[Le Flaneur]

We want to install a wired ethernet network in our new home. I have a friend who is an experienced network installer, and he says that 100 MB/s is all I need, but it seems silly to me to limit oneself to that bandwidth these days when Gigabit will eventually become very widespread. Specifically, I'm interested in Gigabit as a LAN speed, for the following reasons:

1. iPhoto sharing (which seems slow even at 100 MB/s)
2. LAN backup to a Gigabit network attached storage device, such as the Linkstation

Will Cat5e suffice for Gigabit ethernet, or do I need Cat6? My friend says that he has some sort of device that will measure the speed of the network, but it doesn't read Gigabit speeds. Is that a problem? What does "termination" mean in terms of a wired ethernet, and are there special installations considerations for Gigabit Ethernet? I'm thinking of a very simply network -- only about 2 rooms.

[tooki]

Cat 5 (not 5e!) is all that is required for Gigabit by the standard.

It shouldn't be a problem to run Gigabit-capable cable. If your friend's tester is showing problems, either a) there's a source of interference, such as cable running across a fluorescent tube ballast, or b) indeed the cables aren't terminated correctly. The Cat 5 standard requires that no more than 1/2 inch of the wires run untwisted (e.g. in the plug, or at a patch panel or wall jack). It's certainly possible that if a flaw exists in the termination, Gigabit would be more sensitive to it than 100Base-Tx.

tooki

[Le Flaneur]

Originally Posted by tooki

Cat 5 (not 5e!) is all that is required for Gigabit by the standard.

It shouldn't be a problem to run Gigabit-capable cable. If your friend's tester is showing problems, either a) there's a source of interference, such as cable running across a fluorescent tube ballast, or b) indeed the cables aren't terminated correctly. The Cat 5 standard requires that no more than 1/2 inch of the wires run untwisted (e.g. in the plug, or at a patch panel or wall jack). It's certainly possible that if a flaw exists in the termination, Gigabit would be more sensitive to it than 100Base-Tx.

Isn't Cat 5 the *bare minimum* for Gigabit? So termination is literally the connection between the cable and the wall jack?

[indigoimac]

I'd go for CAT5e, it's likely cheaper anyway

[ghporter]

Cat 5 is pretty much all you need for gigabit speeds, though you may notice better noise isolation with Cat 5e-but only if you're equipped to measure it.

From what I've seen around here, Cat 5e can be a "premium-priced-product." It's running 79¢ for name brand (Belden) plenum-jacketed cable, and 36¢ per foot for non-brand plenum cable. Cat5, on the other hand, is going for 17¢ per foot for Belden non-plenum cable. I always recommend plenum-jacketed cable because you never know where you're going to put the cable when you buy a spool.

[Le Flaneur]

Originally Posted by ghporter

From what I've seen around here, Cat 5e can be a "premium-priced-product." It's running 79¢ for name brand (Belden) plenum-jacketed cable, and 36¢ per foot for non-brand plenum cable. Cat5, on the other hand, is going for 17¢ per foot for Belden non-plenum cable. I always recommend plenum-jacketed cable because you never know where you're going to put the cable when you buy a spool.

What is "plenum-jacketed" cable? Are all RJ-45 jacks created alike?

[ghporter]

Jacks are pretty much jacks (unless they actually look like crap). "Plenum" cable is rated for installation in airflow spaces because it won't give off toxic vapors in a fire. PVC most certainly DOES produce toxic vapors in a fire, so it's a violation of code (and law in most places) to install non-plenum cable in spaces that are used for ventilation.

[Le Flaneur]

Originally Posted by ghporter

Jacks are pretty much jacks (unless they actually look like crap). "Plenum" cable is rated for installation in airflow spaces because it won't give off toxic vapors in a fire. PVC most certainly DOES produce toxic vapors in a fire, so it's a violation of code (and law in most places) to install non-plenum cable in spaces that are used for ventilation.

So if I run bulk cable through walls, I should use plenum cable?

[indigoimac]

what do you mean by though walls, one thing i heard was, if it goes between floors you need plenum, if it's only on floor you don't.

[Le Flaneur]

Originally Posted by ghporter

Cat 5 is pretty much all you need for gigabit speeds, though you may notice better noise isolation with Cat 5e-but only if you're equipped to measure it.

Are you really an expert on this? Because this isn't what I've heard. For example, Andy Inhatko wrote me this:

Cat5: The cable you're holding will probably work at gigabit speed.
Cat5e: Will _definitely_ work at gigabit speed.
Cat6: Will definitely work, and if you have any network problems, you can _probably_ assume it's not the cables.

