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Category 6 UTP Standard is (finally) Here
An anonymous reader writes "This is only important for the networkphiles out there, but the Category 6 UTP specification is finally here. The standard is the TIA/EIA-568-B.2-1. The significance of this is that now you can transmit at 250Mhz frequencies (vs 100Mhz of Cat 5/5e). So 1Gbps is easily achievable. Of course ther's still Category 7 (600Mhz) in development, but I guess we should eventually move to fiber." Who
hasn't crimped cat-5 before?
...When you're wiring about 500 workstations and servers over a reasonably sized office. You run into having to buy literally *miles* of cable when you wire even a medium-sized IT office. At that volume, buying Cat6 or Cat5 is non-trivially less expensive than fiber.
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It wasn't cat-7. It was level-7 as proposed in Anixter's Levels Program. I believe it was 500MHz cable but the standard isn't finalized yet.
Although, I suppose it should be theoretically possible to create a standard that uses just one universal ground wire for a 600x7 = 4.2Gbps rate...
Uh, last I checked, Ethernet is a balanced signal, there is no ground. This eliminates problems with ground potentials between two distantly seperated devices.
It's basically like this
Pair:
TX+
TX-
Pair:
RX+
RX-
High signal might be +5 and -5 on the other, in relation to some certain ground. There is no single point of reference per se, it's just the difference between the voltages. The same signal may appear to be +7 and -3 at the other side, but it doesn't matter that the ground potential is different, since the difference is the same.
I think GB ethernet does something slightly more complex, but I believe that is a balanced system too. Coax is unbalanced, there is a ground on the sheath, hence you use a Bal-Un (Balun) (balanced to unbalanced) to convert between the two.
Also your post is ignorant in other ways, you think we can only encode one bit per cycle? This is analog we are talking about here, things like QAM let you get several bits per cycle.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
CompUSA is already advertising the cable in their circular for $25 in 7 feet quantities.
Of course, it's probably going to be cheaper to crimp it yourself, but at over $3 per foot, it's quite expensive.
-- If you try to fail and succeed, which have you done? - Uli's moose
Yes, it will increase the distance that gigabit copper can be run, as well as increase the signal-to-noise ratio. With gigabit switches starting to hit the market at decent prices now, I'd be very surprised if we saw slower hardware than that making use of Cat6.
Is your browser retarded?
Cat5e was specified for 1gpbs over copper.
Same with Konqueror. this seems to be done in JavaScript
So turning off Javascript fixes it, but it is still annoying
Cat5 uses only four of the eight wires for data. Two of them are for sending and two are for receiving. Thus, 100 Mhz = 100 Mbps.
CAT6 uses all eight wires. They also multiplex between sending and receiving. Adding the extra set of wires doubles the bandwidth, and multiplexing doubles again. Thus 250 Mhz * 4 = 1 Gbps.
>Higher frequency signals/noises travel easier and farther.
No the opposite actually. The paralell capacitance and the serial impedace together for a low pass filter. So it's harder to send a high frequency signal down a wire.(this is why thay must improve the cable to do so) The bandwidth(efectivly the highest frequency that can be sent) however is nessesery for sending at a high bitrate. Imagine sending 101010101010101010 down the line. That whould basically create a square wave. The fundamental(the lowest frequency in a signal) whould be half the bitrate, the first(3rd. actually) harmonic whould be 3 times the fundamental and 1.5 times the bitrate with one third the voltage of the fundamental (such is the tao of the square wave) and so on. But not all of the harmonics are needed to get the data across. So in the end you get approx. the bitrate of the bandwidth(often bw. is used to mean bitrate) but it depends on the encoding method. This is why cables that can handle higher frequencies are needed.
FRA: STFU GTFO
You make patch cables out of the same cable that you run through your house? While you might have gotten lots of experience crimping cables in doing your house, you obviously didn't do very much research. If you are going to lay semi-permanent cable through your house, you should be using solid-cored cable. First of all, it is less expensive than stranded cable, which is important since you're using it for long lengths. Secondly, the keystone jacks and punch-down blocks are designed to cut through the insulation into SOLID cable. On the other hand, the knives in the crimps for patch cable are designed to cut down into STRANDED cable. If you try to use one type of cable for the other's purpose, you can end up with poor connections at the crimps and the punch-down blocks.
When I wire offices, I always make sure I have a spool of each type of wire.