TELECOM Digest Thu, 2 Jun 94 11:05:00 CDT Volume 14 : Issue 266 Inside This Issue: Editor: Patrick A. Townson Re: Help: Bad Phone Lines in San Jose (John R. Haggis) Re: Help Needed: Fax/Answering Machine/Phone (Steve Cogorno) Re: Security of a Code? (Mark Brukhartz) Re: Ground-start trunk line sharing product? (Dave Ptasnik) Re: S-s-s-stuttering Dial Tone Detection (Dave Ptasnik) Re: U.S. Postal Service and the Information Highway (Dave O'Shea) Re: Out-Going Call Blocking to Local Numbers (thssamj@iitmax.iit.edu) Re: Average Data Speed of Wire Telegraphy (Wes Leatherock) Re: Average Data Speed of Wire Telegraphy (Dick St.Peters) Re: Cost of Caller ID in PA (Fred Linton) Re: Cost of Caller ID in PA (Robert G. Schaffrath) 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 GEnie. It is also gatewayed to Usenet where it appears as the moderated newsgroup 'comp.dcom.telecom'. Subscriptions are available at no charge 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. 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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: haggis@netcom.com (John R. Haggis) Subject: Re: Help: Bad Phone Lines in San Jose Organization: Millennium Research Date: Wed, 1 Jun 1994 12:21:03 GMT In article terry@hh.sbay.org (Terry Greenlee) writes: > I am having trouble with my phone lines at home and I was wondering if > anyone else had this same thing happen to them? Terry, I've had bad phone lines all over the place, including the rusty, musty lines up in Boulder creek. > Monday a Bell tech will come out to test. Yeah, and he'll say, "We don't guarantee lines for more than 4800 baud. You have to get a leased line to do better." This is their mantra. Don't accept it for a second. > Does anyone at Pacific Bell know how to fix these problems? No. That's the problem. Short of replacing all the lines, everywhere. Maybe we should get phone service over the cable TV lines ... Seriously, here's how you deal with them. To the "not rated over 4800 baud" mantra, just insist that everybody else has better operation, and keep insisting that it's your individual lines. Keep insisting that they change drops or incoming trunk lines until it works. Tell them it worked before for you at another house (it has for me, both the strategy and the mechanics). Above all, keep calling and going over peoples' heads. The people at Pac Bell, while regular, nice people on the outside, become flaming assholes when at work under the strain of a job they have no concept or understanding of. Give 'em h*ll. John (haggis@netcom.com) ------------------------------ From: cogorno@netcom.com (Steve Cogorno) Subject: Re: Help Needed: Fax/Answering Machine/Phone Date: Wed, 1 Jun 1994 11:14:56 PDT Said by: Kathy Vincent > 2. Can anyone recommend integrated equipment -- a three-in-one > combination in which all THREE elements are quality? > She says she's found some combinations, but the answering > machine is usually junk. She would prefer a digital answering > machine (i.e., no tapes). Can anyone recommend anything that might > do the job -- especially anything <=$500? Does she have a computer? I have a modem that is made by Promethus Products, called the Ultima Home Office. It integrates 14,400 bps DATA, 14,400 Send/Receive Fax, and Voice mail with up to 100 mailboxes. It will only handle one line, and it has a few quirks, but once you get the hang of it, it works wonderfully. There are PC and Macintosh versions availible for around $390. One caveat: for voice mail, the computer must be on, and running the MaxFax software (it can be in the background; the modem will automatically bring it to the front). If she has a Macintosh with Solid-State power (All of the Macintosh II series, Quadra 700, 800, 840, 900) there is an adated availible for about $30 that will turn on the computer on the first detected ring. For other models, you can get a similar adapter, but more expensive (around $150) which is like a power strip: you plug the computer into it, and it turns the power on after the first ring. Steve cogorno@netcom.com ------------------------------ Date: Wed, 1 Jun 94 14:12:25 -0500 From: mark_brukhartz@il.us.swissbank.com (Mark Brukhartz) Subject: Re: Security of a Code? The basic measure of cipher strength is key length. If a cipher has no other weaknesses (a major point), it can still be broken by trying every key until one produces recognizable data. This is known as a "brute force attack." Each bit of key length doubles the time needed for a brute force attack. Assume that an attacker has a million CPUs, each capable of trying a thousand keys per second. (I believe that those are reasonable figures for a well financed opponent attacking a typical cipher.) Here are the average times to break a cipher by brute force for several key lengths: 40 bits 9 minutes 48 bits 40 hours 56 bits 1 year 64 bits 300 