[asterisk-biz] ANI

[Jay R. Ashworth]

On Mon, May 12, 2008 at 11:56:06AM -0400, Peter Beckman wrote:
> On Fri, 9 May 2008, Steve Totaro wrote:
> > I think you are missing the whole point here. CID and ANI are DIFFERENT.
> >
> > A law concerning passing valid CID should not be passed.  I have used
> > it as a GUID between call centers.
> >
> > However, there should be a law against bogus ANI.
> 
>   So as a VoIP provider, what exactly is the ANI I should set?  A phone
>   number in the LATA in which my server is located?  Any phone number I
>   "own" or at least control?

If the subscriber for whom you're transiting the call to the PSTN has a
dialable DN for that line, then you should use that number.  If it's a
trunk-group type facility, any number which can be called to reach that
trunk group.  If the particular facility is outbound only, any number
that addresses an inbound facility billed to the same customer,
preferably at the same physical location.

If the facility is entirely outbound-only, then you should probably
find out where telcos get their assignments of non-dialable BTNs for
their own such facilities, and get some.

>   If a call is generated from my server as a direct result of another
>   incoming call, what do I set the ANI to?
> 
>      A) Any phone number I control
>      B) A single phone number I use for all outbound calls
>      C) Who cares
>      D) The phone number (if available) that was used to originate a call to
>         my servers/switches
>      E) Something else

If you're acting as a transit switch, then I would think you should
pass along the ANI appropriate to the originating station.  If you're a
smart conference bridge, or something like that, which generates
calls which are related, but not actually just an extension of the same
call, then some appropriate ANI assigned to the switch/adjunct itself.

>   The best reason for ANI spoofing with a different CLID is for billing.  If
>   I can set the ANI to any number, or even a number I own, in the LATA to
>   which I am terminating the call, I can get the lowest rates, while still
>   setting CLID to something meaningful to the terminating party.
> 
>   If we can exploit this, and it's not illegal, maybe it will cause the
>   incumbents to finally give up this inter/intralata pricing crap, get their
>   act together and make all our lives a bit more simple.

Possibly.  That doesn't mean that, from an engineering standpoint, I
have to approve, knowing something about the assumptions the PSTN makes
of a transported ANI.

>   This whole phone system is so messed up... here we all are, running VoIP
>   phone companies, and nobody seems to enforce, care, even know what the
>   proper setup is, and what the ANI should be, or that any VoIP termination
>   company on this list accepts or has rules on what the ANI can or cannot
>   be, much less that they bill on anything other than CLID.

Yup.  There are *lots* of people setting up machines and companies to
interact with the traditional PSTN who have never heard of AMA, or SS7,
or LSSGR (much less *read* all 14 volumes and 20,000-odd pages of
it)... and there's a *reason* why the major IXCs restrict direct access
to their SS7 routing control networks.

I fully expect there to be a shakeout; I'm a bit surprised it hasn't
happened already...

Cheers,
-- jra
-- 
Jay R. Ashworth                   Baylink                      jra at baylink.com
Designer                     The Things I Think                       RFC 2100
Ashworth & Associates     http://baylink.pitas.com                     '87 e24
St Petersburg FL USA      http://photo.imageinc.us             +1 727 647 1274

	     Those who cast the vote decide nothing.
	     Those who count the vote decide everything.
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