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Old September 11th 17, 09:53 PM posted to uk.telecom.broadband
Graham.[_3_]
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Posts: 158
Default "Bridge Tap" on the BT Wholesale Availability Checker

On Mon, 11 Sep 2017 16:27:08 -0000 (UTC), Andrew Benham
wrote:

The BT Wholesale Availability Checker
https://www.btwholesale.com/includes/adsl/adsl.htm
now has a field under "Premise environment" for "Bridge Tap".

The status can be either "U" (for unknown ?), "Y", or "N".

If I check phone numbers where I know there's no DSL, the
status is shown as "U". If I check my number the status is
shown as "N" - good, I have VDSL, and I've made sure there
are no bridge taps. I don't know anyone who has VDSL with
bridge taps, so I can't check for "Y".

But I don't know what status is reported on lines with ADSL
on them. Aren't bridge taps purely a VDSL issue ? So do
lines with ADSL on them have a status of "U" ? Or does the
BT Checker notice bridge taps on ADSL lines as well as VDSL
lines ?

A friend of mine recently upgraded from ADSL to VDSL and
his status went from "U" to "N". But other numbers I've
tried have statuses of "N" and "Y" - where I think the line
is still only ADSL.


Bridge taps are a Bad Thing (tm) on a line carrying any flavour of
DSL.
They were used as an economy convenience, a given line had drops to
multiple DPs on its way. Only one subscriber would be connected, but
the line could be re-allocated to someone else with less redundant
cable plant.

I always imagine them being used in rural areas where the farms and
houses are widely spaced. Just the sort of area where VDSL might not
be available.



--

Graham.
%Profound_observation%