vances@egvideo.uucp (Vance Shipley) (07/11/89)
In article <telecom-v09i0227m01@vector.dallas.tx.us> lim@csvax.caltech.edu (Kian-Tat Lim) writes: > >The MCI spokesperson points out that this is *not* the same as lack of call >supervision, which caused "ring-no-answer" billing. > I believe that this sort of thing can happen because of transmission time for the supervisory signals. A user on one CO calls a distant CO; the supervisory signals to pass the destination and billing info are passed thru each switch along the path and then the end user terminal is rung. When the set is answered the CO sends the supervisory signals back to the originating CO along the same path they took to get there. Propagation delay is as much as 10 seconds I am told (this would not be typical). If the originator gave up before (real time) the destination answered the near CO would begin to send the necessary supervision signals toward the end CO. There is a window here where the path is reserved but no thru connection was ever achieved, this should not be billable. I should mention that with SS#7 (which MCI has in place) this should be changed for the better. Vance Shipley
ijk@cbnewsh.att.com (07/12/89)
One thing that many people might not be aware off is that what you hear ringing is NOT the end user's phone ringing [the user's phone might not be plugged in, and you'll still get a ring back.] Futhermore, the number of rings is not consistent with what you hear and what the user hears [sometimes, I've had people answer their phone before I even hear a ring - since I'm not a real believer in ESP, ...]. So, you might be counting the rings, and hang up on the third, while the answering machine has heard 4, and has started to answer. Ihor Kinal att!cbnewsh!ijk Standard disclaimer - although I work for Bell Labs, I'm a software person, and my real interfaces with phones are primarily the ones at home and sitting on the desk. My opinions are my own.
TK0GRM1%NIU.BITNET@uicvm.uic.edu (Gordon Meyer) (07/12/89)
In regards to MCI/AT&T charging for calls because the answering machine goes "clunk"....: Three years ago about ten 1 min. calls showed up on my MCI bill. I called customer service and was told that they happened because "the computer" thought the call had gone through. When I explained that I NEVER make one minute phone calls (doubt that many do...) They made the adjustment. I was told (no fooling) that the computer can get confused when it hears a noise on the line...it makes "the computer" think the call was connected. The rep suggested that (don't laugh) I may have coughed to the phone and confused the billing system. -=->G<-=-
dave@rutgers.edu (Dave Levenson) (07/13/89)
In article <telecom-v09i0229m01@vector.dallas.tx.us>, zygot!john@apple.com (John Higdon) writes: > In article <telecom-v09i0227m01@vector.dallas.tx.us>, lim@csvax.caltech.edu > (Kian-Tat Lim) writes: > > [From the LA Times "Consumer Views" column, by Don G. Campbell, 7/7/89. > > Paraphrased except for items in quotes.] > > QUESTION: J. T. observes several one-minute call charges on his/her MCI > > phone bill. These were made to answering machines that answer on the fifth > > ring; he/she always hung up after the third or fourth ring. > > ANSWER: [Complete and utter nonsense about clicks and machines making > > connections before ringing stops and such.] > When you place any call, local or long distance, upon connection of the > call you hear "ringback tone". This tone is supplied by the central > office at the called end and tells you that your call was successful > and that the party's phone is ringing (as opposed to not going through > or busy). > When the called party answers, ringback tone ceases immediately and the > connection "supervises", or in older parlance, "reverses". For the > majority of carriers that handle supervision, this is when the clock > starts. It makes no difference whether a machine answers or a person > answers, one thing is certain: ringback tone ending and supervision > beginning are a simultaneous event. If the machine answers on the fifth > ring, that's when billing begins and not before. There is an exception to this. If the called number is not a POTS (plain old telephone service) subscriber but an extension of a PBX (private branch exchange) that is reached by DID (direct inward dialing) trunks, then the audible ring signal is not generated by the far-end central office, but by the far-end PBX. Most PBX equipment acts like a central office in this case; it does not return answer supervision (start charging the caller) until the called end answers, and it stops the ring tone