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Message Digest 
Volume 29 : Issue 44 : "text" Format

Messages in this Issue:
 Re: ISDN (was: Re: Two 1A ESS COs to be Replaced in 2010; 59 Remain)
 Re: HDSL, was ISDN (was: Re: Two 1A ESS COs to be Replaced in 2010; 59 Remain)
 Re: ISDN (was: Re: Two 1A ESS COs to be Replaced in 2010; 59 Remain)
 Re: Do you know where there are Teletype machines for sale?
 Re: ISDN (was: Re: Two 1A ESS COs to be Replaced in 2010; 59 Remain)
 Re: ISDN (was: Re: Two 1A ESS COs to be Replaced in 2010; 59 Remain)
 Re: How do you get your number off a list so that it's gone, gone


====== 28 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: 12 Feb 2010 06:37:20 -0000 From: John Levine <johnl@iecc.com> To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org. Subject: Re: ISDN (was: Re: Two 1A ESS COs to be Replaced in 2010; 59 Remain ) Message-ID: <20100212063720.34999.qmail@simone.iecc.com> > I ordered a PRI for one client who wanted the Nortel BCM system (a > PBX), and also PRIs for clients who wanted the asterisk VoIP > system. Amazingly (to me) all PRIs were actually fiber lines to the > MPOE where they were converted to <something> (2-pair) over Cat5 > that connected to the PCI card(s) in the asterisk system(s). I don't think anyone's still installing traditional two-pair T1. My T1 was two-pair when they installed it in 1995, but a couple of years ago they switched to HDLC, so there was one pair coming to the house, and a little line powered box that turned it back into the traditional two pairs I plugged into my CSU/DSU. There's tons of used T1 equipment available, on ebay and specialized places. I got a WANIC T1 card on ebay for under $100, probably because nobody else knew what it was. R's, John ***** Moderator's Note ***** Please tell us how "HDLC" is used in this context, and which physical-layer protocol is used: the highest-speed two wire data line I'm familiar with is IDSL, but that tops out around 144 kbps. Bill Horne Moderator P.S. Why is it that everyone else has the best toys? ;-)
Date: 12 Feb 2010 16:42:49 -0000 From: John Levine <johnl@iecc.com> To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org. Subject: Re: HDSL, was ISDN (was: Re: Two 1A ESS COs to be Replaced in 2010; 59 Remain ) Message-ID: <20100212164249.84020.qmail@simone.iecc.com> >I don't think anyone's still installing traditional two-pair T1. My >T1 was two-pair when they installed it in 1995, but a couple of years >ago they switched to HDLC, so there was one pair coming to the house, Sorry, too many TLAs today. That's HDSL, a flavor of DSL that is symmetric in both directions and is intended to replace T1s. It runs on one pair, can go 12Kft between repeaters, and is less sensitive to funky cable. I just droped by the local telco who tells me their low end business fiber product is 5mb down/512kb up for $69/mo which is not that much more than the so-so DSL I have now. R's, John
Date: Fri, 12 Feb 2010 17:57:58 +0000 (UTC) From: David Lesher <wb8foz@panix.com> To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org. Subject: Re: ISDN (was: Re: Two 1A ESS COs to be Replaced in 2010; 59 Remain ) Message-ID: <hl44r6$riv$1@reader2.panix.com> John Levine <johnl@iecc.com> writes: > I don't think anyone's still installing traditional two-pair T1. My > T1 was two-pair when they installed it in 1995, but a couple of > years ago they switched to HDLC, so there was one pair coming to the > house, and a little line powered box that turned it back into the > traditional two pairs I plugged into my CSU/DSU. >***** Moderator's Note ***** > Please tell us how "HDLC" is used in this context, and which > physical-layer protocol is used: the highest-speed two wire data > line I'm familiar with is IDSL, but that tops out around 144 kbps. The LEC {be it I or C} sells you a DS1 circuit at your location. They deliver it over 2 pairs from their SmartJack [tm, I'm sure] on your wall. How they get it to you is THEIR call. It could be circa 1961 [yes.. JFK, mini-skirts, etc] T-1, two pairs, repeater in the middle of each 6Kf segment [amazingly, right where the "paint can" loading coils were already, hmmm.] of cable, etc. OR they could use other means. Maybe there's fiber in your basement already. [If you're in a skyscraper....] Or a SLC-FO next door. Or they use single pair HDSL, and a different color module in the SmartJack. I was told by an installer that is was an Engineering option. T-1 needs two pairs, stomps over ADSL sharing the same bundle, and such; but it can used repeaters to get a LONG way, up to {ISTM} 150 miles before the jitter gets out of hand. [Such must use alternte power arrangemnets..] The HDSL was good to ~18Kft, but did not allow repeaters. But I was just digging into the ADC catalog, and there they are; I assume they are a new offering. I know someone at ~40Kft who must have two repeaters, but I've seen only the one. -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close........[v].(301) 56-LINUX Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433
Date: Thu, 11 Feb 2010 20:22:15 -0800 (PST) From: anomalous <kyorei@gmail.com> To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org. Subject: Re: Do you know where there are Teletype machines for sale? Message-ID: <ea31e678-7d89-4bb3-9483-b8f2b8e2b578@k2g2000pro.googlegroups.com> On Dec 14 2009, 2:32 am, Bill Horne <bill.rem...@this- too.billhorne.homelinux.org> wrote: > I subscribe to a mailing list for Teletype users, called GREENKEYS. > > One of the readers posted a request for info on whether a Model 15 > Teletype is available for purchase, and it got me wondering if any of > the Digest's readers have knowledge in this area. > > Does anyone know of any repository of Teletype machines? I can't help > but wonder if some Baby Bell has a warehouse full of them, and there's > a fair number of users who'd be delighted to get at them. > > Thanks for your time. > > Bill I have a Model 15 that has been in storage for years. The plan was to get it up and running again one day, but given how long I've had it and not touched it - this is pretty unlikely. I was thinking of offering it for sale on ebay (having no idea how to get in touch with a more specific interest group). The catch is, while it is a black US model (i.e., it needs 110v), it is located with me, in Australia. I dont know if these are rare enough that someone would fork out for the shipping, but if anyone is interested, please contact me. Thanks, ben
