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Ethernet & Phone Line Switch Setup in New Home with Comcast Internet not working?

Last response: in Networking
October 4, 2013 10:51:21 AM

I just moved into a new home with what looks like a main switch for ethernet and phone lines to each individual room. However, I can’t get the switch to work with my new Comcast cable internet.

Internet works with:

(main line > modem > computer)
(main line > modem > router > computer)
(main line > modem > router >(wirelessly) computer)

but not with

(main line > modem > switch > computer)
(main line > modem > router > switch > computer)

I’ve never used a switch before but I assume the cable goes from the modem to the “IN” of the switch, with a cable from one of the outputs to computer, unless I’m wrong.

Here’s are some images:

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October 4, 2013 11:00:19 AM

Without knowing more about the house wiring, it is hard to say.

But generally how it works is:
ISP -> modem -> router -> devices*

* Devices may include one or more switches, and computers hanging off of that.

(main line  modem  router  computer)

should work exactly the same as this:
(main line  modem  router  switch  computer)
October 4, 2013 11:04:31 AM

It SHOULD but it doesn't work. Is this home system any different from a typical consumer switch? I connected the ISP line to "IN" (as shown in picture). I thought it was as simple as that.
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Best solution

October 4, 2013 11:14:23 AM

OK - did not see the images initially

The 'Telephone Interface Module', with the "In" appears to be the phone/alarm system, NOT ethernet.
RJ31 is generally for alarm systems.

You would go thusly (I think):
Modem -> router -> existing 8 port 10/100 switch (middle image) -> other devices plugged into that switch.

Whoever wired this should have supplied a detailed schematic of exactly what it does. I'm in the middle of planning the wiring of a house, and whoever gets it next will have a full schematic of where everything is.
October 4, 2013 11:17:00 AM

^ +1. The IN is on a telephone interface, not the Ethernet switch. Some older home networks can be loads of fun to figure out. An Ethernet tester is quite helpful.
October 4, 2013 11:17:42 AM

Oh... let me give that a try. Thanks!