Connecting RJ45 cable with fiber
christophe -
Hello, I'm soon getting fiber optic internet, but to make the most of it, I would also like to have an "RJ45" connection upstairs. Currently, in the living room, I have my box (connected to a phone socket). In two other rooms, I have two phone sockets that won't be of any use to me, and upstairs, I have one. I was told that it couldn't carry ADSL, only phone ("RJ11" or something like that). So, some adjustments are necessary.
I'm not sure I understand how a wired network is organized in a house, but I'm supposed to have a "DTI" or some sort of central hub that connects the phone sockets to each other? There's nothing in my garage, but maybe behind the circuit breaker? Maybe I don't have one, but they are still interconnected? I imagine that during installation, the phone socket in the living room will be replaced by the fiber socket. So, if I want to connect the box, I need to connect an "RJ45" either to the "DTI" if there is one, which will itself be connected in "RJ45" instead of the phone socket upstairs. Or, there might not be a "DTI". In that case, I would need to use another socket. Next to the phone socket of the box, there is a TV socket that is of no use. I will convert it into an "RJ45" socket and run the cable up to the second floor, then connect the box to it. However, the TV socket and the phone socket upstairs are likely not related, so they probably are not linked (I don't know how a domestic electric network is set up, but there should be a place where all the wires converge at the circuit breaker, probably). From there, I will run the cable and bring it upstairs.
I don't know if it's useful to mention, but the house is about fifteen years old.
17 réponses
Hello,
You indeed need to find the starting point of the cables that supply the telephone sockets. In a house about fifteen years old, there should be a DTI or at least a strip or terminal block with 8 or 12 terminals: https://www.elec-boutique.fr/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/0/3/034200_p_87931_pcat_1.jpg
The cables arrive at a central point, often next to the electrical box or in an adjacent box.
The cables for telephony are indeed connected together, but this is not what is needed for Ethernet. At the communication box at the end of each cable, you need to install a female RJ45 socket, the patch panel, and replace the telephone wall sockets with RJ45 sockets.
This is possible if the cables used are 4-pair cables (8 wires), so it needs to be checked by finding the central point of the telephone network or by opening a wall socket.
Are your telephone wall sockets T-jacks or something else? You mentioned RJ11?
With the arrival of fiber, the question of where to install the fiber inlet arises. Logically, within a network in the home, it should be installed in the communication box at the start of the sockets that supply the residence. But there indeed needs to be a functioning network. Because if it is in the living room, to distribute the network you need to use a wall socket to bring the network down to the communication box to distribute it to the other rooms.
Yes, these are T sockets; only the one in the living room is used to connect the box, and the one upstairs that I want to link cannot carry ADSL, only phone. So since the TV socket and the T socket are both network-related sockets, they should have a common connection point, allowing for an RJ45 cable to be run. Is the box necessarily inside the house? (I am connected from a pole that goes to a little white box (I haven't observed it), and then the wires go underground to reach the house. Is it possible that this is where I need to make the connections? Or is there something else necessarily in the house, the communication cabinet? And if I don’t have a communication box (which I believe is relatively expensive), simply plugging the box into the TV socket modified for RJ45, which is connected to the socket upstairs, is not possible; am I obliged to have a box?
Hello,
the proper organization of low current wiring in a house is as follows:
Everything above, including the patching, is at the communication cabinet, the coaxial TV splitter can be omitted.
The ideal would thus be to install your patching and wall-mounted RJ45 sockets before the arrival of the fiber and to bring the fiber to the communication cabinet.
The DTI will no longer be useful, basically replaced by a DTIo also called PTO.
Fifteen years ago, electrical panels in the GTL were already mandatory and communication cabinets too, it seems to me. DTIs were also systematically installed.
Now with the arrival of fiber, the DTI will no longer serve any purpose and can be removed.
And there you go, voilà ....
But what a pain the line spacing is !!
There is only one cable coming for the phone line. Somewhere there must be a box that connects this cable to the 4 cables that correspond to the wall phone sockets.
Open a wall phone socket to see if the cable has 8 wires, to check if the cable can be used. If it cannot, you will need to run network cables through the house, which can be simple with well-made conduits or impossible.
The TV cable cannot be used. You could just use it to pull a network cable through the conduits. By the way, TV cables usually have a central point where the cable from the antenna arrives to distribute to the rooms. This central TV point is most often placed with the central phone/network point.
Furthermore, you need to think about where to place the fiber box, and how the fiber cable is going to reach the box. Often the path of the phone cables will be followed, so you also need to know where they end up.
But the T socket in my living room will have to be used for the fiber that powers the livebox (the fiber box will be in the living room, right next to the box (I think that's best), but there won't be more sockets to run an RJ45 to the box/power supply. (By the way, do you know how I could find it? I've searched everywhere but I haven't found anything. It can just be cables linked together?)
All right, but does that mean the RJ45 cable connections come from the box and not from the cabinet? (And do they have to go back through the intersection point of all the wires then?)
Can the cabinet be hidden behind the circuit breaker? (My circuit breaker has cover plates, maybe it's located under one of them?)
Does the cable installation need to be done by a professional, or can I do it myself? (Is it complicated?)
No, the communication box is not hidden; the DTI test socket must be accessible.
However, if it’s a 12-way strip (it shouldn’t be that way if it’s 15 years old), it may be located in the attic or near the ceiling.
Low current sockets and cables do not require professional intervention; the difficulty can be quite significant if one lacks the experience to pull cables through the conduits.
I think that if there was a box, I would have seen it (I have the green Linky circuit breaker with the thing next to it) and another circuit breaker for the rooms; this one is relatively big and it is on a sort of column/recess in the wall (probably the cables go behind it). It consists of 4 "plates" made of plastic, with rows of buttons to disconnect areas on the first 3, and on the last one, there are no buttons/circuit breakers, only two standard sockets. Maybe by unscrewing this plate, we could find what we are looking for behind it?