years 72 bits 7 thousand years 80 bits 20 million years These times will shrink as computers get faster. For data which must remain secure for several decades, extraordinarily long keys are warranted. Ciphers based upon typical pseudo-random number generators are weak, and can be broken quickly by a professional cryptographer regardless of key length. Such ciphers are all too common, often built in to applications such as word processors and spreadsheets. Academic cryptographers publish new ciphers which have passed analysis by their immediate colleagues. Many of these ciphers, if not most of them, are still broken within a few years. Beware of proprietary ciphers, because they have not been subjected to such scrutiny. For moderate data security, the old US Data Encryption Standard (DES) is still a decent algorithm. In over fifteen years of academic analysis, no serious weakness has been revealed. Unfortunately, its 56 bit key is small by today's standards. It is widely speculated that government spy bureaus have built specialized DES cracking hardware which can complete a brute force attack within minutes. DES still provides excellent security from ordinary hackers and nosy employees, though. Mark Brukhartz mdb@il.us.swissbank.com ------------------------------ From: davep@u.washington.edu (Dave Ptasnik) Subject: Re: Ground-Start Trunk Line Sharing Product? Date: 1 Jun 1994 19:16:42 GMT Organization: University of Washington Rod Regier writes: > Background: > My organization is currently using a Mitel SX-100 PBX. The incoming > TELCO trunk lines are ground-start trunks. I have no "free" locals > I would like to use the two-line pool at night to add to my dialup > modem pool without adding any additional (expensive, $C1000/yr) telco > lines. > If the two-line pool used normal loop lines, I could use a product > like the Cardinal Communications Comshare 550 to support both incoming > voice and data calls, as well as outgoing PBX calls. One of the Mitel family of SMar-T dialers includes a loop/ground start converter. Placet this on the line and you can use any 2500 equivalent on a ground start trunk. Ask you Mitel dealer for details. A 4 line unit probably costs less than $300. Dave Ptasnik davep@u.washington.edu ------------------------------ From: davep@u.washington.edu (Dave Ptasnik) Subject: Re: S-s-s-stuttering Dial Tone Detection Date: 1 Jun 1994 19:26:00 GMT Organization: University of Washington kmp@tiac.net (K. M. Peterson) writes: > My problem: I don't want to have to lift the handset to find out if I > have messages. Has someone come up with a box to sit on one's line > and detect this (and flash a lamp or something)? A Canadian company called Xinex Networks, Inc. makes an amazing telephone called the mindSET. It periodically samples the line looking for stutter dial tone, and turns on a big message light when it finds it. There is a nice display that shows Caller-ID information. It also has a whole bunch of speed dial keys and function keys, or you can enter in bunches of names and scroll through them on the display, like a Rolodex. Naturally it has a speakerphone. It also passes through the ring provided by the phone company, so if you have custom ringing, you can hear the different patterns. All in all a very nice unit. Don't know the price, just got to play with a demo unit for a while. Dave Ptasnik davep@u.washington.edu ------------------------------ From: dos@spam.wdns.wiltel.com (Dave O'Shea) Subject: Re: U.S. Postal Service and the Information Highway Date: 1 Jun 1994 20:04:27 GMT Organization: WilTel Reply-To: dave_oshea@wiltel.com > [TELECOM Digest Editor's Note: Despite what Runyan may say, the United > States Postal Service is in very bad condition. Over the past three months > there have been major upheavals in the USPS here in Chicago, as Runyan > himself can attest. Several top officials of the post office here have There is value in the post office, though: Much like New York City's subways, where "I took the subway" is excuse for any lateness at all, "it's in the mail" is a wonderful, irrefutable excuse for whatever kind of misbehavior you feel like. If I forget to send my car loan payment in, I just say "the check's in the mail" when they call. End of case, I have two weeks to do whatever I want. Now, If I was dumb enough to use someone like Fedex, the bank could simply ask for an airbill number, and in 30 seconds, I'd be hanging my head in shame, admitting that I blew the car payment on a new 500mb drive. (Sarcasm intended. I drop by the post office weekly to give them the mail that has been delivered to me, though it is addressed to people sometimes near, sometimes far. And exchanging mis-delivered mail is a great way to meet the neighbors.) Dave O'Shea dave_oshea@wiltel.com Sr. Network Support Engineer 201.236.3730 WilTel Data NelzNitwork Services [TELECOM Digest Editor's