Iñaki Baz Castillo wrote:
> 2008/7/6 Paul Kyzivat <[EMAIL PROTECTED]>:
>
>> Instead, I think the caller should be providing the calling number as an
>> E.164 number, when it is in fact possible to represent it that way. This
>> will make it universally unambiguous, and meaningful the the maximum number
>> of possible receiving devices. The receiving device should then take
>> responsibility for rendering this the receiving user in a way that is
>> maximally useful and friendly for the receiving user.
>
> Hi, my first aim was this and this is what I did in outgoing calls to
> PSTN (I set P-Asserted-Identity as E164 complete number). But
> unfortunatelly it seems that common mobil phones and fixed phones
> render the entire number even if it's national/local, and people don't
> like it, the prefer to see 944990011 than +34944990011. :(
>
> Thanks a lot for your comment.
In the current world there has not been sufficient standardization. Or
perhaps I should say there hasn't been sufficient implementation of the
standards we have. Or maybe it is simply that the carriers have failed
to enable the implementations of the existing standards that are already
present in the equipment they have.
In any case, it is sad but true that when connecting to carriers you may
have to fix up the numbers to the form they can deal with. Or, if you
were a big enough fish, then they might do the fixing up of the numbers
you provide to the form they want.
There are really only two ways to do this:
- each domain has its own way of representing numbers.
whenever it connects to another domain it has to know
the (likely different) way that the other domain represents
numbers, and convert to that.
- each domain uses a common representation of numbers
(E.164) when talking to others. Whatever it uses internally,
it always converts to this standard form for talking to
others.
The former seems to be the norm, and it sucks. But it is consistent with
the carrier world view that peering relationships are all privately
negotiated on a 1:1 basis, and are a "big deal". It means that only a
small number of peers are feasible.
The latter makes it much more feasible to have open peering
relationships. Maybe that is why it isn't widely supported.
Within your domain, you can fix up however you wish. If there was wide
agreement on use of E.164, then it would be worthwhile for phones to
support it too. Then PBXs could be replaced with simply proxies. It is
not *hard* for the phone to convert to E.164 format. For any one locale
the configuration of the dial plan to do so is relatively trivial, and
not taxing on the phone to do. There just hasn't been any motivation to
do it.
Thanks,
Paul
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