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Ringless voice mails from telemarketers

nytimes.com

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Re: Ringless voice mails from telemarketers

#4

Post by extrapickles »

The article doesn't describe how the technology works.

Due to the slow speed (100 voicemail/min) its likely what they are doing is initiating a call far enough for the phone system to busy out your phone, then very quickly placing a second call that the phone system sends straight to voicemail as your phone is busy. Once this call starts to hit voicemail, the original call is dropped.

I doubt phone companies let people directly send voicemail to people as they wouldn't be billing for that.

Re: Ringless voice mails from telemarketers

#5

Post by 13of40 »

Overtonwindow wrote: post #2

But HOW does it work? It's not clear by the article precisely how this is done. Possibly a triple call system. Three calls to that same number at once, each a millisecond after the other, and when the third hits the voicemail the other two disconnect immediately.

Wasn't thinking of that. I assumed the phone company was complicit and selling this as a service to the telemarketers, but we can't really know if the article avoids any implementation details.

Re: Ringless voice mails from telemarketers

#6

Post by mee_too »

Overtonwindow wrote: post #2

But HOW does it work? It's not clear by the article precisely how this is done. Possibly a triple call system. Three calls to that same number at once, each a millisecond after the other, and when the third hits the voicemail the other two disconnect immediately.

Or bribe the phone company and get direct access to the mail box.

Re: Ringless voice mails from telemarketers

#7

Post by matt_wulfeck »

In early 2000s this used to be a feature of my phone and I actually liked it. It allowed me to call someone and leave some information quick and easily. Text messages have largely replaced the need for that now. So much so that I've often pondered disabling my voicemail altogether.

Re: Ringless voice mails from telemarketers

#8

Post by eli »

extrapickles wrote: post #4

The article doesn't describe how the technology works. Due to the slow speed (100 voicemail/min) its likely what they are doing is initiating a call far enough for the phone system to busy out your phone, then very quickly placing a second call that the phone system sends straight to voicemail as your phone is busy. Once this call starts to hit voicemail, the original call is dropped. I doubt phone companies let peop…

If I call my T-Mobile voicemail I can leave a message on someone else's T-Mobile line. Definitely possible.

Re: Ringless voice mails from telemarketers

#9

Post by bifel »

The method (at least here in my country) is really simple (and not really a secret): The voicemail can be reached from a special number. This number is easy to derive from the actual phone number (usually inserting one or two digits, depending on the provider). When the "owner" calls the mailbox, he gets the "admin" functionality. Anyone else calling it can only add messages. The rest is just simple call forwarding. So all that is needed is finding out the number of the mail box.
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