I need help building a LAN...

[Malpine Walis]

I built my home LAN by surface mounting the wires right on my walls. Now that my employer knows that I can do this, I have been called on to network the building.

What I have to work with is a relatively large are above the ceiling. But I need to share this area with all of the building services (HVAC, electrical, phone lines, lighting etc). I hear that the electrical interference from all of these systems can cause problems with network transmission.

I need to see any resources that anyone knows about that would allow me to determine what I need to avoid when I start running the cables.

[Shep]

use cat5 and if you can prevent it don't run it in parallel with any electrical wires, that should help with interferance.

[Jon]

It's also necessary (by law) that you use plenim grade cable when running through ceiling/floor spaces. Most bulk cable is plenim grade so it shouldn't be hard to get.

[Malpine Walis]

This much I know. I already have 10btx cards in all the computers and plenum cable is part of local fire code.

What I am most concerned about is RF interference from the stuff in the celing.

How do I figure out what is relevant to my situation and how far do I need to be from each source to get the best possible transmission speed?

[Jon]

In my experience at least a foot from phone/electric cables and any electric motors (fans) that may be housed in the area you're working with. Any extra room you can add, the better.

[chaim79]

The biggest note is to stay away from florescent lights, they will kill transmition fast.

How big of a job is this? how many workstations, servers, etc?

E of E

[Crash893]

get a AM radio pull the antenna all the way down
anywhere you get a lot of static is places you sould avoid

if your just running at 10baset then it shouldnt matter that much

also there is such thing as shielded cat-v
its basicly got tinfoil wraped around the inside.
but of course it costs more.

there is also some stuff you can do with a fiberoptic ( i know a place that sells it relativly cheap.)

[Phugbox]

Well, i feel I might have some input to this, should be nice to hopefully provide good info on a first post.

Having gotten my certification for Session One of the Cisco Systems Networking Certification Course (big words, and pretty empty too, bu I like them) but hey I learned some things.
First off, as mentioned before by others, running cables past Flourescent lights is a prime example of what you don't want to do. As for electrical devices, an device with electric current, or a motor, or anything of the like will generate interference. Keeping paths past these to a minimum would allways be nice, but oh well. Just avoid High voltage lines. running them past incandescent lights is fine, don't worry about them. As for the rest, shielded cable is nice, fibre-optics are great for avoiding intereference, and good for speed, but not technically needed unless running network cables across "open ground" between buildings, Never, Ever use cat 5 cable for that, they have a nasty tendency of getting hit by lighting and possibly killing anyone sitting at they're computer. I shouldn't have to say this, but that would be considered BAD, real Bad.

but yeah, avoid flourescents, and keep all cables lengths to under 1000 feet in total length from server to workstation, workstation cables included in length calculations.

I'd mention what my computer is but it's embarassing, wait until end of Jan though, then I won't feel so bad.



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[Crash893]

not true fiberoptic can be run from router to routher in the same room ( cisco 12016's with 10 trident cards)

single mode fiber optic is used for long distances

also they make cat-v surge protectors belive it or not.

i was thinking if you got some sort of ducting that would elminate most of the em interferance ( just get some metal poll or something attach it where the cat-v will be near the light and run it threw there.

[chaim79]

oddly enough if you run cat5 through that foam insulation that is put around water pipes (the kind with the hole in the center for the pipe and a cut to fit it around the pipe) it will actually shield it from some of the EM... don't ask my how or why.

One of my friends who worked for a place that put in cat5 for a business had no choice but to run a line over a florecent light, they tried everything and finaly hit on this solution... they had no clue as to why it worked but it did.

I'm not sure if it needs to be a spacific brand or something, he couldn't remember what it was.