using telepphone cable for ehternet cable

Dear all


now i have a 50 pair telephone cable , can i take 4 pairs ( or just 2 pair ) and using it for making an Ethernet cable


thanks

bye

Hallo,
What is your distance & net bandwidth pls?.

For shorter distances as 100 meter(s) it must be possible, but depends on your net bandwidth & type of cable (as capacitance on your source)...
K.

Standard telephone cables are almost meeting the CAT III specification. So you can refer to respective ethernet max. length specifications and empirical experience.

Dear FvM,
Im sorry, but standard is relative! What for us is alldays thema; for other only a dream(maybe)...
In much countries you can find only "(very)old style" cables_ this 50 pair telephone cable indicate for me the same, its is maybe not an plastic isolated...
The old cables are to use practically in paar hundred KHz band only.
Even, as you wrote: it is to try some experimentation!
K.

The old cables are to use practically in paar hundred KHz band only.

Click to expand...

Sounds unlikely to me, but I must confess, I never measured an "old" tissue isolated, lead jacketed cable. I would expect
however a characteristic impedance similar to recent cables. High frequency loss may be slightly different, of course.

I worked good 30 years ago wid PTT cables, the highbandwith ones are possible to "tune" for 108 KHz multicarrier systems end their damping...
It has had amps in all 8/12 km distances, bandwidth dependend.
K.

Yes, I see. But I think it's the same with today's cables. They can carry high frequency DSL signals with huge attenuation
and a complex equalizer over a few km at maximum. 10BASE-T means 5 MHz signal bandwidth over 100m only, with
moderate attenuation. 100 MBit works over some 10 m according to my experience.

well

it is 50 pair jelly filled telephone cable , very new cable and not old , for 100Mbps ethernet Lan , so what for 50 meter and for 100 meter and for 300 meter

thanks all
bye

Then apply it pls, dont worry/hesitate_be active!
For your such 100 meters it should function...
In all cases my question states: what is your net bandwith?
K.

it should work for 10 base T
it should work for 100 base T if you use a hub
it should not work with a 100 or 1000 base t as you may use a switch which is more regarding of the cable quality.
regards,

Kripton2035 said:

...it should not work with a 100 or 1000 base t as you may use a switch which is more regarding of the cable quality.
regards,

Click to expand...

Hi Kripton2035,
But is depend on the applyed length of tis relative poor cable...
Typical web needs no more as so ca. 2 (ev. 10)MHz & it has often so 100KHz, than is signal quality on short distances not so a problem, but its to checkout......
K.

I understand that Kripton2035's differentiation between hub and switch based networks is actually meaning half-duplex
versus full-duplex communication. This makes sense, because crosstalk tolerance is different between both cases. Unfortunately,
I never saw a 100BASE-TX hub, although a HDX 100 MBPS link is basically provided as an option.

By IEEE 802.3, 100BASE-TX segments are limited to 100m (like 10BASE-T), but require CAT-5 cable in contrast to CAT-3.
I already mentioned, that I think todays telephone cables are almost equivalent to CAT-3. However, they aren't by manufacturer
specification, and they are surely considerably worse than CAT-5. So I doubt, that 100 m 100BASE-TX is reliable, if working
at all. But you should try.

As a side remark, PCs as well as hubs/switches have the basic feature of negotiating a link speed according to the
existing hardware. Unfortunately, the negotiation protocol is not testing the cable quality and completely performed at 10 MBPS.
So if you have a bad cable connection, that can't achieve 100 MBPS or achieve it with many transmission errors, the link
either fails completely or is effectively blocked due to permanent retransmissions. In this case, downgrading the setup of one
peer to 10 MBPS is the only way to connect.

>>"In this case, downgrading the setup of one peer to 10 MBPS is the only way to connect."

Or he trys experimenting with some defined impedances to known._apply some potentiometers/resistors in range of 100--700 Ohms as terminations, but maybe this is to complex? for him..
K.