[Dundi] representation

[Bownes, Robert]

The problem with 800 numbers is that they are not unique. The same 800
number may be routed differently on a LATA or geographic basis. See
http://www.nanpa.com/nas/public/nonGeoNpasInServiceReport.do?method=disp
layNonGeoNpasInServiceReport for a list of the non geographic numbers.

But setting aside a space that is known to be reserved and unavailable
from the general PSTN for 'special services' such as PCS has some merit.

> > 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).