View Full Version : Fibre-Optic vs. CAT5

21-03-2003, 05:04 PM
I'm just wondering, in these two situations, what would operate faster?

1. Computers networked using CAT5, then from the switch to the server 30m away using Fibre Optic

2. Computers networked using CAT5, then from the switch to the server 30m away using CAT5

I'm just thinking that in theory, the speed of the network is limited by the switch, and no matter if you use CAT5 or Fibre Optic, it will still go at the speed which the data is coming to/from the switch. Does anybody know a definite answer?

Graham L
21-03-2003, 05:10 PM
If you run the fibre at 100 MHz, it will be the same speed as Cat5, though there will be a slight extra latency due to the conversion to/from optical.

If the fibre is at 1000 MHz, it will be faster than wire. It will also be be a lot more expensive. :D

21-03-2003, 05:14 PM
Ok. Thanks Graham.

The reason I asked this was because at school a computer room is linked to the server using Fibre Optic. However, late last year the cable appeared to have been damaged somewhere between the computer room and the server room. It has been replaced with a tempoary CAT5, however it is still slower than it used to be.

21-03-2003, 05:41 PM

cat5 will pick up crap from power cables Ect and fiber will not this give a speed diffrance.

21-03-2003, 05:53 PM
Well if they're both laid out correctly and meeting specifications. There would be a difference.

But I don't think that the difference will be usually noticable, depending on what the network is used for ofcourse.

Graham L
21-03-2003, 05:55 PM
"Observed" network speed is meaningless. It has to be measured.

Noise can slow down links because repeats are needed. It is a problem if it can be measured ... and it can be measured. The repeats are logged.

22-03-2003, 04:21 PM
Why don't you go for CAT6 cabling? Apparently they're much better quality than the CAT5e...? And only about 5$ more expensive for the same length on average from DSE.

Graham L
22-03-2003, 04:33 PM
There's a very good reason. 100BaseT using Cat5 cable runs at 100 MHz. Using Cat6 cable it runs at 100 MHz. :D