at the same time. Some PBX equipment also contains ACD (automatic call distribution) equipment. This usually answers immediately, and then plays a recording telling you that you are in a queue, until an agent is available. If no recording is provided, most ACD equipment will generate ring tones, even though the call has been answered. The AT&T System 85 PBX, when equipped with AUDIX (a voice-mail and call-coverage system that functions like a multi-user answering machine) will provide off-hook supervision at the time a call is sent to AUDIX for coverage (typically after three rings, if the station still hasn't answered). AUDIX will then generate ring tone until it is able to play the called party's personal greeting. This may mean that charging begins while ringing is still audible. -- Dave Levenson Voice: (201) 647 0900 Westmark, Inc. Internet: dave@westmark.uu.net Warren, NJ, USA UUCP: {uunet | rutgers | att}!westmark!dave [The Man in the Mooney] AT&T Mail: !westmark!dave
ab4@cunixb.cc.columbia.edu (Andrew Boardman) (07/13/89)
In article <telecom-v09i0232m09@vector.dallas.tx.us> Ihor writes: >One thing that many people might not be aware off is that what you hear >ringing is NOT the end user's phone ringing. [...] >Futhermore, the number of rings is not consistent with what you hear and >what the user hears. [...] This is, I believe, dependent on one's switch; at one point I lived on an old crossbar on which it was possible (through playing games with my loop resistance, etc.) to recieve a call while the switch was under the impression that the phone was still ringing. This is definitely *not* the case with my 5ESS box now; would someone who has specifics care to elaborate on them? Andrew Boardman, wrting from the phone-happy city of White Plains, NY. ab4@cunixc.columbia.edu ab4@cunixc.bitnet {backbone}!columbia!cunixc!ab4
davef@brspyr1.brs.com (Dave Fiske) (07/18/89)
In article <telecom-v09i0227m01@vector.dallas.tx.us>, lim@csvax.caltech.edu (Kian-Tat Lim) writes: > [From the LA Times "Consumer Views" column, by Don G. Campbell, 7/7/89. > Paraphrased except for items in quotes.] > > QUESTION: J. T. observes several one-minute call charges on his/her MCI phone > bill. These were made to answering machines that answer on the fifth ring; > he/she always hung up after the third or fourth ring. > > MCI first claims that J. T. would not have been charged if the machine hadn't > answered. An MCI manager later informs the customer that "when [you] call a Yet another twist on the "Did the call go through or not" dilemma: If a party has one of the following devices hooked up, the call is actually completed, but the caller is fooled into thinking that the number is still ringing. "...[T]he autoswitch answers the call on the first ring and listens for the 1100-Hz tone that is transmitted by an autodialing fax machine. If it senses the tone, the TF500 connects the incoming call to the fax machine. If it does not sense the tone, the device rings on through to the local telephone five times. If the phone is not answered the autoswitch automatically switches in the fax..." "Since the autoswitch actually answers the phone on the first ring and then takes a few seconds to decide whether the call is fax or phone, to prevent the caller from holding a 'dead line' while the device makes up its mind, the TF500 generates a phantom ringing signal back to the caller. As far as the caller is concerned, he hears the telephone ringing--he does not know that the call has actually been answered." from a review of the Command Communications TF500 Autoswitch, Radio-Electronics, November, 1988 -- "MAN USES TAPE TO STICK Dave Fiske (davef@brspyr1.BRS.COM) HIS TOE BACK ON!" Home: David_A_Fiske@cup.portal.com Headline from Weekly World News CIS: 75415,163 GEnie: davef [Moderator's Note: It was electrical tape he used, by the way, not scotch tape. In Wednesday's Digest, installers sometimes have a devil of a time finding unused pairs in the cable run, and not just on the 666 exchange either! And jsol expresses concern that when he gets some additional service the telco will skimp on pairs rather than run more. See ya tomorrow! PT]
r.a.a.@trout.nosc.mil (R.A. Anonymous, Jr.) (07/27/89)
You said in your message that, through playing with your line loop resistance,
that you could receive a call, while your switch was under the impression that
you had not answered.. This was a method used by Phone Phreaks in the early
80's to avoid billing. A phreak would put a 'colored' 'box' (they were
labeled by colors) on his/her line and receive calls from other phreaks at the
phone co's expense...
