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Message Digest 
Volume 28 : Issue 126 : "text" Format

Messages in this Issue:
  Re: Telecom Digest archives questions [TELECOM]
  Re: Waveguide (was "size a major consideration...") 
  Re: Hackers Break Into Virginia Health Professions Database, Demand Ransom 
  Re: Telecom Digest archives questions [TELECOM]
  Re: Hackers Break Into Virginia Health Professions Database, Demand Ransom 


====== 27 years of TELECOM Digest -- Founded August 21, 1981 ====== Telecom and VOIP (Voice over Internet Protocol) Digest for the Internet. All contents here are copyrighted by Patrick Townson and the individual writers/correspondents. Articles may be used in other journals or newsgroups, provided the writer's name and the Digest are included in the fair use quote. By using -any name or email address- included herein for -any- reason other than responding to an article herein, you agree to pay a hundred dollars to the recipients of the email. =========================== Addresses herein are not to be added to any mailing list, nor to be sold or given away without explicit written consent. Chain letters, viruses, porn, spam, and miscellaneous junk are definitely unwelcome. We must fight spam for the same reason we fight crime: not because we are naive enough to believe that we will ever stamp it out, but because we do not want the kind of world that results when no one stands against crime. Geoffrey Welsh =========================== See the bottom of this issue for subscription and archive details and the name of our lawyer, and other stuff of interest. ---------------------------------------------------------------------- Date: Wed, 6 May 2009 21:58:25 -0700 (PDT) From: Thad Floryan <thad@thadlabs.com> To: redacted@invalid.telecom.csail.mit.edu Subject: Re: Telecom Digest archives questions [TELECOM] Message-ID: <e0bb5598-a23c-4032-a543-ad43dbba8fab@d25g2000prn.googlegroups.com> On May 6, 9:18 pm, tec...@tantivy.tantivy.net (Bob Vaughan) wrote: > [...] > I find mbox to be a very useful format. > > One of my major frustrations with Yahoo groups is the lack of any bulk > download capability, or any way of importing group archives into a > offline reader, other than saving individual posts. There is a widely available perl script that downloads en masse from Yahoo into mbox format. One caveat is one's Yahoo account can get "locked out" for awhile if too much is downloaded at one time. A Google search on "yahoo2mbox" will point you to the perl program and also many forums discussing how to get-around Yahoo's restrictions. ***** Moderator's Note ***** Before you go to the trouble, remember that the digest's archives are already available in mbox format, either from the web page, or from me if you need something more recent. Bill Horne Temporary Moderator ------------------------------ Date: Thu, 07 May 2009 11:31:14 -0500 From: Neal McLain <nmclain@annsgarden.com> To: redacted@invalid.telecom.csail.mit.edu Subject: Re: Waveguide (was "size a major consideration...") Message-ID: <4A030CD2.1010400@annsgarden.com> David Lesher <wb8foz@panix.com> wrote: > I've known of CATV companies that did use some coax backhauls to > the head end; now fiber rules the nest. CATV systems commonly used coax to backhaul signals from points within the distribution system (e.g., municipal buildings, schools, the CATV company's office) back to the headed for redistribution. But these signals were usually carried over the same coax network that carried downstream distribution signals. They were carried in the "subband" (5-20 MHz) below Channel 2. A hypothetical example: http://annsgarden.com/telecom/Backhaul.jpg In this example, a signal is carried upstream to the headend on a subband channel, and converted at the headend to Channel 13 for distribution to subscribers. Thousands of CATV systems also employed coax for "forwardhaul" to carry signals from the headend to the distribution network. Most of the early systems were built in mountainous areas where coax was needed to get signals from the headend on the mountain to the residents in the valley. In places with relatively flat topography, CATV companies built tall towers, often outside of town, and used coax to carry signals to the distribution network. Example: Hillsdale, Michigan: http://annsgarden.com/telecom/Hillsdale1.jpg http://annsgarden.com/telecom/Hillsdale2.jpg I wrote: > Nothing unique about that, of course: it's the same modulation scheme > that AT&T Long Lines had been using for years for their intercity > relays. Richard <rng@richbonnie.com> wrote: > No. To transmit the video of one TV signal, AT&T Long Lines used FM > modulation of one 20 MHz channel at 4 GHz or 11 GHz or one 29.xx MHz > channel at 6 GHz. The audio was transmitted separately on other > facilities using wide-band audio channels which were intermixed with > regular 4 KHz-wide analog voice circuits. The microwave systems had > names like TD, TH, TJ, and TL; the "T" meant televison