated production, both lot tested and unit acceptance tested, will give you. If you're in a small company or a mom-and-pop-shop, then handmaking all your cables isn't a problem. But if you're in a large-staff or large-volume facility, then buy as much as you can, don't handcraft it.
Finally, when you compare the cost of the factory cable vs. professional-crafted, don't leave out the opportunity cost of the work that your professional is NOT otherwise doing while he's doing a job a robot could do. And realize that you're assuming that a supervisor is NEVER going to say "we need that professional to go do something else... I'll give the tedious job that robots can do to the chronically-stoned intern."
Re:How much is your time worth (Score:5, Funny)
No, you want to avoid those integer (or half) multiples of your wavelength to avoid setting up standing waves due to reflections in the cable. So go and trim a couple of picometers off those cables you just built and you'll be good to go.
Re: (Score:3, Informative)
Re:How much is your time worth (Score:4, Informative)
It's a hard limit for half-duplex. The CD part of the CSMA/CD Ethernet standard can't wait indefinitly. So they picked numbers that were just longer than the standard. Back in the old days, they would actually let you run fiber at half-duplex. I was working on an old 3-Com network that was set up by the lowest bidder. They had copper (full duplex) running at 200+ meters, but the fiber they had laid (before the copper, they had to retrofit the copper because the fiber didn't work) would fail because it would sense collisions when there weren't any and retransmit until it collapsed. One quick setting to "full" and they went from 10 Mbps copper to 100 Mbps fiber and things magically got better. So yes, the distances as far as signal level and quality are fuzzy, but if you run half-duplex (not that anyone does anymore), there is a hard limit just past. And no, I don't remember the number. Back then, I looked up the spec and calculated it by hand, but I don't remember it and figure someone has it on a web page you could find if you were interested.
This is not a time/money issue (Score:5, Insightful)
This is a CYA issue. Your boss does not want to explain to HIS boss, when a cable goes bad and the company is losing $large_number per hour until it is diagnosed and fixed, that he authorized one of his tech guys to use "homemade" cables.
Re:This is not a time/money issue (Score:5, Funny)
This is a CYA issue. Your boss does not want to explain to HIS boss, when a cable goes bad and the company is losing $large_number per hour until it is diagnosed and fixed, that he authorized one of his tech guys to use "homemade" cables.
I absolutely agree. You can't trust an IT professional's "homemade" cables any more than you can trust a cook's "homemade" meal. That's why you should always buy your work instead of doing it yourself. I went to Outback Steakhouse yesterday and ate the best steak I ever had, and do you know why? It was because THEIR COOKS DIDN'T MAKE IT! They did the sensible thing and took my order across the street to McDonald's, returning to me (at a marginal reseller's markup) a quality steak from a trusted manufacturer. And if the steak had been bad, the cooks had done their duty to their job security and could just say to their boss, "Hey, it came from McDonald's! And I'm a valued employee that has skills you need, like being able to run across a busy street during a dinner rush and buy something from another company! So you should definitely just blame McDonald's and let me get back to flirting with the hostess!" Bingo! The boss is happy, the customer gets mediocre service and quality at insane profit, and the cooks don't have any value to the business at all! That's exactly how every business should operate! Because if you trust your workers to do the jobs you hired them for, you're just setting yourself up for disappointment. Because since you weren't able to purchase your employees at an employee store and instead had to choose them yourself, they obviously must be as unqualified for their jobs as you know you are.
Re:This is not a time/money issue (Score:5, Insightful)
Doesn't help when the first question is, "who supplied that cable"? I don't know if you've been in a "root cause" meeting, but they DO get all Sherlock Holmes on that shit, I assure you.
Re: (Score:3, Interesting)
I second that.
Drive to Best Buy: 15 Min
Time to purchase: 10 Min
Drive back home: 15 Min
Cost of cable: $45 (ball park)
vs
Pull cable to desired length: 30 seconds
Crimp end 1: 1 min
Crimp end 2: 1 min
Cost of raw material: $5 (ball park)
So Unless you make about 40$ in 2 min i.e. 1200$ an hour, its better to crimp your own.
Re:How much is your time worth (Score:5, Insightful)
time out! How does making one cable run constitute reason for determining ROI on making cables based on cables per hour etc?
