Lines connected directly to the exchange

Why is it that Infinity is not offered to those with lines connected to the exchange.

I presume the fibre is present at the exchange, so if there are a sufficient number of connections direct to the exhange why is the necessary kit not fitted in the exchange to service these customers. I don't understand.

Could someone please give me an accurate reason why this is not done.

Only BT decision makers can give an accurate reason.

In cornwall they talk of an unnamed solution that is not fttp or fttc

In terms of getting the biggest bang for the Openreach buck, lines which are connected directly to the exchange tend to be short and their users have less to gain than those on long lines with slower speeds. In time you may be offered FTTC style performance, or as you are close to an exchange, maybe FTTP.

The reason that BT do not provide FTTC on exchange only lines is because VDSL2 is not allowed inside the exchange because of the "band plan" used by BT as to what you can and can't do.

It could also cause complications in splitting off the VDSL2 signals at the frame and directing them to a VDSL2 DSLAM and then from there to the equivalent of the fibre connection that others are coming on. For a very small number of lines (as a percentage) this non-standard solution would be expensive.

The answer in the longer term is to install a cabinet which is "logically" outside the exchange (even if it is physically inside) or install a "real" cabinet immediately outside.

The other option in the longer term is FTTP.

And, of course, exchange only lines are not always short.

In reply to a post by MrSaffron:

Only BT decision makers can give an accurate reason.

I thought the ANFP prohibited it, and the ANFP wasn't set by BT or OR ??

ANFP is irrelevant if you are deploying FTTP

On the ANFP while other bodies have input, BT is a massive driver due to the amount of RnD they do, e.g. have been playing with VDSL for many years and are involved in world standards too.

In reply to a post by MrSaffron:

ANFP is irrelevant if you are deploying FTTP

Understood - I was thinking FTTC

On the ANFP while other bodies have input, BT is a massive driver due to the amount of RnD they do, e.g. have been playing with VDSL for many years and are involved in world standards too.

Ah... thanks.

The ANFP is a document that defines what frequencies can be used in the Access network (ie all the copper lines) in the UK. It has to be met by anyone that wants to connect into BT's network (or KCOM's network, with a different version of the ANFP).

The body that defines the ANFP is the NICC, which sets the standards, but is a committee that works under the auspices of Ofcom.

The ANFP defines that the frequencies used by VDSL2 (ie the variant of DSL used in FTTC) can only be generated from the cabinet in the street, and not the exchange building itself. It doesn't specify why this is the case, but it is undoubtedly to prevent problems in interworking with the other equipment located in the exchange building, or to prevent interference for customers who use ADSL from the exchange (which may be BT or an LLU such as Sky).

The ANFP used to allow up to 7MHz from the cabinets, but has recently changed to allow up to 17MHz. As someone else has mentioned, it is the BT R&D department that will have a big input into the committee's decisions about what is workable within the access network.

So... The restriction in FTTC comes from Ofcom, delegated to a sub-committee, under guidance from BT engineers.

The restriction in FTTP is ... probably ... a mix of financial restriction, plus a general wariness because the techniques for deployment of FTTP are not as mature as those for deployment of FTTC.

IMO the best that people on Direct-Exchange lines can hope for is that BT get a good take-up of their FTTx products, which makes them reconsider deployment out to more & more of the "not-quite-standard" subscribers.