because they > originaly were designed to capture the television transmission market. > The wider-band systems at 6 GHz were developed in the late 1950's in > case high-def TV for theaters was developed. > When not carrying television, these systems carried 1200 multiplexed > SSB voice channels (1860 channels for the 6 GHz system). Did "T" always indicate television? I thought TD could refer to a group of 1200 multiplexed SSB voice channels. http://long-lines.net/tech-equip/misc/EOBS84-363.html In any case, the comparison I was trying to make is that AT&T used SSB suppressed carrier modulation to combine voice signals into groups. I understand that AT&T used FM for the microwave link whether it was a TD group or one video signal. Frequencies within the CARS band can be used for FM or SSB AM. There are several frequency plans; the frequency plan I described in my previous post is Group C. Other Groups (A, B, and K) can be used for FM. The allocation plan, as defined in the FCC rules at 47 CFR 78, is at http://tinyurl.com/47CFR78 Many CATV companies used FM transmission in Groups A, B, and K to carry individual TV channels from remote points back to headends. Two examples: - Benton KY to Paducah KY. In this case, an FM CARS link was used to carry a Nashville TV station, received off-the-air in Benton, to the CATV system in Paducah. http://annsgarden.com/telecom/Paducah.jpg - North Bergen NJ to Lyndhurst NJ. In this case, an FM CARS link was used to carry a Philadelphia TV station, received off-the-air in North Bergen, to the CATV system in Lundhurst. Even though Lyndhurst is actually closer to Philadelphia than North Bergen, the difference in elevation between North Bergen (210 feet) and Lyndhurst (20 feet) made the link necessary. http://annsgarden.com/telecom/Lyndhurst.jpg The transmitter at North Bergen was located on the top floor of a multistory apartment building, inside an apartment that the CATV company rented. The equipment racks were in the living room, and the antennas were installed on the balcony. The whole thing came to an abrupt end in 1982 when a fire broke out in the apartment. It must have been a big fire: when I visited the site a few days later, everything in the apartment was black, the glass balcony doors were broken, and the aluminum antenna reflectors looked like Salvadore Dali's pocket watches. Neal McLain ***** Moderator's Note ***** I didn't do a lot of work on microwave, but I _was_ trained in "L" carrier. What little I remember was that one L carrier Mastergroup needed one coaxial cable, and that a single TV channel _also_ required a coaxial cable to itself. The coax had noticeable transit delays when used for TV, which were long enough that Huntley and Brinkley had to use a carefully-crafted set of "handoff" cues to compensate, so that one had to start talking a couple of seconds before the other one stopped: I don't know if Microwave eliminated the problem. I think TV signals that traveled on coax included multiplexed audio in later years, although I'm not familiar with the modulation scheme that was used. Bill Horne P.S. Please try to send "Plain Text" emails to the Digest, or the StripMime software will remove the HTML and "format" your submission in a way you may not care for. --- StripMime Report -- processed MIME parts --- multipart/alternative text/plain (text body -- kept) text/html --- Bill Horne Temporary Moderator ------------------------------ Date: Thu, 07 May 2009 17:39:03 +1000 From: David Clayton <dcstar@myrealbox.com> To: redacted@invalid.telecom.csail.mit.edu Subject: Re: Hackers Break Into Virginia Health Professions Database, Demand Ransom Message-ID: <pan.2009.05.07.07.39.02.823737@myrealbox.com> On Wed, 06 May 2009 07:34:08 -0400, Monty Solomon wrote: > Hackers Break Into Virginia Health Professions Database, Demand Ransom > > By Brian Krebs > > Washington Post > May 4, 2009 > > Hackers last week broke into a Virginia state Web site used by > pharmacists to track prescription drug abuse. They deleted records on > more than 8 million patients and replaced the site's homepage with a > ransom note demanding $10 million for the return of the records, > according to a posting on Wikileaks.org, an online clearinghouse for > leaked documents. Or the organisation merely restores the data from their daily backup for just the cost of time and inconvenience. At worst one day's changes may be lost - hardly worth $10M. -- Regards, David. David Clayton Melbourne, Victoria, Australia. Knowledge is a measure of how many answers you have, intelligence is a measure of how many questions you have. ***** Moderator's Note ***** The amount they demanded was just for bragging rights: it was crack by some script kiddie who didn't have much imagination, plus the usual "If it bleeds, it leads" fearmongering by the television stations. If he had had the brains to demand a more realistic amount - say, $3,000 - _then_ it would have gotten interesting. Bill Horne Temporary Moderator ------------------------------ Date: Thu, 7 May 2009 11:50:33 -0700 (PDT) From: hancock4@bbs.cpcn.com To: redacted@invalid.telecom.csail.mit.edu Subject: Re: Telecom Digest archives questions [TELECOM] Message-ID: <6f6382b0-ea70-423d-9279-9bc05753a030@b1g2000vbc.googlegroups.com> On May 6, 7:35 am, John Mayson <j...