[asterisk-users] International dialplans for Asterisk?

[Anselm Martin Hoffmeister]

Am Freitag, den 22.12.2006, 09:53 -0500 schrieb Doug Crompton:
> Wow what a mess! I can imagine how much easier it would be if the world
> adopted a country/area/exchange scheme like in the US with known length.
> It must be complicated in Germany just within the country. At least in the
> US we know what the length should be so if we don't have that we know the
> number is in error.
> 
> Doug

Having variable length offers several advantages, it just makes life
harder for telcos (and telco-lookalikes like us ;)

- Companies with several phones can have DDI, possibly multi-digit, but
(as convention) the "-0" always is the central phone desk. So if you do
not know the number of the person, but just the company (which would be
listed in the yellow pages), you call the -0 and ask to be transferred.

For example if I need to speak to the University library, I just call
73-0 (local call), and they transfer to extensions 73-1234.

I prefer this a lot over the system it seems the US as well as UK use a
lot, where you always dial a fixed-length number, the call is connected
(from which moment on you are charged for the call--- this was really
expensive if international tariffs applied) and a recorded message asks
you to dial a four-digit extension or "0" for assistance. I like our
system better, as it allows for all those nice "digital phone" features
like Callback-on-Called-Party-ends-call (if the remote side was on a
call, so the busy indication works without additional charge),
Callback-After-First-Call-Of-Remote-Party (where, if nobody was
available, the network will notifiy after the other side got off-hooked
and on-hooked again), and whatever there is.

- And then, in small populated areas that got their own area code
nonetheless, they handed out short numbers. Nowadays with ISDN lines
(which give you three up to 10 numbers) being so popular, VoIP
geographic numbers taking their share etc, the number room became full
in those areas. So they just took free 3-digit codes and made 6-digit
blocks out of them. No problem with digital switches on the telco side.

Here in Bonn (area 228) policy was that every new landline gets one
(analogue line) or three (ISDN) 7-digit numbers, and if you apply for up
to 7 more numbers, which was free until 2005, you would get 8-digit
numbers. Lots of 6-digit numbers are still in use (handed out until the
late 90s), shorter numbers do not exist except for companies. How short
a number they have (plus DDI digits) depends on what they pay for it and
how many channels their trunk has. They will get 5-digit(+x) here for a
reasonable price, 4-digit will be rather expensive, and 2-/3-digit are
not available any more - those in use have been assigned in the 50ties
when the phone system was built. So the University, the DoD, the D.of
Foreign Affairs, the town hall, the police central station... caught
them, and bad luck for all the others.

Of course, Germany does not have something like area-split and similar
hassles - at least not for technical reasons. AFAIK there have been a
handful area code changes for political reasons during the last 50
years, and the eastern part of Germany got a completely new phone system
after the Iron Curtain fell - quite foresight to keep the 3x area codes
unused in the western phone system (except 30 which is Berlin - but that
in fact is eastern Germany as well, obviously).

I think the most recent area code changes were when the 0-800 numbers
came, because some area had the code 8001 or so. European standards and
their popularity in germany, ahem... :)

BR
Anselm