Path: utzoo!mnetor!tmsoft!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!uwm.edu!bionet!ames!ucsd!casbah.acns.nwu.edu!nucsrl!telecom-request From: !carroll@ssc-vax.uucp (Jeff Carroll) Newsgroups: comp.dcom.telecom Subject: Re: Should Projects be Connected to the Phone Line? Message-ID: Date: 17 Feb 91 00:43:18 GMT Sender: news@casbah.acns.nwu.edu Reply-To: Jeff Carroll Organization: Boeing Aerospace & Electronics Lines: 70 Approved: Telecom@eecs.nwu.edu X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@eecs.nwu.edu X-Telecom-Digest: Volume 11, Issue 124, Message 1 of 8 In article <74667@bu.edu.bu.edu> atn@cory.berkeley.edu (Alan Nishioka) writes: > However, in response to my article, John Higdon brought up a problem > that had been bothering me. He said that my project SHOULD comply > with the various parts of the FCC rules since it needed to connect > directly to the phone network. He's right, legally speaking. The FCC is pretty specific about what you can connect to the PSTN, for a good reason - because in our deregulated telecom environment, they're the only ones who can be. > Now, many books and magazines regularly publish projects that connect > to the phone line. Even the usually respectable TELECOM Digest > recently published several such projects. I don't think any of them > have been certified anything by anyone. Most if not all of them are illegal. The more savvy publishers and kit-sellers (e.g., Radio Shack) will *tell* you not to connect these things to the PSTN - that they are just fine to connect to your in-house intercom, but shouldn't be connected to your phone wires. > I see two issues involved: One of safety (to craftspersons, etc. ) and > the other of just following the rules. I can see if I were going to > sell these devices that I would be interested in both, but as a > hobbyist I am mostly interested in the first. There's a third issue - protecting the integrity of the network. As a telephone subscriber, you consume an amount of network resources. In order to keep the cost of billing within the troposphere, telco doesn't go to the trouble of measuring many of the resources you use such as seconds of dial tone, number of unsuccessful calls, local office battery power consumed, etc. This does not mean that you are granted a license to use these resources wantonly, carelessly, or in such a way as to impair the quality of service delivered to other subscribers, or to make it unreasonably costly for telco to provide you service. In a circuit-switched network, it is pretty hard for one subscriber to impair another's service, unless it's by calling that subscriber repeatedly and continuously. (Assuming that everyone has private lines.) In other kinds of network, it's a lot easier; witness what broadcast storms or sendmail worms can do to a LAN or an Internet. In Europe (particularly in the Netherlands), the PTT has serious problems with pirate broadcasters setting up shop on the cable TV network. Now, I'm not trying to tell you that you can't attach your well-designed, well-built project to the PSTN; I'm just trying to explain to you why telco is justified in cutting you off or seeking legal remedies when your non-certified device causes chaos in the central office. > I understand there are network interface devices that one can buy and > thus have any device automatically safe and certified to connect to a > line, but these are out of my budget. I also don't see how they make > that much of a difference. They make a difference because they (at least to the engineers at the FCC) prevent you from degrading the network. Note to flamers: I'm not suggesting that telco has the Public Interest primarily or even significantly at heart. Nor am I suggesting that Judge Greene knows anything about technology. Nor am I suggesting that just because the FCC says something makes it so. I'm just pointing out that system engineering is what it is, and in order for a system to work, one needs to respect the designers' intentions. Jeff Carroll carroll@ssc-vax.boeing.com