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Ringless voice mails from telemarketers

nytimes.com

21–30 of 227 posts

Re: Ringless voice mails from telemarketers

#21
post #15

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.

You really only need a double call. It's quite easy. I wrote this ages ago http://edoceo.com/exemplar/call-to-voicemail Oddly, my number gets blown up by these things.

How about call waiting?

Re: Ringless voice mails from telemarketers

#22

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…

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. I can tell you that's exactly what they are doing.

This is fascinating. It never occurred to me until now that there might be a window in the call process between "line is flagged as busy" and "phone rings."

I assume we're talking about a very narrow window here, right? How narrow?

Is it something that has always existed, or something that crept in because of the transition from phone-as-mechanical-device to phone-as-software?

Re: Ringless voice mails from telemarketers

#25

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…

How would this work when my phone declines their call? I assume it would hang up on the first call, then be available to hand up on the second call?

Because if not, I need to disable my voicemail.

Re: Ringless voice mails from telemarketers

#26

Earlier quoted context omitted.

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. I can tell you that's exactly what they are doing.

This is fascinating. It never occurred to me until now that there might be a window in the call process between "line is flagged as busy" and "phone rings." I assume we're talking about a very narrow window here, right? How narrow? Is it something that has always existed, or something that crept in because of the transition from phone-as-mechanical-device to phone-as-software?

Could be a second or two. The traditional phone systems are dog slow. Often takes 15 secs from A starts ringing to B does.

Re: Ringless voice mails from telemarketers

#28

Earlier quoted context omitted.

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. I can tell you that's exactly what they are doing.

This is fascinating. It never occurred to me until now that there might be a window in the call process between "line is flagged as busy" and "phone rings." I assume we're talking about a very narrow window here, right? How narrow? Is it something that has always existed, or something that crept in because of the transition from phone-as-mechanical-device to phone-as-software?

As long as it's a fairly consistently timed window (and I assume it is), it doesn't matter if it's just a few milliseconds.

On a related note, I'm still surprised to find that telephone operators haven't fixed the scenario "someone calls me and I just miss it, I call them back while they're trying to call me for the second time, and we both get a busy signal". As a naive outsider, seems like it wouldn't take much to just connect those two calls.

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