Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site whuxle.UUCP Path: utzoo!watmath!clyde!burl!mgnetp!ihnp4!whuxle!mag From: mag@whuxle.UUCP (Gray Mike) Newsgroups: net.consumers Subject: Re: Bothersome phone calls Message-ID: <522@whuxle.UUCP> Date: Fri, 13-Jul-84 16:55:12 EDT Article-I.D.: whuxle.522 Posted: Fri Jul 13 16:55:12 1984 Date-Received: Sat, 14-Jul-84 02:36:03 EDT References: <839@pyuxn.UUCP> <10262@lanl-a.UUCP> Organization: Bell Labs, Whippany Lines: 74 >Perhaps someone from AT&T and/or Bell can elaborate on the rationale for >a system where someone (or some *thing*) can call and tie up a person's >phone for as long a they like. I've heard of instances where a person >was called from a pay phone and then the caller just let the pay phone >hang by its cord, thus tying up the person's phone until they could get >the phone company to do something. > >It seems to me that this is a very bad feature (read: not just annoying >but potentially dangerous). Consider someone who lives in a very >isolated area where the phone may be the only recourse in an emergency. >Now suppose that such a machine calls, ties up the line and then breaks >(or for that matter a person calls, maliciously or otherwise). Now if >a life threatening event occurs and the person cannot use the phone, is >the phone company liable? > >Is there a good (or other) reason for this potentially dangerous arrangement? >Why can't (or isn't) the system set up so that the connection is dropped if >*either* end hangs up? I'm not an expert in switching, but I can give some information. Yes, it is a problem feature, and switches stopped being designed that way 30 or more years ago. On most Crossbar and all Bell electronic switches, the called party (i.e. you) will receive dial tone after 10 seconds on-hook. The calling party, however, will receive dial tone after about 1 second on hook. This feature is deliberate. It allows a called party to switch extensions without needing someone else to hang up the other phone. Sometimes you get 5 seconds to change, but usually it's 10. The calling party, on the other hand, is assumed to have already selected the extension they want to speak from, so they get dial tone immediately. This also allows them to make a rapid sequence of calls. On certain older switches, such as Panel and Step-by-step (vintage 1920s) the switches only look for call completion signaling from the *calling* end of the call, meaning that yes, indeed, someone (or something) can prevent release of your line. That was the state of the art at the time. When these switches were designed, there were no computers making unwanted calls. There were *very* few malicious calls. People still remembered to hang up the phone. So-called directly controlled switches(step and panel) still switch a bit less than 20% of Bell System lines. They are replaced with electronic switches as they wear out. Replacement is expensive. Modification to fix the problem is nearly as expensive as replacement. The money to run the phone companies comes from the ratepayers. When a phone company wants to make large, unusual capital expenditures, they must get approval from the *local* public utilities commission. I suggest that you complain to them about the problems of 1) unsolicited phone calls, and 2) switches that will not allow the called party to terminate a call in progress. I hope that this answers your questions. It may be that you are not allowing a full, *uninterrupted* 10 seconds on hook to cut off a computer calling you. If you keep on flashing the switchhook to see if it is still there, the switch will start timing the 10 seconds again. Michael Gray AT&T Bell Labs Whippany, N. J. P. S. I think it quite unlikely that emergency use and a hung phone will occur at the same time. Certainly much less likely than that the phone would be out of service due to say, lightning striking a distribution cable or a truck hitting it. It would be a better use of your time to worry about a 747 falling out of the sky and hitting you. :-) I sincerely doubt that a court would hold a phone company liable for such a situation, since they are *always* trying to upgrade switches and service (to improve revenue), and the PUCs just won't let them. Anyway, the problem will vanish (at least on Bell lines) in another 10 or 20 years.