Pat, the Editor

27 Years of the Digest ... founded August 21, 1981

Classified Ads
TD Extra News

Add this Digest to your personal   or  

Message Digest 
Volume 28 : Issue 180 : "text" Format

Messages in this Issue:
  Re: Number length, was Goodbye to copper? 
  Re: Number length, was Goodbye to copper? 
  Re: Number length, was Goodbye to copper? 
  Re: OT: IFRAME exploit was: Re: Goodbye to copper? 
  Re: Cable TV Broadcast Retransmission Consent Feuds "Ease Up"   
  Re: Goodbye to copper? 
  Re: NANP ten digit dialing, was Goodbye to copper? 
  Copper wire thefts from cellphone towers 

====== 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: Thu, 02 Jul 2009 13:31:55 -0500 From: (Robert Bonomi) To: Subject: Re: Number length, was Goodbye to copper? Message-ID: <HKednTgabJ-GYNHXnZ2dnUVZ_qSdnZ2d@posted.nuvoxcommunications> In article <>, <> wrote: >In a message dated 6/29/2009 11:07:32 AM Central Daylight Time, > writes: > >> Many private PBX vendors were unprepared, in a variety of ways, to >> properly track rapid new code assignments and get their PBX tables >> properly updated. > >Why should PBX's have tables or any information about what area codes >exist? As a general rule, I mean, unless they have their own private >systems and private lines that they want certain area codes routed >over? There are lots of reasons. e.g.: You may have trunk service from multiple carriers, with different rates to common destinations -- you want to route the call via the 'cheapest' carrier, obviously. You may have multiple 'local' area-codes, and want people to be able to do 'local' dialing but *not* be able to dial 'long distance' calls. or international calls. You may want to restrict access to '900' type numbers, because they can cost a *lot* extra. (Care to guess how much in charges a few employees can run up, when they discover they can call dial-a-porn from the phone in the break room?) You may have multiple locations, in multiple area-codes, and implement an 'integrated dialing plan' where you can reach a desk at a remote location _without_ dialing the full phone number. This does not require dedicated trunks between locations, it can be done over the PSTN, with appropriate digit absorption and insertion in the dialing process. *BUT*, you gotta know which area-code to insert for a cross-NPA call. :) The more 'smarts' you have in the local equipment, the more flexibility you have in controlling operations. Many people don't "absolutely NEED" all of that flexibility, but a surprisingly large number _can_ "put it to good use" (i.e., do things that save themselves money) to greater or lesser degree. ------------------------------ Date: Thu, 2 Jul 2009 19:29:14 EDT From: To: Subject: Re: Number length, was Goodbye to copper? Message-ID: <> In a message dated 7/1/2009 5:42:14 PM Central Daylight Time, writes: > And for those scratching their head about "billing location", I mean > the cellphone-equivalent location of a CO for toll-charge > determination. A "rate center," which may or may not be the location of a CO. Wes Leatherock ------------------------------ Date: Thu, 02 Jul 2009 20:20:41 -0700 From: Thad Floryan <> To: Subject: Re: Number length, was Goodbye to copper? Message-ID: <> On 7/2/2009 7:58 PM, wrote: > In a message dated 7/1/2009 5:42:14 PM Central Daylight Time, > writes: > >> And for those scratching their head about "billing location", I mean >> the cellphone-equivalent location of a CO for toll-charge >> determination. > > A "rate center," which may or may not be the location of a CO. Thank you for the terminology clarification! Learn something new every day -- that's why I've been mostly a lurker here for several decades. :-) ------------------------------ Date: Thu, 02 Jul 2009 10:33:07 -0500 From: (Robert Bonomi) To: Subject: Re: OT: IFRAME exploit was: Re: Goodbye to copper? Message-ID: <A8mdnTEEz4-uTtHXnZ2dnUVZ_jKdnZ2d@posted.nuvoxcommunications> In article <h2gvhk$n4o$>, danny burstein <> wrote: >In <f8adnVw7y_6zJtbXnZ2dnUVZ_s6dnZ2d@posted.nuvoxcommunications> > (Robert Bonomi) writes: > >>In article <>, >>tlvp <> wrote: > >>> One just needs a "no IFRAMES, please" option in one's browser. >>> Which browsers, apart from IE, offer such an option? > >>The latest version of the NoScript plug-in for Firefox does. <grin> > >Otoh, the latest version of Firefox is "location aware", and >can send that info (of where you are) to a website on request. > >Yes, it's "opt in", but that's for today. Wat'cha wanna bet there >will soon be other programs using this info w/o your knowledge... Well, since Firefox is 'open source', it's pretty well guaranteed that there will always be a way to turn this "feature" off -- if its not in the stock distribution then there _will_ be an add-on to do it. BTW, it isn't just Firefox. Google makes the same capability available for MS-Internet Explorer, and for embedded IE for a bunch of mobile devices with 'Gears' installed. Google's entire 'Gears' project is also open-source, so, if anybody decides to do a 'always on' variation, it is a safe bet that some 'rebel' will build an add-on to disable it. <grin> ------------------------------ Date: Thu, 2 Jul 2009 16:14:58 +0000 (UTC) From: "Adam H. Kerman" <> To: Subject: Re: Cable TV Broadcast Retransmission Consent Feuds "Ease Up" Message-ID: <h2ime1$do3$> Neal McLain <> wrote: >This article (including comments from me writing as texascableguy) >continues at: > >In 1992, Congress enacted the Cable Television