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TrapCall Service To Bypass Caller ID Blocking
cemaco writes in with news that TelTech, developers of the infamous SpoofCard service, have come out with something even more controversial: a set of services for revealing blocked caller ID numbers. The services take advantage of a loophole in the way caller ID blocking works — it has never been effective when calling an 800 number, because the recipient is paying for the call. So TelTech instructs you how to forward blocked calls (transparently) to their 800 number; the call comes back to your phone in seconds with the formerly hidden caller ID revealed. Advocacy groups for victims of domestic violence are concerned. Victims of annoying calls hiding behind caller ID blocking are rejoicing.
We're concerned because most crisis call lines are not the phone bank you see on TV, but volunteers that work at home. As a crisis line volunteer, you want your home number blocked so that the client calls the crisis line and not you.
Some of the people we deal with aren't particularly stable and may try to latch on to the crisis worker - these, if they go into common use, could cause mental health issues for the users of crisis hotlines, AND the volunteers.
I can't believe the ignorance of the referenced article. See http://en.wikipedia.org/wiki/Automatic_number_identification for an intelligent explanation of what's happening. The important part is...
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Because ANI is unrelated to caller ID, the caller's telephone number and line type
are captured by ANI equipment even if caller ID blocking is activated. The destination
telephone company switching office can relay the originating telephone number to ANI
delivery services subscribers. Toll-free Inward WATS number subscribers and large
companies normally have access to ANI information, either instantly via installed
equipment, or from a monthly billing statement. Residential subscribers can obtain
access to ANI information through third party companies that charge for the service.
>>>
To summarize...
* There are 2 *TOTALLY UNRELATED* means of getting *THE NUMBER THAT IS CALLING YOU*
* Caller ID (technically CNID) sends the callers number during the ringing signal.
Any outfit with their own PBX can send out whatever crap they want as CNID.
That's how spoofing services work, and how telemarketers can fake CNID
* ANI (Automatic Number Identification) is billing information data. Spoofing that
effectively constitutes fraud. And you can be certain that phone companies will
do whatever is necessary to make sure their billing systems work . ANI is very
difficult to spoof.
Having said that, TrapCall can be beaten. Not spoofed, but beaten. ANI passes the number making the call. If you call via Skype, your call is forwarded to Skype, who then forwards the call to the destination. The destination gets Skype's billing data. This is technically correct, but useless for identifying the originator. Oh yeah, Skype pays connection charges at the receiving end, so don't expect them to freely work for 1-900 numbers. This is roughly equivalant to calling from New York to Los Angeles to ask your brother to pass on a message to someone in Atlanta. The person in Atlanta knows they got called by somebody from Los Angeles. This is technically correct, but doesn't let them know that the message originated from New York.
I'm not repeating myself
I'm an X window user; I'm an ex-Windows user
RTFA. It's court-mandated, they don't have a choice.