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Rodney Amadeus Anonymous, Jr. | pro-palace!r.a.a.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -epsilon@ames.arc.nasa.gov (07/30/89)
>You said in your message that, through playing with your line loop resistance, >that you could receive a call, while your switch was under the impression that >you had not answered.. This was a method used by Phone Phreaks in the early >80's to avoid billing. A phreak would put a 'colored' 'box' (they were >labeled by colors) on his/her line and receive calls from other phreaks at the >phone co's expense... 80's? Try 70s! Remember the stink when _Ramparts_ published details of how to build one of those? -=EPS=-
sandy47@ucsco.ucsc.edu (90784000) (07/31/89)
In article <telecom-v09i0258m07@vector.dallas.tx.us> pnet01!pro-sol!pro- newfrontier!pro-nfmail01!pro-harvest!pro-palace!r. writes: >You said in your message that, through playing with your line loop resistance, >that you could receive a call, while your switch was under the impression that >you had not answered.. This was a method used by Phone Phreaks in the early >80's to avoid billing. A phreak would put a 'colored' 'box' (they were >labeled by colors) on his/her line and receive calls from other phreaks at the >phone co's expense... > >- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Actually started in the late '60s. There was an article in Ramparts Magazine which gave actual details, including Radio Shack part numbers for building a "Yellow" box. Basically a resistor to be switched in at time of ring receipt to disable call charging (since the telephone had never been answered). "Blue" box details were worked out from the Bell Systems Technical Journal article published in the '60s which explained the inner workings of the new DTMF and MF systems. In the '70s "Captain Crunch" popularized this and added the computer twist. Go to your local US Government Depository Library (many public libraries and most university libraries fall into this category) and look up the Code of Federal Regulations for Telecommunications (several volumes). Part 68 has an interesting section on "Billing Protection" which deals with both the MF tones generated by "Blue" boxes and the impedance shifting done by "Yellow" boxes. But don't USE the information illegally or you'll be placed in a "Gray" box with steel bars :-).
ron@hardees.rutgers.edu (Ron Natalie) (08/06/89)
Then there's the green box. A device that sends a tone back to a pay phone releasing the deposited money, I believe. It's been a while since the Army Labcom security office has provided me 2600 newsletters to read. -Ron
tanner@ki4pv.uucp (Dr. T. Andrews) (08/09/89)
) ... green box ... tone to payphone
Do payphones not use out-of-band signalling? It would seem to invite
abuse if they used in-band signalling, especially if someone were
inclined to carry a recording of money being dropped into the thing.
--
...!bikini.cis.ufl.edu!ki4pv!tanner ...!bpa!cdin-1!ki4pv!tanner
or... {allegra attctc gatech!uflorida uunet!cdin-1}!ki4pv!tanneramb@cs.columbia.edu (Andrew Boardman) (08/10/89)
In article <telecom-v09i0286m08@vector.dallas.tx.us> tanner wrote: >) ... green box ... tone to payphone >Do payphones not use out-of-band signalling? It would seem to invite >abuse if they used in-band signalling, especially if someone were >inclined to carry a recording of money being dropped into the thing. They most certainly do use in-band signalling; in fact, such a recording was floating around department where I used to work. (For those that keep track of such things, a circuit hardwired to produce the tones necessary (coin deposit, not coin return) is referred to as a "red box". (Construction is trivial, but generally I prefer to pay for the service I get from AT&T. I dread the day that I read "Coin calls from this telephone are carried by the US Sprint PublicFON service.")) Andrew Boardman amb@cs.columbia.edu (but if you really have to, ab4@cunixc will work from bitnet)
john@apple.com (John Higdon) (08/11/89)
In article <telecom-v09i0286m08@vector.dallas.tx.us>, tanner@ki4pv.uucp (Dr. T. Andrews) writes: > ) ... green box ... tone to payphone > Do payphones not use out-of-band signalling? It would seem to invite > abuse if they used in-band signalling, especially if someone were > inclined to carry a recording of money being dropped into the thing. The insertion of money causes in-band signaling. It makes a little beep that is muted so that you don't hear it. One beep per five cents. This totals up on a display that the operator has in front of her (or on the automatic coin collection equipment.) It is a trivial matter to imitate these beeps with a device called a "red box". However, the first coin must be real, since the phone signals via DC loop that there is indeed at least one coin in the hopper (the first coin trips a flapper in the chute which is reset each time the hopper dumps to either the coin box or the return). If this signal is not present, they know you are pulling something. Pac*Bell has a few fraud prevention techniques to prevent this. One of them is to periodically and without warning dump the hopper into the coin box so that a new real coin will have to be inserted. Any dicrepancies and you better watch out. There are others which I'll keep to myself for now. -- John Higdon | P. O. Box 7648 | +1 408 723 1395 john@zygot.uucp | San Jose, CA 95150 | M o o !
