So the ONT is fed by the green ended fibre - as it should be

The output is taken to the router which supplies the connection details via the ethernet cable plugged in next to it.

There must be an existing router plugged in somewhere else on the property making the connection and probably doing the current wifi.

It is the output (LAN) of this router you need to extend to the garage.

Well the ONT is 100% definitely connected to the incoming fibre. Refer to the second photo; the green fibre connector (SC/APC) is clearly visible.

Black cable with yellow connector is the ethernet cable from the ONT to the router.

So at least that is resolved.

Next up - confirming what cabling in place at the garage....

[cross posted with Zarjaz above]

Edited by Pheasant (Fri 22-Apr-22 11:44:50)

"It is the output (LAN) of this router you need to extend to the garage."

This is in line with what I would have expected and the easiest way is probably with a couple of powerline adapters which I can do.

My mate is convinced that the green cable was never there and it has been added as an output from the ONT and terminates in the garage in the RJ11 socket in the photo. From everything I've read here that's just not the case. I'm not going to worry too much about what's been done, like I say I can fix this for him with a couple of powerlines.

thanks for you help everyone

In reply to a post by heathmount:

"It is the output (LAN) of this router you need to extend to the garage."

… I can fix this for him with a couple of powerlines.

thanks for you help everyone

Powerline adaptors have mixed reports, some find them OK, others have many problems.

Just to be clear, the first photo is in the garage, and the others (with the ONT) are in the main house?

The RJ11 socket in the garage will have copper, not fibre, coming out of the back. Most likely it's a phone extension.

If it's two-pair telephone cabling then you really shouldn't use it for data. It may work at 100Mbps, if you wire the two pairs correctly to RJ45 plugs (pins 1+2 on one pair, pins 3+6 on the other pair). But you'd first need to find the other end in the house - and it most definitely isn't the Openreach incoming fibre with the green connector!

Your idea of powerline sounds fine, as long as both buildings are fed from the same consumer unit, and doesn't cost too much to try.

In reply to a post by heathmount:

https://www.flickr.com/photos/52428889@N03/52021864800/

Out of interest what is plugged into the socket on this picture?

"Just to be clear, the first photo is in the garage, and the others (with the ONT) are in the main house?"
Yes

"Out of interest what is plugged into the socket on this picture?"
An RJ11 cable into a second router. There's been no work done on this second router to disable DNS, assign a static IP address etc. However even if this had been done it sounds like it would never work. Sounds like "something" has been run into the garage but not something that will work. I'll be round there this weekend to sort out the powerline method.

Possibly a builder with no idea what they are doing has run a phone extension and said "plug another router in here".

Your best hope is that they used a Cat5e cable to do it.

In reply to a post by jpm:

Your best hope is that they used a Cat5e cable to do it.

Eeeh yeah; sparkies and data cabling is bad enough....but builders. Shudder.

For the OP - If there's enough slack in the cable behind that plate, they could be re-terminated onto RJ45 jacks/sockets. Would need a suitable replacement faceplate to be fitted, but fairly straightforward.

On the other hand if the builder has just plonked into CW1308....give up now and try a pair of powerline adapters or possibly run in a new 4-pair Cat5e/Cat6 cable or two.

My mate is convinced that the green cable was never there and it has been added as an output from the ONT

Best insist your mate stays well away from it all then, most especially that incoming fibre connection. They are reasonable robust, but getting the ends dirty or scratched can cause issues.