Note: I do the same thing at my post office box downtown. Whenever I go in, I'll find several items in my Box 1570, Chicago, IL 60690 (intended for me) with a rubber stamp endorsement on the front of the envelope saying 'opened in error by First National Bank of Chicago'. As well, there will be a few items in my box not for me, but either for a nearby box or as often as not, someone who lives at 1570 (some street) or Apartment 1570 (at some address), Chicago 60609, or Buffalo Grove, IL 60090. I used to simply take them to the call counter and leave them with the clerk, but sometimes the very same letter would be in my box *again the next day*. Now I have a little rubber stamp which reads "Not For Box 1570 at Chicago 60690" and I stamp that on the envelope before giving it back. If I still get the same letter back a couple times more (it has happened) then I take a pen and completely obliterate the zip code the writer put on the envelope forcing the 'nixies clerk' to seek it out manually. One little kid sent a postcard to WGN-TV at their box, which is 10003 (note the extra zero in the middle), Chicago, IL 60610. He wanted his free prize offered on some television show for little folks. I got that damn postcard *three times* recycled to my box. Finally I penciled in a note on the front by the address saying 'Try Fort Dearborn Station at 606-one-oh'. When it arrived a fourth time (yes!) at my box the next day with my 'try Fort Dearborn' notation scratched out I took the card with me and dropped it off with the receptionist at the front desk at WGN's offices, 2301 W. Bradley Place on my way home. But the best one of all was printed in {Pravda} several years ago. It seems some Soviet school children had been given the assignment of writing letters to the leaders of different countries asking them about their country and encouraging them to work for peace among nations. One little guy named Ivan had written to President Reagan. The picture in {Pravda} showed this kid about ten years old with a very bewildered look on his face and an envelope in front of him addressed to "President Reagan, United States of America". On the envelope, a rubber stamp endorsement quite plain for everyone to read, "Moved, left no forwarding address, return to sender" with indicia of the Washington, DC post office. (He was president at the time.) The newspaper's caption to the picture read, "Postal Service says cannot locate President". The picture and accompanying story was on the employees bulletin board at 60690 for several months. It was taken down finally when it had accumulated quite a bit of graffiti written on it, no doubt by disgruntled postal workers and/or customers who saw it. PAT] ------------------------------ From: thssamj@iitmax.iit.edu (jani) Subject: Re: Out-Going Call Blocking to Local Numbers Organization: Illinois Institute of Technology, Chicago Date: Wed, 1 Jun 94 20:08:28 GMT In article thssamj@iitmax.iit.edu (jani) writes: > Is it possible to block outgoing calls to selected local numbers? > Ameritech says they do not have such a service. Only kind of outgoing > call blocking they offer is to 1-900 numbers and total blocking to > long distance service. > They suggested I should check out if there was such a device available > from a third party. Is there such a thing? > I would prefer if the phone company could do it at their end as it > would be more secure. (The device can not be unplugged and disabled.) > [TELECOM Digest Editor's Note: Telco does have classes of service which > allow total blocking to local calls; blocking of long distance calls [deleted...] > and can be secreted in an out-of-the-way place on your premises. A > detirmined person could get into them, but they do the job in most > cases. PAT] The phone company, Ameritech in Illinois says they do not offer the class of service that blocks all local calls as they are in the business of getting people to make more calls -- not restrict calls. Are they saying this because it is not technically possible or is it because they have marketing considerations in mind? Is it possible to change to a phone company that offers such a service. The line is located in a apartment building. Is there another local phone company in the area (Chicago) that would offer such a service? amj [TELECOM Digest Editor's Note: There is, for all intents and purposes, no alternative to Illinois Bell (Ameritech) in your case. Your volume of business does not warrant it. If your phone bill was like that of University of Chicago, or City of Chicago, or Amoco, or Rush-Presbyterian and around five hundred thousand dollars per *month* and you had a service representative at telco assigned exclusively to your account, who worked on nothing but 'amj' business eight hours a day like the above accounts, then telco would be coming around asking you what you wanted. *Yes*, they