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In our building, the demarc is on the complete opposite side from the network closet. So, the T1 is extended from the demarc with a CAT5E cable that runs across the building to the network closet and terminates at a RJ48X jack. From the RJ48X there is a thin, flat, network(? not labeled) cable that is run to the T1 modem/router.

We're switching to Comcast. Comcast installed the modem at the demarc. So, now I have to run from the modem all the way across the building with CAT5E. My question is, can I use the extender that is currently running from the T1 demarc to the RJ48X jack in the network closet to extend the cable modem?

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up vote 2 down vote accepted

I don't see why you couldn't. Just snip it off and put on an end or a jack of your own.

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Agreed. Just make sure that both ends are terminated identically. – joeqwerty Sep 21 '11 at 17:42
And make sure the two transmit wires are on a twisted pair and the two receive wires on a twisted pair. Wiring 1-1, 2-2, 3-3, and so on typically won't do this. – David Schwartz Sep 21 '11 at 17:49

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