Hi Paul.
>> Is the network connection using BNC cable or twisted pair
>> cable? If BNC cable, you can stop here as the rest of this
>> doesn't apply, but please let me know so I know to ignore
>> this as well.
> I'm using twisted pair.
>> Assuming the lead uses twisted pair cable, is it going
>> directly between the two computers, or are there separate
>> leads from each computer to a hub?
> Each computer is connected to a hub.
That's the exact case where I met this problem...
>> Also, did you make the cable yourself from scratch; is it
>> one you've bought in that's unmodified; or is it one you've
>> bought in that you've shortened?
> No the cables were premade and were included in the network
> kit.
In that case, you're going to hate what I'm about to say, but as
a quick summary, you probably have a faulty cable.
The required connections are symmetrical in this case, but
there's no easy way of checking that they are completely correct
other than taking the plug off one end and remaking it.
The cable used is called "Twisted Pair" because it comprises four
separate PAIRS of cables, and the members of each pair are
twisted together along the whole length of the cable. The two
wires that form each pair are also colour coded, one comprising a
solid colour, the other being white with bands of that solid
colour.
Unfortunately, as the wiring isn't quite what one might at first
assume, it is quite common for two of the wires that are white
with a band of colour to get swapped over. The result of doing so
is that the cable only works in one direction, which is exactly
what you are seeing.
If you hold the cable up, and slip the hoods (if fitted) off the
plugs, you should find that the plugs themselves are transparent.
Hold them side by side with the tab away from you, and you should
be able to tell where the four wires with solid colours connect
to. The pattern you should see is as follows:
1. One of the solid coloured wires goes into one of the end
connectors. The matching white with coloured band should
go into the adjoining connector at the same end.
2. Another of the solid coloured wires should go into the
second connector from the opposite end. The matching
white with coloured band goes into the adjoining end
connector.
Those two pairs are exactly as you might expect. Unfortunately,
the other two pairs are not...
3. If you look at the third connector from the first end, that
should also have a solid coloured wire going to it. However,
the matching white with coloured band wire does NOT go into
the adjoining connector, but to the third wire from the
second end.
4. Finally, the fourth wire from the second end is the fourth
solid coloured wire, and its matching white with coloured
band is the fourth wire from the first end, thus adjoining
it on the WRONG side.
I would suspect that one of your cables has the two white with
coloured band wires referenced in (3) and (4) above swapped
over at ONE END ONLY. If so, you will need to return the wire in
question to the shop you bought it from and get it replaced with
a good one, or alternatively to strip the connector off and
rewire it correctly. Unfortunately, the pliers needed to rewire
those connectors tend to be expensive.
Best wishes from Riley GM7GOD / KB8PPG.
---
* God Made 7 Greedy Old Devils
* Kilroy Bought 8 Personal Pregnancy Guides
