[c-nsp] Extended demarc

[Pete Templin]

james edwards wrote:
> What is a real word limit on how far you can extend the demarc ? This is on
> Cat5e cable. I get wildly different figures from Google.

Late to the dance, so blame my vacation...

For T1s, Kentrox had a great white paper showing that you can go 
1000-2000 feet on Cat5 cable.  To go farther, up to about 6000', you'd 
need individually-shielded twisted pair cable (ISTP), to keep the 
transmit-motivated electrons from corrupting the wimpy receive-side 
electrons on the nearby pair.

pt