There are some of us who can whip out a standard 15ft Cat5 cable in about twice the time it takes to unwrap a commercially purchased cable. If you need custom sized cables, it's far easier and cheaper except for very small number of situations. If you have one cable run to do and the parts available, it makes no sense to go buy one. It's not like you're going to run out and get a 39 meter Cat6 cable at lunch time in the Mall.
Now, if you need 50 of them? perhaps a different story, but same story goes when you need 5000 of them. Savings get bigger with bulk. In this case, it was for a single cable. My suspicion is that his boss has never actually seen a well made cable created in front of his eyes. Remember grasshopper, all great Samurai swords were made by hand, not a machine with expensive dies.
Whatever happened to quality custom workmanship? It's almost as if people expect that it can't be done anymore? WTF?
Re:How much is your time worth (Score:4, Funny)
We all put our pants on one leg at a time... Maybe use Heat-shrink tubing for more ruggedness (if required) but that's it.
You put heatshrink tubing on your legs? Where the fuck do you work that you need to do that?
Re:How much is your time worth (Score:5, Insightful)
It depends on the situation and the reason for the cable.
Sometimes there are restrictions for routing the cable that makes a prefabricated cable unusable.
And you may sometimes run into problems with a handmade cable, but often it does work just fine. If you get problems - just remake one contact at a time. If you have a decently modern intelligent switch you can also monitor the port for data errors, and if you don't have any errors it's good enough.
As for cabling quality - all the outlets in buildings are usually contacted by the cable jocks from the installation company and they do a simple test and then moves on to the next. I doubt that the quality from a hand made cable and those outlets are much different.
Re:How much is your time worth (Score:5, Funny)
audio grade Ethernet cables
Yeah, I have those. I keep it next to my hydrogen grade garden hose, and my lava grade plumbing.
Re: (Score:3, Insightful)
It does when the provider uses a home-made cable as justification for line errors. Stranger things have happened.
Re:How much is your time worth (Score:4, Funny)
Get off my lawn.
Damned kids today.
Always buy them (Score:5, Interesting)
Re: (Score:3, Informative)
Aren't the commercial ones also hand made? I find it hard to imagine an automated way of doing it.
Commercial cables have going for them: rubber injection/overmold for more ruggedness, and they're pre-tested. Aside from that, I don't see exactly what should stop you from making decent ones yourself, assuming sufficient skill.
Re:Always buy them (Score:5, Informative)
Depending on wages and such, the commercial cables could easily have 10x the labor and still be cheaper.
Agreed. (Score:5, Informative)
Yes, you can use handmade cables that are as good as mass-produced factory cables. But that really isn't the issue.
It's just not worth the time spent to cut and crimp your own lines anymore. In my experience, it was a more common practice years ago in IT. That may have had something to do with the fact that there weren't nearly as many PC's or ethernet ports in buildings as there are today.
My advice: Find a good supplier (i.e. not one that charges $800 for a 6 ft. adamantium-coated cable) and do something else with the rest of your time.
meh, easy... (Score:5, Funny)
Re:meh, easy... (Score:5, Funny)
Hey, I just spent $100 on a 3ft gold-wired Cat6 cable, and I can tell that my bits are coming in cleaner.
Re:meh, easy... (Score:5, Funny)
Hey, I just spent $100 on a 3ft gold-wired Cat6 cable, and I can tell that my bits are coming in cleaner.
I hate to tell you, but the gold plated wire is doing nothing for you. The secret is in the directional indicator [denon.com]. That's where the magic happens.
Re:meh, easy... (Score:5, Funny)
Nah, I tested some ethernet cables I made with 4 pairs of wire coathangers and they performed just as well as the Monster Cable ethernet cord!
Re:meh, easy... (Score:5, Funny)
Re:meh, easy... (Score:5, Funny)
What a bunch of crap. My data transfers so much cleaner over my Monster gold-plated ethernet cabling [bhphotovideo.com], I can easily hear the difference. Just because you're bit-deaf doesn't mean that there isn't real benefit to the rest of us.
Moran.
I make my own all the time. (Score:3, Informative)
And I have never had any problem with them. Even on 50 servers running at full Gig. No errors.
Re:I make my own all the time. (Score:5, Funny)
Seconded. I make all my own patch ca$lw7 and3@0 datt trd!@m34ssion ha*F aslwts bben3n vereryu reliabl3233e.
Re: (Score:3, Funny)
How'd you get ethernet on a classic Newton?
Whatever saves time (Score:5, Interesting)
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.
