TELECOM Digest Thu, 19 Jan 95 07:03:00 CST Volume 15 : Issue 46 Inside This Issue: Editor: Patrick A. Townson Re: Privately Owned Cables on Public Utility Poles (Greg Straughn) Re: What is a T1 Line? (Wally Ritchie) Re: Ancient Party Lines (Scott Falke) Re: New Area Codes Working From Toronto (Dave Leibold) Re: ISDN Over Wireless (John Lundgren) Re: Cattle Call (John Rice) International Freephone Numbers and European Phone Dials (J. Oppenheimer) Re: Looking For a CHILL Compiler (Per Bothner) Mobile Comms Questionnaire (Simon J. Wallace) NEC 2000IVS Wanted: Highend (Out-of-Band) Voice Mail Integration (Neubert) Missed Listing - and Lawyers, Not Lawnmowers (Carl Moore) A Call From Guess Where (David Farber via Stanton McCandlish) Always Busy 800 Number? (mre2b@virginia.edu) ISDN in Florida (Evon Bent) Voice File Formats (fonaudio@ix.netcom.com) Using U.S. Modem in Israel (Jeremie Kass) Can Caller ID Information Be Faked? (Chris Telesca) Telephone Vs. Cable TV as Data Carriers (y1n0@unb.ca) Looking for 900-MHz Cordless Hands Free Headset (Martin Soques) Areas Covered by Phone Book? (Benjamin P. Carter) TELECOM Digest is an electronic journal devoted mostly but not exclusively to telecommunications topics. It is circulated anywhere there is email, in addition to various telecom forums on a variety of public service systems and networks including Compuserve and America On Line. It is also gatewayed to Usenet where it appears as the moderated newsgroup 'comp.dcom.telecom'. Subscriptions are available to qualified organizations and individual readers. Write and tell us how you qualify: * telecom-request@eecs.nwu.edu * The Digest is edited, published and compilation-copyrighted by Patrick Townson of Skokie, Illinois USA. You can reach us by postal mail, fax or phone at: 9457-D Niles Center Road Skokie, IL USA 60076 Phone: 708-329-0571 Fax: 708-329-0572 ** Article submission address only: telecom@eecs.nwu.edu ** Our archives are located at lcs.mit.edu and are available by using anonymous ftp. The archives can also be accessed using our email information service. For a copy of a helpful file explaining how to use the information service, just ask. ********************************************************************** *** * TELECOM Digest is partially funded by a grant from the * * International Telecommunication Union (ITU) in Geneva, Switzerland * * under the aegis of its Telecom Information Exchange Services (TIES) * * project. 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Any organizations listed are for identification purposes only and messages should not be considered any official expression by the organization. ---------------------------------------------------------------------- From: gregs@best.com (g straughn) Subject: Re: Privately Owned Cables on Public Utility Poles Date: Wed, 18 Jan 1995 20:55:01 -0800 Organization: BEST Internet (415) 964-2378 In article , mfletch@ix.netcom.com (Mark Fletcher) wrote: > I have been told that we can apply to the local municipality for a > utility franchise, and then place our own cables on existing poles. At > our current cost of $18,000.00 annually for special circuits, this > possibility is very attractive to us. > If anyone has information about the process, or could point me to any > pertinant legal documents on the subject, I would be very greatful. I believe in California you can rent "attachments" to utility poles for something like $1.00 per pole per month -- perhaps your state utilities have a similar product requirement. Good luck, Greg Straughn ------------------------------ From: writchie@gate.net Subject: Re: What is a T1 Line? Date: 19 Jan 1995 05:46:16 GMT Reply-To: writchie@gate.net In , balcroan@netcom.com (Butch lcroan/ .nameBalcroan Lilli) writes: [pseudo technical babble deleted] > ... but there is more to consider here. The " MU LAW " is not a linear > scale it is more of a log function with more steps closer to the lower > levels where the ear is more senstive. I really can't believe 2 DB; > come on Jeff, 3 db is half power *and also the least amount the ear can > detect*. 1. The impact on SQR (Signal to Quantitzation Noise Power Ratio) of bit robbing is: 10 log (6/(6+3r)) where r is the number of robbed bits. This ranges from -1.76db for a single robbed bit to -6.02db if all 6 bits are robbed in the progress of the digital signal between the two end terminals. 2. The primary effect of uLaw is to extend the dynamic range of the channel. The SQR ratio for uLaw is not all that different from other forms of PCM, particularly for typical high speed modem modulations which have more or less uniform signal power. SQR's for PCM depend on the type of PCM and the properties of the signals. For Modem signals SQR's are on the order of 36db. However, THE EFFECT OF BIT ROBBING ON THE SQR IS INDEPENDANT OF THE SQR ITSELF. 