@mayson.us> wrote: Regarding the archives, I would like to say that having the Western Union Technical Review and other materials are a major asset. Those who built and maintain these archives deserve a big THANKS. > I remember when we had The Phone Company and would wait until 11 PM to > call our grandparents to save on toll charges.  Comparing 1981 to 2009 > is really stunning. As an aside, that 11 pm discount time was originally midnight; then they moved it to 11 pm. The 11 pm discount, was part of a new major long distance rate overhaul. IIRC, at that time introduced (1) a third large discount period (in addition to day and evening) and (2) one minute charging instead of the three minute minimum, and (3) applied to dial-direct calls only, operator handled calls cost more. This was introduced in the early 1970s that reflected virtually the whole country had DDD. (Those that didn't have DDD and those who had trouble placing a call and needed operator help still were charged DDD rates.) It is important to note this was a major rate reduction. Critics of the old Bell System who claim divesture and "competition" was necessary to reduce toll rates ignore measures like this. ------------------------------ Date: Thu, 07 May 2009 18:29:20 -0800 From: John David Galt <jdg@diogenes.sacramento.ca.us> To: redacted@invalid.telecom.csail.mit.edu Subject: Re: Hackers Break Into Virginia Health Professions Database, Demand Ransom Message-ID: <gu01s1$r44$1@blue.rahul.net> > Hackers last week broke into a Virginia state Web site used by > pharmacists to track prescription drug abuse. They deleted records on > more than 8 million patients and replaced the site's homepage with a > ransom note demanding $10 million for the return of the records, > according to a posting on Wikileaks.org, an online clearinghouse for > leaked documents. The state should simply pay the ransom, then have police on-scene when the money is delivered. There's no way the bad guy(s) can collect it without exposing themselves; that's why kidnapping for money no longer occurs in the US. ***** Moderator's Note ***** Maybe they planned on having it sent through PayPal ... If I were doing that kind of work, I would approach the organization that had been hacked, and offer a "No cure, no pay" contract to recover the data for some relatively minor amount. Assuming they were willing to sign, I'd produce a miracle cure, send them a bill, and make it my business to never, ever rub their nose in it. Bill Horne Temporary Moderator ------------------------------ TELECOM Digest is an electronic journal devoted mostly to telecom- munications topics. It is circulated anywhere there is email, in addition to Usenet, where it appears as the moderated newsgroup 'comp.dcom.telecom'. TELECOM Digest is a not-for-profit, mostly non-commercial educational service offered to the Internet by Patrick Townson. All the contents of the Digest are compilation-copyrighted. You may reprint articles in some other media on an occasional basis, but please attribute my work and that of the original author. The Telecom Digest is currently being moderated by Bill Horne while Pat Townson recovers from a stroke. Contact information: Bill Horne Telecom Digest 43 Deerfield Road Sharon MA 02067-2301 781-784-7287 bill at horne dot net Subscribe: telecom-request@telecom-digest.org?body=subscribe telecom Unsubscribe: telecom-request@telecom-digest.org?body=unsubscribe telecom This Digest is the oldest continuing e-journal about telecomm- unications on the Internet, having been founded in August, 1981 and published continuously since then. Our archives are available for your review/research. We believe we are the oldest e-zine/mailing list on the internet in any category! URL information: http://telecom-digest.org Copyright (C) 2008 TELECOM Digest. All rights reserved. Our attorney is Bill Levant, of Blue Bell, PA. ************************ --------------------------------------------------------------- Finally, the Digest is funded by gifts from generous readers such as yourself who provide funding in amounts deemed appropriate. Your help is important and appreciated. A suggested donation of fifty dollars per year per reader is considered appropriate. See our address above. Please make at least a single donation to cover the cost of processing your name to the mailing list. All opinions expressed herein are deemed to be those of the author. Any organizations listed are for identification purposes only and messages should not be considered any official expression by the organization. End of The Telecom digest (5 messages) ******************************

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