A Whitelist for Phone Calls?

javacowboy asks: "I've been getting lots of strange phone calls lately. Most of the time, my phone would ring less than three times and then stop before I can answer. Then, a couple of nights ago, I got a call at 3am in the morning. It had stopped ringing by the time I woke up. *69 revealed a number with an area code of 632, which does not exist. I called the number, and the call would not complete past the area code. I want a product or service with which I can set up a -whitelist- of numbers that I allow to make my phone ring. Any number not on the list, or an unlisted phone number, tries to call me, and the phone doesn't ring at all. I would pay as much for this service as I would pay to have my number removed from the phone directory. Is something like this possible? If so, how would I do it?"

I'm getting fed up with: wrong numbers; callers hang up on me as soon as I speak into the phone; telemarketers; crank calls; late night calls; people I know that I no longer wish to speak to; etc. My telco charges $8 a month for call display, which is exorbitant. Still, a call display won't prevent my phone from ringing. A do not call list will not prevent my phone from ringing. Getting my phone number removed from the phone directory will not prevent wrong numbers. How can filter out the calls that I don't want to deal with?"

Looks like Manila to me

[Marxist Hacker 42]

Looks like your mysterious 632 area code is really Manila [howardforums.com], probably an outsourced call center in the Philipines.

Your topic is a Dupe [slashdot.org], but a simple google search turned up these guys [sentinelco...ations.com].

Asterisk / Broadvoice?

[karnal]

I have two solutions:

1. If you're a geek, try to wrap your head around Asterisk - I'd have to think either it would have that functionality built in, and if not - wouldn't be too hard to tell it to pass whitelisted #s, but dump everything else to voicemail....

2. I use Broadvoice at home, and when I don't want to be disturbed, I *77 the phone. *78 unblocks it (takes it out of Do Not Disturb) - of course, this doesn't help when it's late at night and I don't do the *77 ahead of time, but I can make sure I don't get awoken again.

Both of these implementations almost require an internet connection. While you can purchase FXO modules for Asterisk, I've just not had the interest in making a go at it with a PSTN connection....

Another alternative - only one phone in our whole house rings. I sleep rather well, so I probably wouldn't hear it if it rang at night...

Use Asterisk

[ResQuad]

The scripting for the extensions.conf file is more than powerful enough to have a CallerID based whitelist, heck, you can even have it database powered. You can have the Asterisk PBX do what ever you want. How about:
Step 1: Phone call comes in, Asterisk picks up
Step 2: If the CallerID is whitelisted, ring internal phone.
Step 3: If the CallerID is blank/unknown, prompt for CallerID or send to voicemail.
Step 4: If the CallerID is black listed - do whatever you want (perma-onhold, disconnect, fast busy, etc)

Its not hard, really. It would only take a few minutes to setup once you have asterisk running.

Grand Central

[EMeta]

The NYT had a very interesting article about Grandcentral.com, which I believe would whitelist and much more, if you sign up for them, which at the time, I believe was free. Here's the article. [nytimes.com]

Re:Asterisk / Broadvoice?

[Southpaw018]

Asterisk will handle this easily, but will only work if all phone in question are tied directly into it. For example, a cell phone won't be included in the solution. Just a note, since the submitter doesn't specify.

telezapper

[phatvw]

I think you're talking about the Telezapper [telezapper.com] A quick google search turned up a nice privacy page with useful, although fairly obvious recommendations: http://www.privacyrights.org/fs/fs3-hrs2.htm [privacyrights.org]

Super Simple

[TubeSteak]

I'm not sure how this made it to the front page.

The easiest solution:
Go down to your local big box store & check out the various cordless phones. You'll find the ones with fancier base stations will allow you to deal with incoming calls however you like.

After the person has called. You just setup that # not to ring, to go directly to voicemail or if the phone supports it, it'll just hang up.

You don't even have to give up your corded phones & buy extra handsets.

"Privacy Manager"

[oneiros27]

From the article you linked to, the very last item mentioned is 'Privacy Manager'. My brother had it (or something remarkably similar ... he said it was from the phone company, not a device) for a few years, before he just went and got his number un-listed.

The only time he ever had a problem was when he was waiting for a call from our step-father, who it seems had problems with his cell phone, and was trying to call from a pay phone, and kept getting blocked ... but he wasn't presented with the prompt to enter the code. (and of course, we were supposed to be picking him up from the airport, and he had changed flights, so it caused a bit of a problem).

