[asterisk-biz] ANI

[Jay R. Ashworth]

On Fri, May 09, 2008 at 11:31:45AM -0700, Nitzan Kon wrote:
> I don't see a way to do it otherwise, as a carrier for outgoing
> traffic, how exactly are you going to check or verify that the
> CID being sent is not the ANI? just because you don't provide
> the incoming number doesn't mean it's not valid, and if you do
> it still doesn't mean it is. In essence as a carrier you have
> no choice but to "trust" the CID you're being fed.

Horse hockey.

As a carrier, interfacing to the PSTN, *you* are responsible for the
DNs that the subscriber is assigned, and neither I nor the FCC sees any
reason why you can't validate the numbers you're presented against that
list before extending calls into said PSTN.

> As far as regulating this - no thanks! I agree there should be
> a law out there against FRAUDULENT use, but the last thing any
> VoIP carrier needs is regulation on LEGIT use. In essence if
> you put a law out there saying "you should prevent your customers
> from abusing this" that's fine, but if you put out a law saying
> "spoofing CID is illegal" you're basically deeming most VSPs
> illegal. Again, just because I "own" the number from provider A
> doesn't mean I don't have to "spoof" it for provider B. Incoming
> and outgoing are totally separate.

Carriers should be (and TTBOMK, are) responsible for the DNs sent out
as (at least) ANI on lines they provide to subs, and they should not
permit them to be any number the client isn't assigned.  I'm less
concerned about CNID, for the reason you cite, though random Murricans
probably would not be.

There *is* no legitimate reason for spoofing ANI from the subscriber
level which does not break the semantics assumed of ANI.

Cheers,
-- jra
-- 
Jay R. Ashworth                   Baylink                      jra at baylink.com
Designer                     The Things I Think                       RFC 2100
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