Date: Fri, 12 Feb 2010 06:34:40 +0000 (UTC) From: wollman@bimajority.org (Garrett Wollman) To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org. Subject: Re: ISDN (was: Re: Two 1A ESS COs to be Replaced in 2010; 59 Remain ) Message-ID: <hl2spv$2jc4$1@grapevine.csail.mit.edu> In article <4B74BB00.1000705@thadlabs.com>, Thad Floryan <thad@thadlabs.com> wrote: >Cisco 7960 and Polycom IP4000 (conference room) instruments seemed to >be the overwhelming and near ubiquitous favorites. MIT did a big rollout starting two years ago (which I think is still ongoing... something about maintenance renewal on the 5ESS looking to cost $BIGNUM) and chose to go all Polycom. The desk phones -- four-button 550s and six-button 650s -- seem to be pretty decent, and run better software than the now-obsolete IP4000 conference phone. (My lab is getting IP6000s now but we still have mostly 4000s.) A sore point has been compatibility with wireless headsets; it took a lot of complaining before the central phone people would make available a Polycom software load that properly supported current models of headset, and users' existing "handset-lifter" headsets were mechanically incompatible with the Polycom handsets. (We had used AT&T/Lucent/Avaya 7506 ISDN desk sets before the switch.) For a cheap, simple, configurable desk phone, I preferred the Linksys (ex-Sipura) models, but unfortunately, Linksys won't support end-users who have them, and "business" features require use of their proprietary PSTN gateway. I still have one on my desk, but I think it's the last. The Polycoms do have slightly better voice quality, but don't support cool stuff like end-to-end encryption. -GAWollman N.B.: I don't speak for MIT. -- Garrett A. Wollman | What intellectual phenomenon can be older, or more oft wollman@bimajority.org| repeated, than the story of a large research program Opinions not shared by| that impaled itself upon a false central assumption my employers. | accepted by all practitioners? - S.J. Gould, 1993 ***** Moderator's Note ***** Please tell us more about the phone(s) and the choices each offers. I'm especially interested in the encryption tool(s) which each vendor and/or system has available. I'd also like - very much - to know what factors (other than money) drove the cutover: it's very rare for a large organization to make so fundamental a change, so please share what you know about the decision-making process. Bill Horne, who remembers when the Dormphone SxS was in the basement of Walker Memorial and had "pheeping" flags on it.
Date: Fri, 12 Feb 2010 17:51:56 +1100 From: David Clayton <dcstar@myrealbox.com> To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org. Subject: Re: ISDN (was: Re: Two 1A ESS COs to be Replaced in 2010; 59 Remain ) Message-ID: <pan.2010.02.12.06.51.52.740630@myrealbox.com> On Thu, 11 Feb 2010 05:09:48 +0000, John Levine wrote: >>> ... ISDN, at least for me, was indeed "Is Still Doing Nothing". I >>> understand it's still around, but why escapes me, with it's painfully >>> slow speed compared to DSL. > > ISDN is still circuit switched 64K channels, known as B for Bearer > channels. It's a substitute for POTS, not for broadband. > > Since it's digital end to end, the voice quality is better than analog, > and as has been noted you can bond multiple B channels together to get > better fidelity. ISDN lines also have a D channel used for call setup and > (in theory although rarely in practice) moderate speed data, so ISDN > provides a full set of spiffy calling features via the D channel. The ISDN D channel is used in Australia for at least one service by the major telco here, and that is to cheaply transport small amounts of EFTPOS data from retailers to banks via an X25 network that connects to the D channel in the exchange (the Telstra "Argent" product). It saves the cost of an individual data link, but nowadays is being outmoded by secure Internet based EFTPOS links. -- 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.
Date: Fri, 12 Feb 2010 18:26:54 -0500 From: T <kd1s.nospam@cox.nospam.net> To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org. Subject: Re: How do you get your number off a list so that it's gone, gone Message-ID: <MPG.25dfadcc80f51e7e989c82@news.eternal-september.org> In article <6645152a1002101518k5b6344e0w85361cf9c5b6509d@mail.gmail.com>, john@mayson.us says... > I had the same happen. Well sort of. Different parties. I'd get a > call asking for money. The first time they called they informed me > there was a $75 minimum donation. I pointed out I was on the "Do > Not Call" list. They quickly pointed out they're exempt. I > explained I knew that, but I would like them to honor that still. > They told me they didn't have to. I explained that I'm not going to > give them any money and if they continue to call I will not only > never give them money, but I will give money to their opponent and > vote for their opponent. That actually did the trick despite me > living in a conservative county and congressional district in Texas. > Me voting for a Democrat would be as effective as spitting into the > wind. I get all sort of political calls here. The saving grace, Google Voice. I signed up for a number and have it point at my main number. The nice thing is, you can teach Google voice to recognize numbers of people you WANT to hear from. If they call it rings through, if not they're asked to record their name at the tone and then it rings your phone and plays back the name. Based on that you can either accept or decline the call. So now when I go to political sites and they request a phone number, they get the Google Voice number.
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 Bill Horne. 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 moderated by Bill Horne. 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) 2009 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 (7 messages)

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