Hello,
It is important that you find out where the ADSL line reappears in your house, as the fiber will follow exactly the same path from the telephone pole to the inside of the house.
Where is your electrical distribution box? In the garage? The arrival of the telephone cable and the DTI should be nearby (often on the same wall) if it is not in the electrical distribution box.
Very difficult to catch a black cat in a dark room.
Especially when it's not there...
Give us some photos. If you have a block, separate from the current circuit breaker block, like block No. 3 from the link provided by @brupala, with its 4 large plastic screws, open it.
It's the same, there are 4 plastic fittings underneath but the "3" (these are communication box bits that stick out in the photo except mine just has 2 standard electrical sockets. But otherwise, it's exactly the same as in the linked photo) and on the other hand, the 1 (the subscriber circuit breaker panel) is located next to the Linky meter)
(I tried the photo but you can't see much)
So should I open it or not?
For the components, no worries, the cable is bare, there should be a rail, we add female RJ45 sockets to the rail. https://www.amazon.fr/kwmobile-Module-Keystone-RJ45-Cat/dp/B08HQGWV7X/
The fiber installer will ask you where the telephony arrives, you should open the box to check, and see if the TV output is there as well.
We can use the TV cable or the phone cable to pull the fiber cable, but for the future, it's a bad idea. Otherwise, we need to try to pass both in the same conduit if it's wide enough.
There shouldn't be a conduit going from the living room to the first floor; all conduits should go towards the communication box. So to go from the living room to the first floor, we return to the initial solution: find the communication box and connect the living room/first floor cables with a bridge.
Is using the TV duct bad? I don't know if the TV cables typically go through the box (maybe there aren't even any TV cables, just sockets since I've never had antennas). If possible, the idea is to run the fiber through the TV cable duct if there is one, and the new RJ45 cable through the telephone line duct of the ADSL (but a new, more powerful RJ45), and then into the area of the box (but without going directly through the box) the RJ45 cable goes straight up to the floor. And as I said, if the TV duct isn't there, we run the fiber through the same duct as the RJ45 (if possible), and then finally we run it to the TV socket next to the RJ45 socket.
I'm not sure if I was very clear in my remarks, I apologize.
Is it better to make the RJ45 connection before or after the fiber installation?
As already stated and reiterated by jee pee, the problem lies in the fact that the fiber will arrive at the same location as the telephone cable coming from outside.
This cable, as already mentioned, certainly arrives at a DTI box and from there is distributed to the rooms of the house. Therefore, the fiber will not be able to use the conduit that currently brings the ADSL signal to the box via the telephone socket in the living room. To find the telephone cable that goes to the living room, one must theoretically locate its starting point, which is the DTI (or a 12-terminal box).
If you do not know where the incoming telephone cable from outside is located in the house, the technicians who are to install the fiber will not do anything until you indicate to them where their fiber cable will exit...
Very difficult to catch a black cat in a dark room.
Especially when it is not there...
The cable arrives at the box, but once at the box, there is necessarily a sheath that leads to the telephone socket from the box, so once the fiber is at the box, all that’s left is to follow the sheath leading to the telephone socket? I may have misunderstood something about the organization of the cables from the DTI?
Well, I managed to open it. I didn't take any photos because it was too dark and you couldn't see anything, but I could take one during the day if necessary. So there are lots of cables and a phone socket labeled DTI TEST; however, I didn't see any wires connected to a common switch or anything, just some connected to the kind of phone socket. Then it went into the column behind.
But there was still some kind of horizontal plastic plate with little green and red plastic bits and a few wires connected to it. But nothing that looks like RJ45.
We can't see much in this fog ... :-(
But we can still make out a couple of connections to your phone lines, so we can assume they lead there.
You can step back a bit and frame a little wider for your photos, no need to do macro.
Is that good like this? Otherwise, I’ll go redo it tomorrow during the day when it's easier to see. By following these wires, we can reach the outlets, but it then goes up in the column; it must go into conduits, I imagine? With a pulling needle, I’m going to struggle to find the right conduit, right?
Your setup there is only for telephony. This is regularly what we encounter on the forum.
Most of the time, to make an Ethernet network, we use the existing cables. We only touch the wall sockets, and there in the communication box at the end of each cable, we put a female RJ45 socket. Therefore, to connect the living room to the first floor, we put an Ethernet cord between the socket coming from the living room and the one on the first floor. We do not pull any new cables.
There, the photos do not allow us to determine how many cables are arriving at the DTI. But you can tell us how many wall sockets there are in the house. And the photo does not allow us to determine the type of cable, particularly if they are indeed cables with 4 pairs (8 wires).
Only one telephone socket is used, the one connected to the box. The other unused sockets and the one upstairs are only for the telephone but not even ADSL. That's why my idea (as repeated above) was to no longer go through here. To bring the fiber into the living room through the conduit of the telephone socket that arrives in the living room and then run a cable from the living room to the bedroom without connecting to the telephone thing.
Your cabinet looks narrow; if there's a TV connection, there should be a TV splitter, like my link above, with as many outputs as there are TV sockets in the apartment.
If it exists, it might be at the back, behind the DTI or the electrical sockets. The latter, in this box, don't simplify things. And since your photos don't clearly show the foreground, the background is likely to be worse.
Okay, so the best thing to do is to wait for the installation to be done while asking the technicians where such duct is located, and then I’ll see where to run the cable?
(However, if there is already fiber in a duct as I suggested earlier, running another cable will be complicated at the risk of damaging it?)