Re: (Score:3, Insightful)
The problem with the "grab whatever if it's temporary" is that temporary solutions oftentimes become more permanent than anything. I have had many experiences where fixing a problem in the server room exposes some "temporary" fix from years ago that I never had time to make permanent (and since it worked, nobody thought twice about the problem it had fixed).
Or when developing web applications, somebody implements that "quick function" that does X, intended only for internal stuff. Another feature comes al
Hand-made is time consuming (Score:3, Interesting)
but makes perfectly fine cables from what I saw. I generally don't do it anymore unless I have a very custom length as pre-made are really inexpensive and over 10 cables I usually have to re-crimp at least one end. Does your boss have any proof that hand-made cables are inferior?
Create your own but TEST the cables... (Score:5, Informative)
I've learned the hard way when setting up a couple of clusters: You MUST use custom-made, cut to length cables to prevent a huge rats nets in the server room. Buying precut cables is a disaster. I had to rip out and completely rewire one cluster because I made that mistake.
However, you need to TEST the cables. And not just by plugging in and making sure it works, but a full ethernet validation tester.
I've been very happy with the Fluke Cable-IQ qualification tester [flukenetworks.com], which doesn't just make sure that the wiring is correct, but actually tests the cable up to gigabit speed to make sure everything is kosher.
Re:Create your own but TEST the cables... (Score:5, Informative)
This is the most sensible response so far.
The submitter neglected to mention how often this scenario is encountered though. If this happens frequently, buying a cable tester probably makes a lot of sense and will save a lot of money, time and headaches in the future.
However, if this happens very rarely, just buy the cable and be done with it.
Re:Create your own but TEST the cables... (Score:5, Informative)
And at $1,270.99, it's an absolute steal! [cdw.com]
Unless he's making hundreds/thousands of patch cables, I think the original poster is better off buying a commercially made cable.
Re:Create your own but TEST the cables... (Score:4, Interesting)
I guess you may need a special NIC, but even still, its gotta be cheaper than $1200.
Re:Create your own but TEST the cables... (Score:5, Interesting)
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.
Re:Create your own but TEST the cables... (Score:4, Informative)
Unfortunatly no... (Score:3, Interesting)
Something like the Fluke tester is a very sophisticated ANALOG device. Its measuring reflectivity and a whole host of analog properties, in order to determine that the cable meets the specification.
EG, it will tell you where there is an actual break in the cable.
Personally, I don't consider build-my-own cables saving money. Rather, it is some other reason (the necessity to be neat, an inability to pull pre-made jacks through the wall...) that is the reason to build your own.
He's right... (Score:5, Funny)
You can certainly screw it up if you do it yourself, for example you could forget the signal directional markings [denon.com] and then the signal would not know which way to go. Why do you think there are Ethernet cables at $500/1.5m? You think respectable companies are just trying to steal your money?
Bite the bullet (Score:4, Informative)
I buy cables because I would go through 5 - 10 cables a day and by the time I made them, tested them, labelled them, I could be doing 101 other things.
It's not to say that you can't do it, you can. It's just a matter that the amount of time you spend doing it just makes it a hell of a lot cheaper in the long run to buy them.
This is ESPECIALLY true when dealing with CAT7 or STP. On a 20Mb line (Probably a 100Mb link) the chances of having a problem though are pretty low provided you terminate it cleanly.
Don't cross the data streams! (Score:5, Interesting)
Pointy Haired Nitwitt (Score:5, Funny)
If the Belkin cable fails, you can blame Belkin (Score:5, Insightful)
Bad Attitude (Score:5, Insightful)
This principle of going with the provider you can sue over the one you can rely on is becoming far too prevalent.
I'm not saying that there's anything wrong with Belkin, and I think in this situation the pre-made cables are the better option.
However, in a more general sense, I'd prefer that my systems didn't go down rather than being able to point the finger when they do. If you are the front end provider of a service your customers are not going to be placated by the fact that, even though all their data is gone, you are currently seeking glorious retribution from the guy that solders the LEDs onto your motherboards (or whatever).
On top of this, when things go tits up at three o'clock in the morning - you can be sure the Belkin shop won't be open.
Re:If the Belkin cable fails, you can blame Belkin (Score:5, Insightful)
If something happens with the Belkin cable, you can blame Belkin.
That presumes:
Besides, do you really want to crimp your own cables?
