longtime reader first time poster. I just moved into an apartment with in-wall Cat 5e wiring, and I'm hoping someone can shed some light on what I found in the box where they all come together. See photos below. In short, there appears to be a punchdown patch panel, but there are no RJ45 plugs on it. The grey Cat 5e cables come in through the wall and appear to be punched down vertically (first photo), with a blue Cat 5e cable that crosses all of them horizontally (second photo). There is nothing on the back of the panel, just the metal frame.

Then there is some kind of wacky splicing of one blue Cat 5e cable and one grey one (first photo again).

I have no idea how to connect a router to this or even what's supposed to be happening here. I am wondering if I should just replace the patch panel (if that is in fact what it is) with one that has RJ45 ports I can plug a router into. But I don't know much about in-wall network wiring so worried I'm missing the logic of this setup somehow.

Any light that anyone can shed on this mess would be appreciated.

I'll note that I suspect the contractor didn't know what he was doing, because instead of using the 8-way coaxial splitter in the module there to supply signal to all of the coax jacks in the apartment, he used a 50-cent 2-way splitter and left the rest of the coax cables in the box unterminated and disconnected.

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  • Is this a rental unit and is this box in the unit?
    – JACK
    Commented Jul 27, 2021 at 3:16

1 Answer 1


Terminology and telecom background

This box as a whole is called a "structured wiring panel."

The vertical blocks are called "110-style" connectors, terminals, etc. As you noted, one cable bridges across all the terminals. This is a normal configuration for wiring used in "POTS" analog telephone service.

The blue shrink-wrapped connectors making the splice between the gray and blue cables are called "B connectors." They're all spiky inside so that, when crimped, they pierce the insulation and connect the conductors inside them. The yellow tape is marked 332 7109 on one and 332 7007 (maybe?) on the other. Those are probably the telephone numbers that were in service here at the time the wiring was last touched.

Using a 2-port coax splitter when only two ports require signal actually does make sense. The power of the cable TV signal is cut in half each time it goes through a 1-to-2 split. An 8-to-1 splitter is just a cascaded set of 2-to-1 splitters, so the power coming out each port is 12.5% of the input power -- if a single 1-to-2 splitter is used instead, those two outputs each get 50% of the input power. It's good practice to avoid splitting more than is necessary.

What you really wanted to know

  1. Yes that CAT5e wiring could be used for Ethernet, but it isn't currently set up for that.
  2. This end would typically need an RJ45 patch panel with a port for each cable.
  3. The wall jacks in the other rooms likely need to be changed from telephone style RJ11/RJ12 (4P6C/6P6C) to Ethernet style RJ45 (8P8C) modular jacks.
  4. This work needs to be done carefully, ie in a way that preserves the length and condition of the in-wall wiring so that the wiring isn't spoiled (such as becoming too short to reach into the wiring panel sufficiently for future use).
  5. You mentioned the word "apartment" which to me implies you don't own the place. If that's correct, be sure to get approval from property management before making changes. If they noticed your work during move-out inspection it could be bad news for your wallet.
  • Thanks Greg! I was thrown off because all of the jacks in the wall are the larger Ethernet type ones and are labeled Cat 5e, so I was assuming they were set up for Ethernet, not telephone. I guess now the question is how to replace the connector that's currently in there with one that does Ethernet. The structured wiring panel is from Futuresmart, which appears not to exist anymore. And I gather the connector modules aren't a standard size, so a module from another company may not fit. Do I need to replace the whole panel?
    – dlitter1
    Commented Jul 27, 2021 at 13:10
  • @dlitter1 Simply relax your thinking a bit. :-) This is low voltage data - no need for choosing accessories that are UL-listed for the panel like we would do in a circuit breaker box. Choose any patch panel that physically fits in the box. Make a mounting bracket if needed, and/or physically modify the patch panel or the box to make it all work together. It's not unheard of to hang the patch panel with zip ties even. Or use several 2-port surface-mount boxes to hold the RJ45 keystone jacks.
    – Greg Hill
    Commented Jul 27, 2021 at 16:43

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