3. Robbing (eliminating) the low order bit has the effect of doubling the average voltage quantization error which is the same as quadrupling the quantization noise power. Robbing the LSB of any PCM scheme will result in a 6db decrease in the SQR. If you only rob one bit in six, you quandruple the noise power only 1/6th of the time resulting in the equation above. 4. Jitter in digital transimission signals has nothing to do with the Signal to Noise Ratio of the PCM stream unless a frame slip results. Jitter at the codec would be of concern but in all equipment of reasonable design the frequency components of such jitter are very low and of no consequence to high speed modems (or speech). 5. The impact of bit robbing is not of alarming concern compared to the other types of noise and errors involved with high speed modems. By far, the worst transmission impairment involves continuous frame slips on digital facilities due to unsynchronized clocks. While these impairments cause only a minor (almost unnoticable) impact on voice, they are disastrous to high speed modems because they cause a phase shift that virtually guarantees an error and a loss of the absolute carrier phase required to demodulate the signal. The effects persist for many symbols until the transmitting carrier's phase can be reacquired. Wally Ritchie Ft. Lauderdale, Florida ------------------------------ Date: Wed, 18 Jan 95 21:40:07 -0800 From: scott@csustan.csustan.edu (Scott Falke) Subject: Re: Ancient Party Lines Organization: CSU Stanislaus In article scott@csustan.csustan.edu (Scott Falke) writes: > In re your story about party-line entertainment: > X-Telecom-Digest: Volume 15, Issue 11, Message 2 of 14 > [TELECOM Digest Editor's Note: The way you describe it was one way > of doing the ringing; there were various methods. What happened on > your system if you wanted to call someone on your party line? For 8-party, one dialed 119xy, where x was your line position (1-8) and y was the called party (1-8). The ring generator would alternate between the two. When the ring quit, you picked up the handset, cause they had too. If the ring didn't quit, you picked up the handset anyway. They weren't home. If you shared the same relative polarity with the called party (the gas tubes and tip/ting to gnd) you'd hear one long (i.e., yours) and two shorts (theirs) in repetition. THAT was real cool. Hey, a farming town, you know ... Scott Falke Turlock CA ------------------------------ Date: Thu, 19 Jan 1995 00:40:00 -0500 From: dleibold@gvc.com (Dave Leibold) Subject: Re: New Area Codes Working From Toronto Carl Moore wrote: > So you were able to get a Seattle number from 360 directory assistance. > Maybe 360-555-1212 is at least temporarily being routed identically to > 206-555-1212. Makes sense, considering 206 directory assistance centre would be set up for the areas under 360 ... just a matter of keeping the area codes straight. Bell Canada is able to route phone calls to various operators across a region for directory assistance purposes. In theory, an operator in Thunder Bay (807) could wind up fielding information inquiries for numbers in other Bell Canada area codes. ------------------------------ From: jlundgre@kn.PacBell.COM (John Lundgren) Subject: Re: ISDN Over Wireless Date: 18 Jan 1995 17:47:16 GMT Organization: Pacific Bell Knowledge Network Hersh Jeff (hershj@bah.com) wrote: > John Lundgren (jlundgre@kn.PacBell.COM) wrote: >> Find out if the phone company has a newer 5ESS switch. > To be fair to other companies, it should be noted that Northern > Telecom, Siemens, and other switch vendors also offer ISDN switches > that can act as central offices. Here in Pac Bell land, the only one that I've ever heard installed in the last few years have been 5ESS. I didn't know what other switches had the ISDN capability. Sorry if I gave the impression that the 5ESS was the only one that could do it, I didn't mean to. John Lundgren - Elec Tech - Info Tech Svcs Rancho Santiago Community College District 17th St. at Bristol \ Santa Ana, CA 92706 jlundgre@pop.rancho.cc.ca.us\jlundgre@kn.pacbell.com ------------------------------ From: rice@ttd.teradyne.com (John Rice) Subject: Re: Cattle Call Date: 18 Jan 95 22:33:49 CST Organization: Teradyne Inc., Telecommunications Division In article , RANDY@MPA15AB.mv- oc.Unisys.COM writes: > A local magazine (I think it was "Twin Cities Business") quoted an > item from an investment newsletter saying that some dairy farmers now > use pagers to call their cows. > One person here who's family raises cattle asked whether it wouldn't > be cheaper to keep a feeding a dog that herds the cattle instead of > paying monthly charges and air time. I can't feed my dog for $18/month, which is what I can get pager service (tone only) for, around here. One page a day is well under most limits for maximum pages/month. John Rice