Yeah, but I'm one of those crazy people who fix their own fences, hang their own ceiling fans, build treehouses for their kids, and generally like to do things not conducive to the strictly consumer lifestyle.
Rewiring our building (Score:5, Informative)
We had a contractor come in and rewire our facility. They ran raw CAT 6 and hand terminated it, then TDR'd each run.
Your boss is unclear on the tools needed and the difficulty...just simple hand crimpers were all they needed. There's going to be
an impedance bump at the RJ anyway...the cable's not twisted there.
As to making them yourself or buying patch cables? It's way cheaper to buy them (I like L-Com) but if you need one *right now*,
(or a custom length) it's cheap to have a crimp tool, some RJs and a roll of cable handy in the corner of the office.
Doubt he's correct, but believe him anyway! (Score:5, Insightful)
Wait a minute. Your boss is telling you to buy cables instead of toiling to make your own, and you're _complaining_? I don't think a self-terminated link of CAT6 will have the slightest trouble maintaining 20 megabits, but that's not the point.
Word of advice, take his word for him and nod. If he's willing to spend money to make your job easier, then keep that job!
Not worth the responsibility (Score:5, Insightful)
Your boss is a dumbass.. (Score:5, Interesting)
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 only use monster ethernet cables (Score:3, Funny)
It really preserves the assonitic complexity and quality of the packets when they move from your wall to your router. Cheaper cables let noisy bits through that go all wobbly and clog your connection. I hear their new wifi cables are hella expensive but totally worth it.
How do you want to spend your time? (Score:3, Informative)
I've bought thousands of dollars of cable. Full disclosure, it has been BNC cable, and not ethernet, but I think my experience is likely germane. This cable has been used to construct installations of scientific equipment that gets reconfigured pretty frequently (and I've been the primary user on most of this equipment). I have never, ever had a single cable-related failure using ITT/Pomona cables. My peers, on the other hand, use hand-made cables and are constantly debugging their setups.
I spend my time doing my job (collecting data), while other people in my lab spend their time fixing problems. (Really full disclosure, I'm the only one with an EE degree.)
Good cables can be found inexpensively. These are the ones you want. Cheap cables can be found for less money, but these are the ones you do not want. Custom cables, unless you have high-quality crimping tools (the $39.99 variety don't cut it) and a proper means for doing testing, which means TDR and bandwidth testing in your case, just are not worth it for general-purpose use.
Look at it this way: how long does it take you to generate a qualified cable? Not how long does it take you to make one cable, but how long does it take you to make one cable that you will use, including all of the failed crimps, cables that were cut too short, too long, were miswired, or must be discarded, for some other reason. How many cables will you be making? Total that up and use 1/2 of the time to search for low prices on high-quality cable instead. You will be ahead in the end.
At NASA I regularaly good cables, (Score:3, Interesting)
with equipment that's not much different than stock equipment. I test these cables with a DTX-1800, they do great.
They're sticklers for BlackBox brand cable, I don't know if it's because the cables good, or the more likely scenario that instead of specifying TIA-568B compliant cable they have have to give a part number to make a "Typical". A "Typical" is a blue print for a cable. Remember, it's government, loads of red tape.
We also use Black Box brand connectors, again, for part number reasons I'm almost certain. For the Cat-5 stuff there is something a bit different than your run of the mill cables, it's the inclusion of black load bars that get crimped into the connection. A bit different than most connectors I've used.
The only Cat-6 I've made was a specialized connector with additional grounding added, so I wont get into that.
Beyond what's mentioned the only difference between NASA and the rest of the world is the use of really expensive test equipment, and the insistence that calibrated ratcheting crimpers are used. For test reasons I've made cables using my own stuff and put it on the Fluke, I hate to say it, but my uncalibrated out of the box $20 crimpers from Ideal do just as well as there $150 at minimum crimpers that are custom pieced together. At least according to the Fluke.
Field Crimping Cat6? (Score:3, Insightful)
Be Careful! (Score:3, Informative)
Solid core has slightly better propagation properties (the 100M limit implies solid core for example) however it also acts similar to a wire coat-hanger. Like any metal it weakens as it bends and after a period of time it'll grow weak, thin and even completely break.
Stranded is similar to a braided rope, it can withstand constant reconnections (user area, especially common with laptops), movements (telcom closets when you're moving the cable mess to access equipment ports) and the stress that will wear down the solid-core cables.
