[69447] in North American Network Operators' Group
Re: TTY phone fraud and abuse
daemon@ATHENA.MIT.EDU (Suresh Ramasubramanian)
Sun Apr 11 21:59:05 2004
Date: Mon, 12 Apr 2004 07:18:51 +0530
From: Suresh Ramasubramanian <suresh@outblaze.com>
To: "Steven M. Bellovin" <smb@research.att.com>
Cc: Sean Donelan <sean@donelan.com>,
Scott Call <scall@devolution.com>, nanog@merit.edu
In-Reply-To: <20040411231937.A59607B44@berkshire.research.att.com>
Errors-To: owner-nanog-outgoing@merit.edu
[4/12/2004 4:49 AM] Steven M. Bellovin :
> Naturally, miscreants (to use robt's terminology) try to find ways to
> make such calls from the U.S. more cheaply. Sometimes, this involves
> hacking PBXs, other times, it involves subscription fraud, or a variety
> of other kinds of misbehavior. The responses are similar to those we
> use on the Internet -- traffic analysis (similar to looking at
> NetFlow), blacklisting calls to certain countries from, say, pay
> phones, etc.
There is another class of people who route calls out from the USA to
India (or elsewhere) using VOIP, terminate the calls at an unauthorized
(that is, not run by a licensed telco) exchange in india, and then route
the calls out through the local pstn or mobile network.
Quite a few of the "call $asian_country for cheap" phone cards you find
at ethnic grocery stores seem to work on these lines.
The local telco doesn't see a red cent of any settlement charges when
this happens. Local telcos are, of course, all against this, and use
any and every excuse to get these exchanges busted - a procedure that
typically involves having the local police raid the exchange.
srs
--
srs (postmaster|suresh)@outblaze.com // gpg : EDEDEFB9
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