K9IJ rice@ttd.teradyne.com [TELECOM Digest Editor's Note: A couple of questions for whoever knows the answers ... is it hard to train a cow to respond to your call? Is there some sort of protective covering for the pager to keep it out of the rain and water, etc? A cow sees no problem with standing out in the field in the rain all day, or laying down on a muddy field to rest. In the heat of the summer a herd of cows in a pasture with a pond or lake will simply wander out into the pond and stand in water up to their neck to stay cool and keep the flies away. How does the pager withstand all this abuse? PAT] ------------------------------ From: Judith Oppenheimer Date: Wed, 18 Jan 1995 21:35:35 -0500 Subject: International Freephone Numbers and European Phone Dials European phone dials are being standardized and will include letters that correlate with the U.S. version. This took the ITU two years to decide, and is suppose to take effect next year. Judith J. Oppenheimer, Producer@Pipeline.com ------------------------------ From: Per Bothner Date: Wed, 18 Jan 95 20:21:51 -0800 Subject: Re: Looking For a CHILL Compiler > I am looking desperately for a CHILL precompiler or compiler running > under any UNIX, LINUX, OS/2 or DOS. A pre-release of the GNU Chill compiler is available by anonymous ftp at ftp.cygnus.com, directory pub, file chill-1.4.tar.gz. This is a dialect of Chill that Cygnus did for one customer. It is not complete Z200 (any version), but we have tried to follow the 1988 standard, with support for some features of the 1984 standard. The GNU debugger (gdb) already has (some) support for Chill. GNU Chill is structured similarly as GNU C and C++ (gcc and g++): I.e. a "back-end" that is language-independent, and a language-specific "front-end." Cygnus (that is me) and the Free Software Foundation are working on cleaning up and merging in Chill-specific parts of the back-end. One that is done, GNU Chill will be officially released by the FSF in conjunction with future gcc releases. If you want GNU Chill to implement some feature that it doesn't yet, you should contact me. Cygnus can do the work for a fee, or you can do it yourself (since it is free software). If your changes are clean and generally useful, I will merge them in (but you should talk with me before doing anything substantial). [Cygnus provides commercial support or negotiated (paid-for) enhancements to some GNU and other "free" software ("sourceware" as our marketing department calls it), including GNU Chill, C, and C++.] Per Bothner Cygnus Support bothner@cygnus.com ------------------------------ From: Simon J Wallace Subject: Mobile Comms Questionnaire Organization: Edinburgh University Date: Wed, 18 Jan 1995 11:32:58 GMT Hello there. I wonder if you could help me with a questionnaire I am doing for my Masters Degree. I would appreciate some opinions on DATA communications over mobile phones. It should only take a couple of minutes. Could you please post the replies to me at sjw@ee.ed.ac.uk. I shall post my findings as soon as I have collated them. Thanks in advance. Simon #:-) 1) Do you have a Digital (D), Analog (A) or Dual Mode (DM) phone ? 2) Do you at present use your mobile phone to transmit data ? 3) Do you at any time in the future plan to use a mobile phone to transmit data ? 4) If so what factors would influence your decision i) ease of use ii) cost of equipment iii) cost of calls iv) reliability v) Other please state : 5) What be your MAIN use of mobile data comms? Thanks again, Simon #8-) ------------------------------ From: dougneub@ix.netcom.com (Douglas Neubert) Subject: NEC 2000IVS Wanted: Highend (Out-of-Band) Voice Mail Integration Date: 18 Jan 1995 12:47:54 GMT Organization: Netcom If anyone has a line on a highend (like the one they demo the switch with at the shows) voice mail integration package for the NEC 2000IVS. Will you please E-mail me. I am currently using Reparte DOS ver. 6.5; their newest release (3 weeks old as of 01/18/95) setup up for the 1400 but the timing is way off and many calls get dropped if I am on úÿ my phone and you call me (on my extension) from the outside world. NEC boys have been o/s three day trying to fix/patch this up but are having no success. We installed an attendant card in the switch in the card last night so today we will see if this will be the fix. Please if any one has any suggestions good or bad let me know. Thanks, Doug Neubert Telsource Corp. Cleveland ------------------------------ Date: Wed, 18 Jan 95 17:43:02 EST From: Carl Moore Subject: Missed Listing - And Lawyers, Not Lawnmowers My latest Bell Atlantic phone bill in Maryland has a little insert which says: FOR YOUR CONVENIENCE ... (here, the reader turns the insert over) ... Keep these listings we missed in your new Bell Atlantic telephone book. Our goal is to give you an error-free phone book. We'll