eli@chipcom.com (08/11/89)
drea> Return-Path: spdcc!mailinglists.eecs.nwu.edu!telecomlist-request > From: Andrew Boardman <amb@cs.columbia.edu> > Subject: Re: While Phone Rings, Charges May Begin > > I dread the day that I read "Coin calls from this telephone are carried by > the US Sprint PublicFON service.")) Why do you dread Sprint more than any other long haul carrier? Don't all carriers have problems with starting charges if you let the phone ring or give a busy signal for a "very long time"? Which carriers are immune from such charges? If Sprint alone is screwing up billing because of "premature billing", this sounds like a good question for my pal at Sprint. I like to give him tough questions! [Moderator's Note: For one, AT&T has no problem with call supervision. They begin charging when the connection is actually established, and not after some pre-set period of time. You may occassionally listen to "The Larry King Show", a radio talk show late at night which is heard coast to coast. The announcer always gives a phone number to call if you want to talk on the air with Larry King, and his announcement is phrased thus, "...if we have a free line, you will get a ringing signal....let the phone *continue to ring* until it is your turn to speak with Larry....we will answer you a few seconds before you go on the air..." . Typically, you listen to ringing for 10-15 *minutes* -- sometimes half an hour -- while the callers ahead of you voice their opinions. Try that on a Sprint line sometime. Chances are your Sprint rep friend will tell you they do not have 'call supervision equipment' and cannot tell when the call actually starts. PT]
cowan@marob.masa.com (John Cowan) (08/12/89)
In article <telecom-v09i0286m08@vector.dallas.tx.us> tanner@ki4pv.uucp (Dr. T. Andrews) writes: >Do payphones not use out-of-band signalling? It would seem to invite >abuse if they used in-band signalling, especially if someone were >inclined to carry a recording of money being dropped into the thing. What you describe is called a "red box", and generates three different tones: 5 cents (ding), 10 cents (ding ding), and 25 cents (blonng). More modern payphones perhaps use out-of-band signaling, but long ago and far away, a recording of those noises would serve quite well in deceiving the operator. Details suppressed to protect the guilty. -- Internet/Smail: cowan@marob.masa.com Dumb: uunet!hombre!marob!cowan Fidonet: JOHN COWAN of 1:107/711 Magpie: JOHN COWAN, (212) 420-0527 Charles li reis, nostre emperesdre magnes Set anz toz pleins at estet in Espagne.
davef@brspyr1.brs.com (Dave Fiske) (08/12/89)
In article <telecom-v09i0289m06@vector.dallas.tx.us>, zygot!john@apple.com (John Higdon) writes: > In article <telecom-v09i0286m08@vector.dallas.tx.us>, tanner@ki4pv.uucp > (Dr. T. Andrews) writes: > > ) ... green box ... tone to payphone > > Do payphones not use out-of-band signalling? It would seem to invite > > The insertion of money causes in-band signaling. It makes a little beep > that is muted so that you don't hear it. One beep per five cents. This > totals up on a display that the operator has in front of her (or on the > automatic coin collection equipment.) It is a trivial matter to imitate Not that long ago, operators had to be able to distinguish the beeps for various coins. Presumably, if you could throw nickels and dimes into the slot fast enough, the operator would lose track, and you could get your call put through for less than the correct toll. -- "ANGRY WOMEN BEAT UP SHOE SALESMAN Dave Fiske (davef@brspyr1.BRS.COM) WHO POSED AS GYNECOLOGIST" Home: David_A_Fiske@cup.portal.com Headline from Weekly World News CIS: 75415,163 GEnie: davef