do offer a class of service which restricts all local calls and only allows long distance. And when you called and asked about it, the rep who dealt with you probably wrote you off as a crackpot and let it go at that. They won't give it to you, so forget it. For quite a few years I had a part time job reconciling the phone bill and making service changes for a large company downtown with centrex. A phone on my desk was for long distance only. If I dialed seven digits to anywhere it went to intercept (call cannot be completed as dialed). It did accept 1+ ten digits; it did not accept 0+ dialing. I think the bill there was only about sixty thousand dollars per month, making it one of the smaller 'larger' accounts. If you want to do business with the 'competition' at Teleport (or whoever it is that moved in on Ameritech's territory), plan to show them where you can give them at least several thousand dollars per month in business. They do not handle residence stuff. You are not in Central Telephone's territory (I assume you are not in the little sliver of land they control on the northwest side) so you cannot go to them unless you want foreign exchange service and believe me you, when you see the bill for FX you'll wish you had stayed with IBT and a few unauthorized local calls from time to time. Do as you were told here yesterday and visit the local Radio Shack store in your neighborhood. Be creative and find a way to secrete the device on your premises, under lock and key if necessary. You will get along just fine. PAT] ------------------------------ From: wes.leatherock@oubbs.telecom.uoknor.edu Date: Wed, 01 Jun 94 08:50:22 Organization: [ OU BBS University Of Oklahoma (405)325-6128 TBBS ] Subject: Re: Average Data Speed of Wire Telegraphy Wanted Quoting itstevec@rocky.ucdavis.edu (Steve Chafe) > Does anyone know what the average speed (in characters per minute, > or whatever is appropriate) of a professional telegrapher would > have been when wire telegraphy was the main mode of electronic > communication? I'm trying to do a comparison of data communication > speed then and now, so I'd love to hear any thoughts that people > can offer. I can't give a numeric figure, but I can provide some anecdotal information. In the 1950s, I was a reporter and editor for United Press in Dallas. Our circuits serving clients (newspapers and radio stations, primarily) were 60-speed Teletype circuits fed by ASR machines (punched tape run through a distributor so that full throughput could be obtained, unlike hand keying which is not more than two-thirds as fast effectively, and often much less.) On Saturday afternoons during the football season, many of the accounts of football games came in on Western Union short period leased circuits. (At that time, Western Union had exclusive contracts with virtually all stadiums, including college stadiums.) We would have several such games coming in over Western Union circuits, most of them set up on teletypewriters which were apparently hand cranked at the stadium end by Western Union operators drawn from their regular pool. However, occasionally we had the pleasure of seeing a real live operator show up with his key and sounder. This was always a pleasure. The stories that came in by Western Union teletypewriter were always slow and frequently had errors that had to be questioned. (Press copy uses full text, full punctuation, etc., and a story about a football game is naturally full of figures and statistics, all of which seem to be foreign to what Western Union operators usually handled.) But the Morse operator with his key was something different. (Some used bugs, some straight keys.) And obviously his counterpart at the game was similarly competent. You could start a story moving on the wire as soon as the Morse operator gave you a couple of paragraphs. He would stay ahead of the 60-speed Teletype circuit without any difficulty. If there was a question, he would break the sending operator and get the matter straightened out immediately, even if the operator at the game had to ask the writer. (Often, if there was something questionable, the receiving operator had already noticed and asked the sending operator.) They were real professionals and it was always a pleasure to deal with them. And their real output was a whole lot faster than the hand cranked teletypewriter copy of the other circuits, and much more accurate. Of course, these were operators with real press experience and used the Phillips code, understood what the press requirements were, and I think got real pleasure out of exercising their skills, and incidentally drawing our admiration. A few years before, I had been writing play-by-play (newspapers used that in early editions in the 1940s) for University of Oklahoma games, and I had a Western Union operator sitting beside me, sending each paragraph as I