keep trying! -------------- That reminds me, some law office many years ago wound up in the Wilmington (Del.) yellow pages all right ... under lawnmowers. ------------------------------ From: mech@eff.org (Stanton McCandlish) Subject: A Call From Guess Where Date: 18 Jan 1995 17:39:40 -0600 Organization: UTexas Mail-to-News Gateway [Passed along FYI for a little tittilation for the readers. PAT] Date: Wed, 18 Jan 1995 11:48:37 -0500 From: farber@central.cis.upenn.edu (David Farber) Subject: a call from guess where I got a call from DC from someone in the inside I know well who said: 1. The LD carriers have hired Howard Maker to lobby for them on the "The planned Communications Act Re-write of the New(t) Congress"; 2. That there are meetings Thursday and Friday on the hill between staffers and industrial representatives -- not hearings; 3. The staffers have been told to make sure no plans, notes, etc. get to the public; 4. This is on the fast track. The person said that the "ravings" were aimed right and would remove many of the restrictions and controls on the carriers. As I said before -- stanger things have happened. Sounds like they may be happening again. And so much for a more open government! Dave ---------------- -- Stanton McCandlish
mech@eff.org

Electronic Frontier Foundation

Online Services Mgr. [TELECOM Digest Editor's Note: Do keep us posted. It sounds like some changes may be in store for us again. PAT] ------------------------------ From: Matt Subject: Always Busy 800 Number? Organization: University of Virginia Date: Thu, 19 Jan 1995 01:07:30 GMT What's an 800 number that is always busy? (and don't say Gateway 2000 Tech Support). Something that is guaranteed always busy. [TELECOM Digest Editor's Note: (Suspicious, squinting eyes) Why do you want to know? PAT] ------------------------------ From: xu@gate.net (Evon Bent) Subject: ISDN in Florida Date: Wed, 18 Jan 1995 14:19:41 GMT Organization: Cybergate Inc. Hey there, I was wondering if anyone has heard anything about Southern Bell implementing ISDN in Florida? I've been considering it to get a link to the net and a business line as well. I was also wondering if anyone could give me an idea of the rates I might get charged. If no one knows or isn't sure how about a number I might call to get this info? Barring that I was wondering if anyone was currently using ISDN in Florida and what their experiences with it were. TIA, Evon (xu@gate.net) ------------------------------ From: fonaudio@ix.netcom.com (TELEPHONETICS) Subject: Voice File Formats Date: 18 Jan 1995 19:56:11 GMT Organization: Netcom Can anyone give me information on the following formats for sound files: VBase, Dialogic, Rhetorex and New Voice Thanks. ------------------------------ From: kass@tacout.army.mil (Jeremie Kass) Subject: Using U.S. Modem in Israel Date: Wed, 18 Jan 95 16:00:09 EST I am interested in using the modem I use in the U.S. while I am in Israel. Is there any technical and/or legal problem in doing this? Also, what kind of telephone jacks are used there? This will be connected to a residential line, so will it be the same RJ-11 jack as here? Thanks, Jeremie Kass * IS/IT Consultant * JPK Computer Consulting Huntington Woods, Michigan, U.S.A. Internet : kass@tacout.army.mil * jkass@detroit.freenet.org jkass@cati.csufresno.edu * jkass@jpkcomp.detroit.mi.us jk914s2187@sycom.mi.org ------------------------------ From: sascjt@unx.sas.com (Chris Telesca) Subject: Can Caller ID Information Be Faked? Date: Wed, 18 Jan 1995 21:25:15 GMT Organization: SAS Institute Inc. I recently got Caller-ID and *69 Call Return service beause a friend and I have been getting prank and other strange phone calls over the last few months. Generally it works great, but several times I've seen a few numbers displayed numerous times and used *69 to call the number back, only to find that the people I've called back say they never called me at all (sometimes these are elderly people, BTW). So I was wondering if it possible to somehow fool Caller ID/Call Return features into displaying and/or calling back the wrong/incorrect number? Any ideas, thoughts, experiences? Thanks! Chris Telesca Associate Photographer (919)677-8001 x7489 SAS Institute Inc. / SAS Campus Dr. / Cary, NC 27513 / sascjt@unx.sas.com [TELECOM Digest Editor's Note: It cannot be spoofed where the transmission coming from the central office is concerned. What we have discussed here in the past is the possibility of the caller sending bogus information to the Caller-ID box *after* the phone is answered, but in the first second or so before the called party is likely to have examined the data very carefully. You answer, and the caller shoves some other stuff to your box at the instant the connection is made. Two things you might want to do: Look at the incoming information very carefully *before* answering; then