Spetznaz

All the FTTC cabinets are connected to equipment in a 'Headend exchange' or 'Handover point'. This is not always the local exchange. Originally there were planned to be around 1000 of these, ( out of 5500 in total), these are where the responsibility is passed from Openreach to the ISP/Wholesaler for the service. The new cab, oitside the exchange, will just piggyback on existing fibre that exists between exchanges to get back to the Headend site.

21CN infrastructure will exist at these exchanges but may not at the local exchange. There are now several thousand exchanges with FTTC that do not have WBC/ADSL2+ from BT and about 1000 that do not have an LLU operator in that would provide ASDSL2+ services. Yours is one on these.

TalkTalk has ADSL2+ in the most exchanges but BT is rolling out to additional ones slowly, they may be using recovered 21c DSLAMs from places where FTTC and LLU has reduced ADSL2+ workers to the point where some DSLAMs are no longer required.

There is not much point in upgrading to ADSL2+ if you have the option of FTTC. (Unless you are a long way from an FTTC cab where it can give a better service even though the Cab is closer to you)

Roberto

If the exchange has fibre existing to serve the rest of the services ( 90+%) they will either connect to it in the 'Exchange manhole' just outside the building ( enabling the building to be sold off at some theoretical future date) or connect to the existing transmission equipment inside the building.

If it didn't have fibre before, it is likely that the new fibre would have been run in (or alongside) the existing duct to the building before branching out to the seperate Cabs. Only where the cabs are already on a route from another exchange would they be connected direct to the other exchange.

Existing duct ( or overhead route) is always cheaper than providing new.

Quite . We have no idea about the specific exchange, which I was talking about. Not that I had no idea about the alternatives.

Its the best way forward, everyone on BTw would gain, however the obvious issue is LLU ADSL customers.

The estimate of 20mbit seems about right to me, although this depends on the distance between cabinet and exchange, if cabinet is close to the exchange the power cutback is very low and way less than 20mbit is lost, if its at the distance my cabinet is, then power cutback is heavy and circa 15-20mbit is lost. If its really far out tho then less tones will be affected and its not quite as bad although still worse than the cabinets very close to the exchange.

The problem is if BTw only lines moved to the cabinet they would still need power cutback to protect ADSL LLU lines, LLU providers are stuck in the exchange for ADSL services.

Either LLU providers would need to move dslams to cabinet.
LLU ADSL is removed as a product (angry LLU isp's would never happen under ofcom).
Or the D side FTTC lines are all seperated from ADSL lines, so no crosstalk. (openreach wouldnt do it due to expense).