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.