And I know the incident happened more than 5 years ago, so it's been available for some time. (as I remember being slowed down at the security gate for carrying 3 knives, 2 cell phones and a PDA, but as I wasn't arrested, it must've been before Sept 2001)

Re:Quick Answer

[Akaihiryuu]

On my cell phone, I set custom rings for everyone in my address book. I can turn off the default ring on my phone by setting it to "alarm only". Anyone in my address book will still ring, anything else is silent. I just use this setting when I don't want to be disturbed. The only time I answer an unrecognized phone number is when I'm expecting to possibly get calls, for example right now when I'm looking for a job in another state. If it really is important, and I don't answer it because it's an unrecognize number, well that's what my voice mail is for. If it's really important, they'll leave a message and I'll call them back. I haven't had a telemarketing call in many years. In fact, I haven't even had to use my "alarm only" setting...only time I tried it was to test it.

GrandCentral.com

[biohack]

I am using a web-based service that, among other features, helps to control which calls will ring my phone(s): GrandCentral [grandcentral.com]. It allows to define several groups of white-listed numbers with separate response behavior (ring, send to voicemail, etc.) and also includes a couple of different screening options. For dealing with known telemarketers they even offer to play a "number not in service" message, but most auto-dialers can't get past the call screening anyway. It's a free service while in beta, but they promise to keep basic features free indefinitely, including "unlimited inbound minutes, unlimited voicemail (up to 30 days old), and access to all of our core features". This NYT write-up [nytimes.com] describes a few of the options in more detail.

Re:Asterisk / Broadvoice?

[darnok]

> 1. If you're a geek, try to wrap your head around Asterisk - I'd have to think either it would have that
> functionality built in, and if not - wouldn't be too hard to tell it to pass whitelisted #s, but dump everything
> else to voicemail....

Absolutely - I'm putting in an Asterisk box progressively over the last few nights to do all this and more. The rules aren't absolutely fixed in my head yet, but will be something like:
- voicemail for everyone in the house; if someone calls, they can choose who they leave a message for
- no calls after 10pm, unless it's from a whitelisted number (i.e. parents, friends)
- no calls between 7pm-8:30pm, unless it's from a whitelisted number
- *all* calls from numbers without caller ID go direct to voicemail (i.e. phone doesn't even ring), regardless of when the call comes in

Asterisk basically gives you full-on routing capability for your incoming and outgoing calls. You can define rules based on caller ID, time of day, ... - pretty much any "property" of either incoming or outgoing calls.

Re:telezapper

[stephanruby]

Someone mod the parent down before too many slashdotters waste their money, the telezapper used to work -- but now it doesn't anymore. A few years back the automatic dialers relied on the standard telephone tones to know that a telephone had been disconnected, or busy, or whatever. The telezapper exploited that functionality by faking those tones whenever someone called. And the telezapper got so popular, that the makers of the automatic dialers stopped relying on those tones alone to know that a phone was disconnected, so now the telezapper is completely useless. Not only that, but the telezapper was also rarely used once purchased since *everyone* not just the telemarketers -- got to hear the annoying tone at the beginning of the call. Now, the people selling telezappers are just rip off artists, they know their products don't work -- so don't expect a refund.

No, the real solution is to get caller id from your phone company (assuming you live in a State or a Country that allows it) and buy one of those devices that white lists the phone numbers you want to receive, and otherwise allows your callers to punch in a special code in case they're not white listed yet. That special code, you could give it out only to your friends, or you could simply leave it on your outgoing message -- since even leaving it as an outgoing message will probably screen out a good portion of automated telemarketers. And notice, I said buy a device, don't rent, do not lease it from your phone company, those things are dead cheap, and the phone company is just going to make a nice profit on the monthly fee.

And someone said it already, but I just want to repeat it in case some of you missed it. If you have a cell phone, check your manual to see what kind of built-in functionality it already has. Even the basic cell phones these days have some pretty decent scheduling functionality, ring tones or vibrations for different numbers (or categories of numbers), and automated forwarding of certain phone calls directly into voice mail.

Re:Asterisk / Broadvoice?

[Anonymous Coward]

I did this with asterisk earlier this year. When a call comes in, the number is checked against a mysql database to see if the number is whitelisted or blacklisted. Whitelisted calls go straight through, and blacklisted calls hear a message that their number is blacklisted and then asterisk hangs up. Greylisted calls go to a message that says telemarketer calls are not allowed, then proceeds to give the user the option of ringing through or leaving a message. Calls between 10pm and 9am get an 'after hours' message which will go to voicemail unless the user enters the 'emergency' code which will then ring through. Works like a charm, and we've not been bothered by unwanted calls since.