phone fun, was GeoIP database issues and the real world consequences
johnl at iecc.com
Wed Apr 13 21:52:23 UTC 2016
>Is there the equivalent of BGP for number portability where every telco
>has the full table of who owns each prefix as well as individual routes
>for ported numbers ?
Not really. There's a switch database used for routing calls, but
that's different from LNP which is a layer sort of above that.
>Or is there a central database that is consulted before a dialed number
>starts to be connected so originating telco knows to send call ?
Often, if the switch can't tell that the number hasn't been ported.
>Or does the originating telco route the call to the original onwer of
>the prefix and lets that original owner figure out how to terminate the
That's called Onward Routing. They do it some places but not in North
America. See RFC 3482 for a well written overview of number portability.
>From a long distance billing point of view, if Bell Canada connects to a
>number originally onwed by AT&T but ported to Verizon, with whom would
>Bell share long distance revenues ?
They pay whatever long distance company they use, and that company
pays the owner of the switch to which it's delivered. The long
distance company also pays a very small amount to Telcordia which runs
the LNP database to tell whether the number's been ported and if so to
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