On 2008-02-16 21:07:33 +0000, andrew@a17 (Andrew Gabriel) said:

In article 47b73fd7@qaanaaq,
Andy Hall writes:

Well the problem was that this was a product that had originated in the U.S.

For some reason, best known to themselves, BT had an addressing scheme
(group number IIRC) that was 4, while in every other country it was 0.
On this particular box the addressing wasn't configurable, simply
because there was no need anywhere other than in the UK.

Not too sure what you mean. PSS always required the DNIC to
be present (2342), whereas most other networks only required
the DNIC for calls to other networks. It was a bit like always
requiring the full international number to be dialled for a
phone call, even a local one. Actually, I thought this made a
lot of sense. Generally there's no one typing in X.121 addresses
for each connection (excluding dial-up PADs), so having short
forms of addresses was just overhead in software to recognise
(a bit of software I wrote a number of times in different
products;-). Since we sold in other countries too, we had to
cope with this though.

For the LCGN, PSS supported all 4 ranges if you subscribed to
them, although BT stopped selling new PVCs around 1985 because
their switches ran out of table space to record them. I can't
recall if other country implementations supported multiple LCGN
ranges (most didn't support PVCs, which would have removed one
of the LCGN ranges in any case).

You've stirred the cobwebs in the back of my mind on this one. I
did mean LCGN rather than the X.121 addressing.

IIRC, BT had 4 for SVCs and lower numbers for PVCs. This was an SVC
only product that went onto the market in about 1984 and in other
countries SVCs started at 0 so there was no need to have setting of
LCGN other than for the UK.