wrote it. He, too, was similarly good and not infrequently caught me in mistakes (in a friendly, helpful manner, too). Press operators were, I think probably the elite of operators sending in the wire telegraph days. Perhaps those working for brokerage wire houses could also put in a claim to this, but I'm not sufficiently familiar with them to be able to judge. Wes Leatherock wes@obelisk.pillar.com wes.leatherock@oubbs.telecom.uoknor.edu ------------------------------ From: stpeters@dawn.crd.ge.com (Dick St.Peters) Subject: Re: Average Data Speed of Wire Telegraphy Reply-To: stpeters@dawn.crd.ge.com Organization: GE Corporate R&D, Schenectady, NY Date: Wed, 1 Jun 1994 22:54:12 GMT What a bunch of old memories this question brings up! 30 years ago I used to run very high speed machine-keyed transmissions for people to practice listening to, out of W1MX, the MIT student ham radio station. W1AW, the ARRL station, used to tranmit practice transmissions at speeds up to 35 wpm. We started there and ran up to 65 wpm. How fast someone can copy depends a LOT on the nature of what is being sent. Simple text that makes sense is an awful lot easier than the random letters and numbers taken from the tables of vacuum tube characteristics that were sent for a latter portion of the transmission at each speed. Nobody can copy that at the higher speeds, because of the way people hear code. At very low speeds, you hear individual dits and dahs. Somewhere around 5 wpm there's a barrier where you can't go higher until you learn to hear whole letters. Get past that barrier, and you can run up to 20+ wpm pretty quickly, where there's another barrier where you have to start hearing whole syllables, even whole words. Once through that, you can again progress rapidly (with practice) up to 60 wpm or so, where you max out. At these speeds, code essentially has become another language. If the transmission has a spelling error, you "hear" the error as a sort of dissonance ... you still get the meaning, but it doesn't sound right in the same way a basic grammar error doesn't sound right in language. That changed way of perceiving code at ca. 20+ wpm makes it very hard to transcribe code at higher speeds. Up to the character-at-a-time barrier, you can learn to type the characters as they come in with a kind of brain bypass ... code character to finger keystroke. Once you hear whole words, you can no longer do this. Also, someone who can hear the 60 wpm language with no sweat can have a problem copying very slow transmission. Ah well, 'twas a looong time ago. Dick St.Peters, Gatekeeper, Pearly Gateway; currently at: GE Corporate R&D, Schenectady, NY stpeters@dawn.crd.ge.com ------------------------------ From: flinton@wesleyan.edu Subject: Re: Cost of Caller ID in PA Date: Wed, 1 Jun 1994 20:41:25 GMT Organization: Wesleyan University In article gvaeth@netcom.com (Greg Vaeth at Jerrold Communications) writes: > Caller ID in Pennsylvania ... for residential customers is > $6.50/month, business is $8.50. How does this rate compare to other > states? Caller ID for SNET residential customers in Connecticut is also $6.50/mo., where available. Calls to New Haven (203 776 xxxx) often get reported as "out of area" or, more bluntly, "error", or even just " ------ " whenever the routing utilizes a non-caller-ID-aware switch (even on calls known independently to originate in the same 776 exchange (!)). So a "perfect privacy filter" Caller ID is certainly not. But, at $0.20 per day, it's good cheap fun, anyway, to see whether SNET got it right this time, or muffed it yet again. Fred [E.J. Linton : FLinton@eagle.Wesleyan.EDU : fejlinton@mcimail.com] ------------------------------ From: gfimda!rgs@uunet.UU.NET (Robert G. Schaffrath) Subject: Re: Cost of Caller ID in PA Date: Thu, 2 Jun 1994 01:09:40 GMT Organization: Kraft General Foods > An insert in my latest bill contained a notice that Bell Atlantic will > offer Caller ID in Pennsylvania in August. The cost for residential > customers is $6.50/month, business is $8.50. Call blocking and > anonymous call rejection are free. This charge seem outrageous > considering that the equipment to do it is already there, right? How > else does return call, repeat call and all that stuff work. How does > this rate compare to other states? New York Telephone, uh NYNEX, also charges $6.50. It's a rip off but I really wanted the technology. I got even though. I was carrying custom calling feature (forwarding and call waiting) which totalled more than the $6.50. I dropped them so my bill actually went down! Robert G. Schaffrath, N2JTX Internet: rgs%wpmax2%gfimda@uunet.uu.net Systems Engineer CompuServe: 76330,1057 Maxwell House Coffee Company Phone: 914-335-2777 Kraft General Foods Corp. Slogan: "ervice is ur mott" ------------------------------ End of TELECOM Digest V14 #266 ******************************