OT: Re: [lug] cat 5 cable

Nate Duehr nate at natetech.com
Wed Dec 5 01:53:17 MST 2001


All of these questions should be covered in any good basic cabling book
for data cabling these days.  There are specs for the maximum distances
on Ethernet for Cat 5 for both 10 and 100 Mb/s networks.  Exceeding the
Ethernet spec distances on good quality Cat 5 or Cat 5+ cabling can be
done, but expect lower performance and strange problems with your
network.

Solid core is all you're going to find in true Cat 5 rated cabling. 
Stranded is typically Cat 3 and used only for voice.  Stranded cables
are also a complete pain... I'd avoid them.

The standard lengths for Ethernet networks are typically listed in specs
is for Cat 5.  Cat 5+ stuff is really not necessary in most situations. 
However many folks are recommending Cat 5+ or sometimes called Cat 5E
cabling to start out with if you're planning for higher speed networks
later.  (Pulling out a wiring closet to up speeds is no fun -- been
there, done that too...)

If you're putting the ends on the cable yourself, do yourself a favor
and purchase a GOOD quality connector (Amp comes to mind here) and good
quality crimp tools.  Those sideways things that most Home Depot's sell
royally suck for doing hundreds of cables -- and you'll have a
horrendous failure rate unless you're REALLY slow and precise with
them.  Most of the time you're trying to get the job done and over with
though, and the right connectors and crimper will make your whole day a
lot better at relatively little cost.

[By the way, many people do not realize that there are DIFFERENT RJ45's
for solid core and stranded core wire.  Many manufacturers have gone to
a "hybrid" type that will work on both, but if you're buying quality
stuff like Amp, you'll see they have two different part numbers for a
box of 100 RJ-45 connectors -- one for solid core wire, one for
stranded.  Put a solid core connector on a stranded wire or vice-versa
and you're bound to have lovely problems later when they all work their
way loose.  I spent a week cleaning up a site that did this by accident
on over 200 cables -- both ends.  Heh.]

There are an awful lot of good cabling companies out there that do good
work and almost as cheaply as you can do it.  If you have a LOT of
cabling to do, you may want to consider letting them speed up the
process for you by doing it all over a couple of weekends, or whatever. 
They'll typically do all punchdowns (if needed in your cabling plant),
labeling, testing, and provide you with a printed report showing all
pairs functional, as well as doing a nice job tie-wrapping bundles of
cable and following fire codes as necessary.  -- For example, if you
have to go through a firewall, you have to reseal it with fire-retardant
sealant, etc... if you're doing things "right".  Of course, many many
places DON'T.

By the way, make sure you know whether or not you need plenum-rated
cable as well.  Fire codes typically require plenum rated cable in
overhead drop ceilings and other unexposed places in office
installations and not using it can result in big fines or the fire
marshal shutting down your building during an inspection and kicking
everyone out.  (Not likely, but they COULD.)

Here's a web site that talks about ALL this stuff... I just found it
with a Google search, there are hundreds more like it but this one
looked pretty accurate.  It talks about EIA/TIA 568A vs. 568B wiring
standards and almost all the stuff you'll need to know about cabling
Ethernet networks over Cat 5...

http://www.atcomservices.com/highlights/cat5notes.htm

Nate Duehr, nate at natetech.com



On Tue, 2001-12-04 at 13:37, Hugh Brown wrote:
> > I can suggest you need the "Fast" cat 5, else you lose 100 Mbps real
> > quick over distances. It's a bit more expensive than plain cat 5. Even
> > CompUSA sells this, last time I looked the regular cat 5 was on the
> > left, and fast cat 5 on the right, higher price for same basic length. I
> > don't know if their prices are reasonable or not, but they do have some
> > fairly long lengths available if you're in a hurry. I do not know about
> > best or worst for particular connectors, maybe try J.B. Saunders over on
> > Foothills highway off of Valmont (it is possible they can tell you what
> > makes the good hand-made cables).
> 
> I'd love to, but that trip would cost more than the cables. :)  I think
> I want stranded instead of solid after looking at a few websites.  I
> will look at the Fast cable.  Thanks for the input.
> 
> Hugh
> 
> _______________________________________________
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