So since I don't need that much cable, and Cat 6 isn't that expensive as a patch cable, wouldn't it work to buy Cat 6 patch cables in 100 foot lengths and simply cut off the connectors at both ends?

[ghporter]

You're talking about a lot of work and extra expense in cutting up 100' Cat 6 patch cables to use in a fixed installation. You'll be throwing away a bunch of RJ-45s (which cannot be reused), and you'll probably also wind up using far more cable than you need because of the way things wind up measuring out. It's always better to pull infrastructure cable from a spool because you KNOW you'll have plenty until you get down to the bitter end of the spool. You can get partial spools and "boxes" at lengths of 500' or so, so you don't need to buy 1k' and only use half of it.

indigoimac, if a space is supposed to be used for airflow, it counts as a plenum, so plenum cable is mandatory. To be on the safe side, use plenum cable everywhere.

[Le Flaneur]

Originally Posted by ghporter

You're talking about a lot of work and extra expense in cutting up 100' Cat 6 patch cables to use in a fixed installation. You'll be throwing away a bunch of RJ-45s (which cannot be reused), and you'll probably also wind up using far more cable than you need because of the way things wind up measuring out. It's always better to pull infrastructure cable from a spool because you KNOW you'll have plenty until you get down to the bitter end of the spool. You can get partial spools and "boxes" at lengths of 500' or so, so you don't need to buy 1k' and only use half of it.

We're talking about wiring two adjoining rooms on the same floor, so that's *way* less than 500'. 500' of *PVC* Cat 6 is at least $80, and so more of that would be wasted than with two or three patch cables.

My friend says that plenum is only for air spaces and would be overkill to link two rooms on the same floor via attic. True/false? The cable specs say, "CM/CMG rated for single floor, general purpose use in walls and ceilings.

[ghporter]

Ohhhhhh. That's different. I had the impression you were wiring a whole house. In that case, your plan to buy 100' Cat 6 cables and cut them to fit your needs would indeed work much better.

Your friend is correct that plenum cable is required only for air spaces, but on the other hand, you're working in a residential space where just about everything could be involved in a fire. I still say be safe and spend the extra for plenum cable. By the way, most patch cables that I've seen are made with plenum cable anyway.

[tooki]

Not the ones in retail. They're almost entirely PVC.

Plenum cable is usually not as robust against wear and tear, which is why it's not usually used for patch cables. The other thing is that plenum cable is usually solid, whereas patch cords are stranded for flexibility.

tooki

[ghporter]

I must have seen "locally manufactured" patch cables then... They used anti-snag boots and everything, so I figured they were factory made. And I'll keep an eye on what I use, too.

[BLAZE_MkIV]

Home depot and such usually sell cable by the foot.

[Cadaver]

As for speed, I can tell you that gigabit ethernet may make a speed difference.

I have a G4 file server networked to a couple computers here at home via gigabit ethernet, and I've seen file transfer peaks well above 250 mbit/sec. Obviously faster than speeds that you can get at 100 mbit ethernet.

The file server is in the basement, about 50' worth of cable away. I used a $30 Cat 6 cable purchased at CompUSA. The file server and three other machines (a MacBook Pro, a G5 and an AthlonXP-based PC) are connected to a D-Link 5-port gigabit switch. The client computers are connected via Cat 5e cables (about 14 feet each).

[Jercro]

Most of the standard network adapters, routers, switches, etc. are only good to 100/bT I think. You would have to buy a special router to connect Gigabite. Redundant if you are connecting direct of course, but we would assume you are connecting through a cable or dsl modem to the internet so a router would be the preferrable way to go. If you are direct connecting the computers it shouldn't make any difference. Use the best wire available at your local electronics supply or hardware store. Make sure you reverse the connections for the direct connection. You cannot connect direct with a standard Cat5/5e ethernet cable. You need to use what is called a jump cable which has some of the wires reversed in the connection on one end.

[ghporter]

There are valid and practical uses for a gigabit LAN no matter whether you have a broadband connection or not. Transferring large files is a major one-who wants to wait for a long time to transfer files? So getting a gigabit router and feeding it with a broadband connection that tops out below say 10Mbps isn't a waste of time.

You still need gigabit capable cards in all the computers you want to transfer those files between, though, but the price of gigabit network cards is coming down as more manufacturers get into making chips for them.