Do yourself a favor and make sure that if you create your own patch cables:
There's nothing wrong with making your own patch cables, and it could potentially save you big bucks (compared with buying a $35 patch cable at a local store). However if it's not done right you will kick yourself down the road -- or more likely blame the network electronics, server, network cards, or whatever you normally blame. :)
Drill test (Score:5, Insightful)
Best advice I've ever heard on cabling:
If you have to drill holes to run it, make your own. If you don't buy it premade.
Second best advice:
Test it all. Even if it comes in a shrink wrap package.
Funny (Score:3, Informative)
That's funny.
I mean, a couple of weeks ago I finished up a job where I went into a mess, with a mix of premade cables and mixing A and B pinouts. I re-did most of the connections - by hand - and installed all new patch cables - made by hand, and tested every link with a TDR. A couple failed - turned out the oh-so-slight crosstalk between T568B patch cables and the old T568R runs was just enough to break the link so I switched those old connections to T568B and all was well.
I've seen articles which claim the crosstalk from mixing A and B only sometimes cause link problems, but I've seen it often enough to make it a blanket rule to always, always, always go 568B. 568B is supposedly deprecated but every cable I've ever bought off the shelf, aside from crossover cable, has been wired 568B so I always stick with B.
Most of the premade patch cables that were on site tested bad BTW. I've since installed a few premade cables but they were brand new and those tested fine.
If you're going room to room, don't go with premade patch cables. Get a spool of CAT-6 and use keystones (jacks) on the PC side and a patch panel (or keystones if the boss is too cheap - although once you do more than 20 jacks the patch panel becomes much cheaper so just tell him to STFU and do it right, and skip one appetizer and alcoholic beverage at a meal to recoup the cost) on the other side. Just hanging a patch cable out of the wall is really hack. It works, but it's fugly.
Re:your boss sucks at making ethernet cables (Score:5, Insightful)
Obviously your boss isn't good at making cables. While if you lack the skill to do something like make cables with care you're going to have problems, there's no reason that you can't make your own cables and have them perform just as well as the ones made by a machine in a factory.
They can put it under the "Tech" section if they like, but this is really another disappointing Ask Slashdot. It's disappointing because too many of these have this format: "my boss at work wants me to do X, but I'd really rather do Y; what are the merits of X versus Y?" All of them need to be summarily rejected, with a polite e-mail sent to the submitter which says "within the bounds of the law, you need to do what your boss asks you to do whether or not you necessarily agree with it. If you cannot convince your boss to do otherwise, and this is a problem for you, perhaps you should consider working elsewhere."
The other disappointing category of Ask Slashdot-type submissions are those questions that are factual in nature and have only one correct (and rather well-known, easily researched) answer. Asking a large group with varying levels of expertise makes a lot of sense when there are multiple possible solutions to a problem and there is room to be creative. It makes no sense when it's more of a yes/no question -- remember the recent Ask Slashdot that asked whether spam is increased by trying to opt-out of spam e-mails? That's an excellent case in point, and not atypical either. That should have been an "Ask Google", not an "Ask Slashdot".
I think it's a shame that the quality of these particular submissions are on the decline. There's nothing inherently wrong with the "Ask Slashdot" format and there are a lot of very knowledgable people who browse this site. I'd love to see how creative they can be. It's just never going to be as good as it easily could be when it's handled this way.
Just pretend that the question is... (Score:3, Insightful)
It's disappointing because too many of these have this format: "my boss at work wants me to do X, but I'd really rather do Y; what are the merits of X versus Y?" All of them need to be summarily rejected, with a polite e-mail sent to the submitter which says "within the bounds of the law, you need to do what your boss asks you to do whether or not you necessarily agree with it. If you cannot convince your boss to do otherwise, and this is a problem for you, perhaps you should consider working elsewhere."
Just pretend that the question is "how should I convince my boss that Y is better than X?". It's like asking legal questions on Ask Slashdot: the real question is "what should I know before my appointment with a lawyer?".
Re:your boss sucks at making ethernet cables (Score:5, Insightful)
Bull! Entirely aside from what the submitter should do to protect their job, it is topical on slashdot to question whether DIY ethernet cables are any good, just as people on a home repair DIY site might discuss whether doing drywall yourself is worthwhile.
When the only answer slashdotters can imagine is "just pay somebody else to do it," that is the day there is no point reading here.
Re:your boss sucks at making ethernet cables (Score:5, Funny)
When the only answer slashdotters can imagine is "just pay somebody else to do it," that is the day there is no point reading here.
