How does FTTC get connected to individual subscriber line

I was having a look at this picture of an FTTC cabinet and had some questions that someone will know something about.

On the photo I can see the fiber coming in from the bottom on the right hand part and being connected to the DSLAM in the left. Single fiber?

The gray cables coming in on the bottom right are, I assume, the phone lines coming in from the nearby CAB, which look like they're then connected individually for each subscriber on the right? Then this is all sent to the left hand part of the cabinet where the DSLAM is housed?

How the heck does the OpenReach engineer know which pair belongs to which property?

Can anyone enlighten me? I'm fascinated by this kind of stuff.

Thanks
Tim

http://www.coolwebhome.co.uk/fibre-cornwall/ has the rest of the pictures

Eight fibres head over the DSLAM side, but only one appears in use.

http://www.coolwebhome.co.uk/fibre-cornwall/images/f... is the exchange side of all this, where the FTTC and FTTP come together and is handed other to BT Wholesale and LLU operators

As for how the engineers identify the pairs, I'll leave one of them to explain

The engineer connecting the premises to FTTC does not (have) access (to) the fibre cabinet.

The connections you see there are to a corresponding patch panel in the PCP. The installing engineer connects the E-side and D-side for the customer to that patch panel. Job done.

Only a limited number of links between the two cabinets are initially installed, by the commissioning engineers. More are added if needed due to takeup.

The e and d side terminations in the PCP are recorded centrally, but the installation engineer will double check they have right pairs to begin with. The pairs to/from the FTTC cabinet are (should be) pre-connected in FTTC cabinet and correspond to a VDSL port in the FTTC cabinet. The installation engineer is given the pairs to connect the E nd D side terminations to. All being well there should be continuity when everything is connected through.

Edited by deleted (Mon 19-Nov-12 18:38:12)

What an educational trip that must have been!

Thanks to these photos I can understand what D-side and E-side means... for example.

Tim

So did the E-side and D-side exist in the PCP before FTTC?

So for an FTTC install the installing engineer contacts the end user. Disconnects the subscribers line from ADSL panel at the Exchange. Goes to the cabinet and joines the E-side to the D-side (which he's been given by some computer?) and then goes and installs the CPE?

That makes much more sense than how I'd imagined was done. Thank you guys for explaining the basics.

Thanks
Tim

In reply to a post by timl:

So did the E-side and D-side exist in the PCP before FTTC?

Yes it's where both interconnect

In reply to a post by RobertoS:

The connections you see there are to a corresponding patch panel in the PCP. The installing engineer connects the E-side and D-side for the customer to that patch panel. Job done.

In most of the PCP's where i live there are not patch pannels the corresponding E &D pairs are connected by only Gel crimps if there is any pannels in them it's for pair id only

I kind of get this and I don't.

D-side is from the end users house?
E-side is from the exchange?

Won't these already be connected? Or does the line get patched to the FTTC box which then takes the broadband locally through VDSL2 and passes the phone line back to the exchange at the same time?

Thanks
Tim

In reply to a post by timl:

I kind of get this and I don't.

D-side is from the end users house?
E-side is from the exchange?

Won't these already be connected? Or does the line get patched to the FTTC box which then takes the broadband locally through VDSL2 and passes the phone line back to the exchange at the same time?

Thanks
Tim

With no FTTC the PCP is just a termination point for the E and D pairs Where there is a FFTC cab installed There is a Tie pair link cable that allows the 2 to be connected , So when you subscribe for an FTTC service the E side is connected to the PTSN part of the cab,(Via the tie pair link) any Dsl signal is filtered out , Then from the FFTC cab you get VSDL2 and PSTN services on to the D side pair , So if you have a Bad E side , then this won't affect vdsl2 Because the vdsl 2 signal is delivered via the fibre optic cable from exchange

And yes E side =Exchange D side =PCP >< line box >NTE5A

Edited by tommy45 (Mon 19-Nov-12 20:11:14)

Forget about FTTC for a minute. There has always been the E-side, which is multi-pair cable(s) between the exchange and the PCP (Primary Connection Point) cabinet, and the D-side which is smaller cable heading out to the premises that are to be serviced. At various points on the D-side there are junction boxes where lines to telegraph poles or to individual premises are split off. (There are usually bigger E-side junctions as well).

When a premises is first supplied with a phone line, the engineer is told the ID of a spare e-side pair in the PCP. He connects the feed from the premises to that. Probably with gel crimps as described by tommy.

For FTTC that connection within the PCP is broken and the e-side is fed to the FTTC cabinet via the (new) patch panel. The connections between the patch panels in the two cabinets are made at the time the kit is installed, as I explained in my previous post.

The DSLAM in the FTTC cabinet combines the phone signal with the fibre optic feed from the exchange to itself and feeds it back as phone and VDSL2 signals on a single pair to the PCP patch panel where the D-side is connected . I assume the engineer is told the port to use at the PCP patch panel.

See this more detailed explanation.

(You may not kow that on ordinary broadband, (ADSL/ADSL2/ADSL2+), the phone and ADSLx signals are combined by the DSLAM at the exchange in an equivalent setup).

In reply to a post by tommy45:

In reply to a post by RobertoS:

The connections you see there are to a corresponding patch panel in the PCP. The installing engineer connects the E-side and D-side for the customer to that patch panel. Job done.

In most of the PCP's where i live there are not patch pannels the corresponding E &D pairs are connected by only Gel crimps if there is any pannels in them it's for pair id only

You're confusing things .

For pure PSTN supply I agree most connections are gel crimps. However for FTTC the connection between the two cabinets is via pre-connected patch panels. Clearly the e-side and d-side pairs can need something connecting to them (with gel crimps) to reach the PCP patch panel, but I assure you it is there.

That's fantastic thanks to everyone I understand the basics. You''re all amazing.