[asterisk-users] Extension Numbering

Michiel van Baak michiel at vanbaak.info
Fri Sep 29 17:10:09 MST 2006

On 01:35, Sat 30 Sep 06, Norbert Zawodsky wrote:
> And Hi again,
> I wrote:
> > I think I can remember something from the "Asterisk-TFOT" book saying
> > that one must not use 1-digit extension numbers. But I can't remember
> > that very well and can't find it in the book any more....
> >   
> I found it! On page 90 the book says:
> <quote>
> ... (Well, almost. Extensions must be shorter than 80 characters long,
> and you shouldn?t use single-character extensions for your own
> use, as they?re reserved.) ...
> </quote>
> O.k. - This answers my first question ("if there is disadvantage if we
> use only 1 digit extensions").
> But what for are single-character extensions "reserved" ?

a (*)
s (start)
t (timeout)
i (invalid)
h (hangup)
And maybe others, those come to mind right this second since
I use them a lot. They want to be sure they have 21 more
possible default available extensions.
That's why it's adviced to not use them to prevent trouble
with newer versions where your single-character extensions
clashes with some default builtin one.

For readability it's also better to use descriptive
extensions instead of singe character ones.


Michiel van Baak
michiel at vanbaak.eu
GnuPG key: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x71C946BD

"Why is it drug addicts and computer afficionados are both called users?"

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