CAT3 cable is twisted, just not as much, but it's only rated for 10 MB, not 100 MB. It may work for short distances, like for a temporary patch cable replacement, but I wouldn't use it for anything permanent. 6 months from now a simple change in the environment could give you all kinds of trouble, and you might not relate it to using CAT3 instead of CAT5/CAT5E cable.
Not worth the difference in cost.
The flat untwisted cable often used for connection a phone to the wall would not be reliable at all.
You'd have to use the RJ45 connectors. The 4P4C will plug into an RJ-45, but connects to pins 3,4,5,6. Any Ethernet device uses pins 1,2,3, and 6, so that won't work.
Microsoft MVP - Windows Expert - Consumer
Of course I know all the answers; I just don't always match the answers to the right questions.
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