Hey, that was pretty good. What would you charge to make my posts for me?
Re:your boss sucks at making ethernet cables (Score:5, Insightful)
They can put it under the "Tech" section if they like, but this is really another disappointing Ask Slashdot. It's disappointing because too many of these have this format: "my boss at work wants me to do X, but I'd really rather do Y; what are the merits of X versus Y?" All of them need to be summarily rejected, with a polite e-mail sent to the submitter which says "within the bounds of the law, you need to do what your boss asks you to do whether or not you necessarily agree with it. If you cannot convince your boss to do otherwise, and this is a problem for you, perhaps you should consider working elsewhere."
I don't know about you, but I was hired for my technical expertise. It is part of my job description to let management know when they are making bad technical decisions. If they still insist after that, then sure, I gotta shrug my shoulders and do it; but until then, it's my job to find out the facts and make sure they stay informed...which is exactly what the questioner is doing.
Save the "shut up and do as you're told" bit for McDonald's burger-flippers. We're professionals here.
Re:your boss sucks at making ethernet cables (Score:5, Insightful)
Here's how people screw up cables:
1. They just match colors at either end and don't pick a standard pinout (T568A or B). That might result in a usable 10mbps link, but it won't work at 100 or 1000.
2. They mix 568A and 568B - usually wiring A in the wall, and using premade B patch cables. Instant crosstalk. OK on very short runs, but anything longer than 80' to 100' will become problematic with many NICs.
3. They score the insulation. Use the right tools, and adjust the tension on the stripper.
4. They only strip 1/2" of insulation and try to organize the cables and jam it in, so you don't get a clean connection on all the conductors - or might miss one completely. Strip the insulation back 2", then you have room to sort the conductors, trim them neatly then you can slide them all the way to the end of the terminator, then the clips will "bite" each conductor twice - cleanly, resulting in a good connection and a strong link.
Your boss sounds like an idiot and a hack.
If you're going from the wall to the PC I'd say yeah, buy a premade cable and save on labor. Just buy a good one. Believe it or not monoprice's cheap stuff is extremely good.
From the patch panel to the switch, it depends on the length. Will a premade cable fit the length well? Go premade. If not, then make the cables.
Ultimately though, your boss is the boss. If he insists on hanging patch cables loose through the wall, etc. just document it in email, send it to him with your recommendation, etc. so that when he comes back to you complaining that it looks hack or that the cabling was overpriced, you can remind him that you recommended otherwise.
Re: (Score:3, Interesting)
If you get the rated speed and it's reliable, need we delve further?
But how can you be sure that a cable is as reliable as you think it is without a $1,200 device [slashdot.org] that comprehensively tests the reliability?
Re: (Score:3, Insightful)
And why not? The only reason I ever bothered to learn how to make patch cables was because I had bosses who didn't want to spend the extra money to buy commercially produced stuff. If your boss is giving you the OK for the money, then place an order online and have a whole bunch delivered straight to your door. Nothing could be easier.
I can produce cables all day long and something like 99% of them will be easily good enough for my needs. Still, I wouldn't doubt that a company like Belkin, running an e
Re:Just do what your boss wants (Score:5, Insightful)
It's clearly not your company's core business to make their own patch cables. It may be fun for you to wittle down your own toothpics from lincoln logs but if it's not in your job description it ain't going to fly. Seriously, just buy the damn stuff and do what your boss has asked.
Exactly.
We buy all our patch cables in bulk. There's no reason for me to assemble a new cable every time we want to patch in another machine. It may not take long to throw together a 6' cable, but why waste any time at all? Break open a package and plug it in. Done.
We do keep a couple spools on hand, and some wiring tools. If we absolutely need a 15' cable and we don't have any on hand we'll throw one together...
Or if we really need a new wall jack somewhere... It's good to have the capability to do some of your own wiring if necessary... But for anything substantial we'll contract someone else to do that, too.
But, really, that isn't what I'm paid to do.
Re: (Score:3, Informative)
I've used both handmade and commercial cables and there is big difference in the connectors. When I crimp it myself (or get cheap pre-made ones) the only thing holding the connector on is the little metal spikes inside it. With decent commercial cables, there is moulded plastic connecting the ends on to the cable, which is a lot stronger.
Whether it's worth going for the expensive option depends on whether the cable will be plugged in and unplugged a lot or whether the ends are likely to have sharp bend