[asterisk-users] Reliable wireless SIP phones

[Anselm Martin Hoffmeister]

Am Freitag, den 29.08.2008, 09:16 -0700 schrieb Ira:
> At 05:48 AM 8/29/2008, you wrote:
> >(so since they still liked the Snoms otherwise, my solution is to get them
> >to dial a star at the end of a number to select their 'home' account,
> >otherwise it goes out on their work account and the dialplan fixes it up)
> 
> We have 5 outgoing numbers we want to use selectively and we just 
> dial 1,2,3,4 or 6 first which picks the proper rules. If you forget 
> it asks which line you want to use and 1 is the line we want guests 
> to use so it all works fine if you don't know what's going on.

Hi,

on German landlines the user can pick a carrier on a per-call basis (at
least if it is a T-Com line). The national dialplan assigns 010NX and
0100NX prefixes for that purpose. I believe similar access codes are in
operation in US (10-10-XXX?), and possibly your system blocks those for
similar reasons as we do (they are useless on VoIP lines here). 

So those codes can be used for selecting a non-default line, where I use
"01099" to send out a call with my mobile phone Caller ID, "01090" for
anonymous no-callerid calling and 010[123][123] to select between three
providers with up to three outgoing Caller ID numbers each (and a few
others in the 010[4-8]X range). Not pre-pending such a number will make
a reasonable default choice here depending on the phone used. If the
percentage of non-default line calls is fair below 20% such a long
prefix is still better than dialing a digit before each number (with the
additional risk of forgetting that, or dialing that digit when calling
from other places.... :-)

This assures that guests have no trouble using the telephone, as they
just dial the phone number as they would from their own telephone at
home. If I want them to not have my caller ID on the callee display (no
call back, privacy, whatever) I simply tell them to "dial the 01090
first" - they will assume I want them to use a certain carrier, and not
need any additional instructions. "Call-By-Call", being the "German"
name for it, is widely known. 

Another aspect of carrier selection codes opposed to switching lines on
the phone is that it is independant of the phone hardware at hand, be it
an analogue + adapter, ISDN + adapter, DECT, SIP hardphone, software...

Of course it is not necessary to allow all prefixes from all phones, or
have the same meaning of a prefix on all phones (01099 here would be an
example that sends a different Caller ID from different phones,
depending of the mobile phone number of the person usually using that
phone).

Best regards,

Anselm
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/x-pkcs7-signature
Size: 3949 bytes
Desc: not available
Url : http://lists.digium.com/pipermail/asterisk-users/attachments/20080829/b956ff65/attachment.bin