as you answer the phone watch to see if it changes almost immediatly to something else. In that case, flip back through the entries -- if your display unit holds several entries, you probably can page forward or backward through them to check the time of the call, etc -- and look at the one received *just before* the one presently in the display window .. or maybe the second one before the present one. See if one of those matches what you recall seeing on the display before you answered. A second thing is try keeping a record of these calls by the number on display and the number before it in the memory, etc. See if there is any pattern or repetition. They may be feeding you false data, but if so you should (by backing up one or two entries) see the same old number on several occassions. Or, maybe they are not sending false data and in fact the number you see displayed is where the call came from. The person(s) who answer may deny making the calls, but if you see the same entries time and again then its almost assured *someone* in that household is making the calls, even if it isn't Grandma or Grandpa when they take your return call. Another possibility is the caller is putting his phone on forwarding to some unsuspecting person, then calling you from some other line via the forwarding link. He sets up call forwarding, dials your number and even while it is ringing tears down the forwarding link. In many places your Caller-ID box is going to show the number of the party who forwarded the call to you, even if they are unwitting accomplices to the whole thing. If you are using call return as provided by telco, then any spoofing of your individual Caller-ID box should be only coincidental since regardless of whatever data he funnelled over to you, the central office is not likely decieved. Use *69 rather than any local 'repeat dial' or 'dial number shown in window of ID unit' to return the call. If he is using illicit call forwarding to get through to you then you might try calling the number actually on your display, provided it is not bogus -- see above -- and *nicely* asking the people there if *they* happen to have Caller-ID also. If they do, maybe they would be so kind to look at their unit and tell you who the last caller was shown to them. If it is not someone they know, then chances are likely that is your person. PAT] ------------------------------ From: y1n0@unb.ca Subject: Telephone Vs. Cable TV as Data Carriers Date: Wed, 18 Jan 1995 18:11:09 GMT Organization: UNB CSD I am currently collecting information, in order to make a comparison between Telephone Companies vs. the cable TV companies as Data Carriers. I would appreciate it if anyone who knew of material pertaining to this subject and where the material would is availble, ie. a FTP site which may contain reports on similar subjects, could either post or e-mail their findings. It would be a great help! Thanks for you time! Jeff Y1N0@spitfire.unb.ca ------------------------------ Date: Wed, 18 Jan 95 16:13:27 CST From: Martin.Soques@amd.com (Martin Soques) Subject: Looking For 900-MHz Cordless Handsfree Headset Greetings! Subject line says all; I'm looking for a 900-MHz digital phone with a cordless headset rather than a cordless handset. That way, I don't have to crink my neck to hold a handset to have both hands free. A friend told me that he purchased one from a Sony Industrial catalog in his previous job. Any pointers to such a beast would be appreciated. Martin P. Soques martin.soques@amd.com Austin, Texas ------------------------------ From: bpc@netcom.com (Benjamin P. Carter) Subject: Areas Covered by Phone Book? Organization: NETCOM On-line Communication Services (408 261-4700 guest) Date: Thu, 19 Jan 1995 06:27:00 GMT A typical phone book with both white and yellow pages has a map with a large white area surrounding a smaller yellow area. What is this map trying to tell me? Are all the listed numbers in the white area supposed to be in white pages of the phone book? They don't seem to be. Is the phone book sent to all subscribers in the yellow area? If not, what does the yellow area stand for? It clearly has little or nothing to do with the locations of businesses that advertise in the yellow pages. The yellow areas of different phone books (ie, directories) fit together like pieces of a jigsaw puzzle. The GTE phone books where I live (near LA) show the parts of the puzzle covering their turf, but the PacBell phone books don't. Also, GTE has "neighborhood" directories that invade PacBell's turf. A "neighborhood" directory is typically much thinner than a real directory. Why? What is going on? I have a pile of phone books, and I seldom know which one to turn to for a particular purpose. Ben Carter internet address: bpc@netcom.com ------------------------------ End of TELECOM Digest V15 #46 *****************************