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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: TTY phone fraud and abuse
In message <[email protected]>, Suresh Ramasubramanian writes: >[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. Yes. Depending on the countries and telcos involved, this is either illegal or "irregular" network access. Other schemes involve call-back (with the Internet as the signaling channel -- I first heard of that being used in 1994, when most people outside our business had never heard of the Internet) or calling through a third country if the difference in rates makes that profitable. --Steve Bellovin, http://www.research.att.com/~smb
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