This topic

Full Fibre

Stewadg — Sun, 17 Jan 2021 12:00:03 GMT

Hi,

I've recently become eligible for full fibre broadband.

What does it involve in terms of running cables into house etc. I could do without major disruption.

TIA

Re: Full Fibre

pippincp — Sun, 17 Jan 2021 12:11:46 GMT

It involves running a fibre cable to your house and fitting an ONT inside. The clue is in the name, Fibre to the Premises.

Re: Full Fibre

Starwire — Sun, 17 Jan 2021 12:13:48 GMT

Means drilling several holes and if you’re lucky the Engineer might take pride in his work and make it look neat job, although those kind are very few and far between these days.

Re: Full Fibre

Stewadg — Sun, 17 Jan 2021 12:47:46 GMT

Thanks,

I assumed that, but BT website makes light of it and the guy on the online help said it wouldn't require any new cabling at all!

I assumed it would involve new cabling etc, so I'll give it a miss. maybe wait for wireless 5G to become established...

Re: Full Fibre

Gary_C — Sun, 17 Jan 2021 15:04:25 GMT

Its just a twin optic fibre, that comes in near your original POTS line.
The minimum bend radius means that the outside wall box is a bit deeper than maybe some expect, but Its not massive I believe (wating for mine to be installed in two weeks). I will report back on how it goes as mine is right outside the front door and I dont want a poor job.

Re: Full Fibre

Starwire — Sun, 17 Jan 2021 18:58:11 GMT

Twin Fibre Optic Cable?

Openreach don’t use Twin, aka a Pair of Fibres.

The newer Connectorised Fibre uses a single Fibre and the older Blown Fibre Tubing had a 4 Fibre Bundle Blown into the CSP but they only ever used 1 Fibre per OGEA Circuit and the EZ Bend Fibre from the CSP to the ONT was a Single Fibre.

Re: Full Fibre

Gary_C — Sun, 17 Jan 2021 22:50:32 GMT

Well, the cable sat outside my house coiled up ready for installation is a black figure of 8 style so I assumed it has a in and out fibre.

Not really looked into it. What type of fibre do openreach use ?, Mono or multimode step or graded index ?

Re: Full Fibre

pippincp — Sun, 17 Jan 2021 23:30:48 GMT

You assumed wrongly. @Starwire can possibly answer the rest.

Re: Full Fibre

Gary_C — Sun, 17 Jan 2021 23:40:07 GMT

So it seems..... thanks for that......
Still, small detail and doesn't change the point.
But will be interested Starwire, in more details. I did fibre transmission at Manchester and the Professor who gave the lectures was a bit of a curmudgeon to us lowly engineers (probably didn't help when I fell asleep in one 😉 ). Getting our heads around Modes caused us all headaches 🙂

Re: Full Fibre

Gary_C — Mon, 18 Jan 2021 20:48:27 GMT

Had a look at the cable and its definitely two 'core' figure of 8 style black insulation.

Re: Full Fibre

licquorice — Mon, 18 Jan 2021 20:51:40 GMT

Combined fibre and copper cable.

Re: Full Fibre

Starwire — Mon, 18 Jan 2021 20:52:26 GMT

Let’s see a picture of this 2 Core, or Pair of Fibres you’ve got.

Not heard anything about Openreach using such cable, there would be no point in it.

Re: Full Fibre

Starwire — Mon, 18 Jan 2021 20:56:17 GMT

@licquorice

I’ve not heard anything about Openreach using a 2 Core or Pair of Fibres.

Can’t see why they would.

As you said I suspect what he’s looking at is the Copper Pair in a Hybrid Cable.

Guess I’ll just have to wait a see if he uploads a picture.

Re: Full Fibre

Gary_C — Mon, 18 Jan 2021 22:39:38 GMT

Will try and get a better picture but

I think you can see that its two 'cores' joined (the second run down, you can see the dip between them)

It almost looks like 80's speaker cable !

Re: Full Fibre

spile — Tue, 19 Jan 2021 06:35:30 GMT

To give you an idea of the fibre/copper cable diameter, the Openreach engineer was able to use the existing hole in the brickwork. The Nokia ONT was fitted in the same place as the redundant Openreach modem

Re: Full Fibre

Starwire — Tue, 19 Jan 2021 06:41:33 GMT

That’s a Hybird Cable. The smaller side has a single Copper Pair in it and the thick one has a Single Fibre in it, not a Pair of Fibres or 2 Core as you say.

It’s the Connectorised Fibre Openreach have been using for a few years now on the Overhead Network, although it can also be used in the Underground Network as well.

They will soon be moving away from it though and just providing a Single Fibre with No Copper Pair in it for Overhead as well.

Re: Full Fibre

Starwire — Tue, 19 Jan 2021 06:42:53 GMT

I’ve got an O/H and U/G Provide today so I’ll get you some pictures of the cable sheathed down.

Re: Full Fibre

Gary_C — Tue, 19 Jan 2021 10:17:57 GMT

I see.
Having only really worked with FDDI type cable, I assumed it was twin fibre. I do remember at Uni discussing bi-directional fibre but it wasn't something that was realistic at the time (yes, it was that long ago 🙂 )
It will be interesting to see if I keep my phone line or move to VoIP as the order page didn't really specify.
Not that it matters as I believe POTS will be dead by 2025 ?

Re: Full Fibre

Gary_C — Fri, 22 Jan 2021 14:17:41 GMT

Well, looking at the cable, both 'cores' are the same size.

Just had a look at the cable ends.
Guess what ?

They are both optic fibres 🙂 (yes I have examined them with a high mag loupe)

Now its likely that only one core will be used as it seems the ONT will only expect one ?

Its a cable made by Corning optical tech Corning SMF bend insensitive fibre (BIF) but cant find the exact type from all the numbers on it, which are

CORNING OPTICAL CABLE
SMF BIF 5000865145 FASTACCESS <TM> TECNOLOGY
023518 FT

I see the fastaccess is about the ability to strip back the sheath make off the connection quicker and SMF I'm assuming from the Coring data, to be single mode fibre.

All a bit pointless, but fun to know.