[Dundi] representation

[Mark Spencer]

> Examples of non-unique numbers in the US include the 700 and 800 area
> codes:
> * 800 numbers are regional (by state/province and country) and
> * 700 numbers are carrier specific.
> They are e.164 numbers.
> (subject to correction by someone that actually has the spec in front of
> them.)
>
> A few approaches come to mind for non-unique numbers:
> * Don't list them at all,
> * provide multiple answers and let the client sort it out,
> * pick a region/carrier to support, (e.g. michigan/iaxtel)

800 numbers are essentially unique as far as I know, when prefixed by the 
appropriate country code (e.g. "1" in the US/Canada).

700 numbers are another issue.  The DUNDi/e164 trust group is essentially 
piggybacking on the existing infrastructure of the E.164 number allocation 
to avoid having an additional central authority for handling numbers.  It 
would seem to me incompatible with the spirit of the group to represent 
numbers such as 700 which are carrier specific, as opposed to having 
official meaning as part of the global numbering plan.  This also would 
seem to open the door to more danger (e.g. what if sip phone wants to 
represent their 747 area code within DUNDi/e164 which is clearly not 
allocated to them, and in fact has been assigned for use to relieve the 
818 area code, see 
http://www.areacode-info.com/headline/1999/ca991108.htm).

Mark