Consumer Protection and >Competition Act of 1992. This act gave broadcast station licensees >control over cable-system carriage of their signals. Under this Act, >each licensee has the right to choose two options with respect to any >give cable system: >- MUST CARRY: The cable system must carry the signal under technical >rules specified by the FCC. However, the station cannot charge for the >use of its signal. >- RETRANSMISSION CONSENT: The cable system is required to obtain the >permission of the licensee. The licensee is free to demand compensation >or impose other requirements. >Most large regional independent stations and major network affiliates >usually elect retransmission consent. Less popular stations usually >elect must carry. How do these rules apply to each multi-plexed programming stream of a digital broadcaster choosing [to invoke the] "must carry" [option]? Or does it apply only to the the first subchannel? If that subchannel is HD and the cable system offers HD channels, must it be carried as HD? An independent broadcaster in Chicago owns a full power license and several low power licenses. It has mixed and matched programming over the years, typically introducing new program concepts on one of the low power stations before simulcasting it or moving it [to] a subchannel of the full power digital station. Does simulcasting via one of their low power stations give them additional clout when negotiating carriage because the law gives them additional privileges for owning more licenses? They've complained for years that DTV and Dish won't carry all programming streams, even the ones simulcast on one of the low power stations. ------------------------------ Date: Thu, 2 Jul 2009 16:37:09 +0000 (UTC) From: "Adam H. Kerman" <> To: Subject: Re: Goodbye to copper? Message-ID: <h2innk$gvt$> PV <> wrote: >Dan Lanciani <> writes: >>>You are absolutley correct with regards to regulation of services, not >>>facilities/technologies. How a circuit is designed and how it is carried to >>>the subscriber is not a tariff item, unless the customer is an IEC or CLEC. >>Aren't tariffs (in at least some areas) fairly explicit about the interface >>at the demark point, though? Does POTS as typically tariffed allow the >>telco to require the customer to supply power for their equipment? >Also, wouldn't a copper drop be outside of the demarc anyway? What >business is it of the customers if they clip it? If it's ever needed again, >it will be the telco's job to put in a new one. There is no good reason >that they should be forced to maintain redundant cable runs. >I don't see this being any different than a cable company removing the run >to your house if you drop their service. Who cares? I'd rather that they do >that, because it's going to need to be replaced if needed again after years >of non-use anyway. * I agree with you. Yank out unused drops. Insullation exposed to the elements has limited life. Install new for new subscriber. Where I live, years ago, the phone company did a seriously messed up installation of the drop serving my apartment. Instead of following the path of electric lines and entering the basement through that wall, it enters under a porch and through a tube that does a very nice job of channeling rainwater into the building. I'm not a subscriber, so I wish they'd remove it. One of the two pairs in that drop is still live! Strangely, there's unused vertical conduit on the outside of the building near the drop for electricity, so I would imagine that it was installed for telephone many years ago. Cable technicians are notorious for bad work. My building has two units. The cable drop serving the other unit went bad. Then the service to my unit went bad. A technician on my service call discovered that service to the other unit was now being split off the drop to my unit. The technician on the service call to the other unit hadn't replaced the bad drop! She wasn't trained in replacing drops and so she ordered work to be performed by another installer. That guy installed a new drop to my unit but refused to remove the bad drop. A few weeks ago, a new couple moved into the other unit and subscribed to cable. They changed some of the cable runs on the outside of the building. Rather than clipping them directly to the masonery, they tied them to the bad drop. A few days later, the clips holding the bad drop to the brickwork came off the wall and it's all hanging loose. ------------------------------ Date: Thu, 02 Jul 2009 14:03:00 -0500 From: (Robert Bonomi) To: Subject: Re: NANP ten digit dialing, was Goodbye to copper? Message-ID: <SdOdnfcSwb75mdDXnZ2dnUVZ_sKdnZ2d@posted.nuvoxcommunications> In article <khL1m.797$Ei4.512@newsfe13.iad>, Sam Spade <> wrote: >John Levine wrote: > >>>Again, a person is a person and despite all the arguments along these >>>lines, many (many) other countries have managed such a change without >>>too much trouble at all - certainly far less trouble than the >>>opponents of theses things said would occur. >> >> >> Once again, you are (wilfully?) missing the main point. The >> technology in North American phone switches is different from that in >> the rest of the world. >> >> The inter-switch signalling in Australia was already set up to handle >> numbers of differing lengths, so it was not a big deal to change >> lengths of numbers incrementally, since those longer numbers didn't >> affect the switches that don't handle the numbers being changed. In >> North America, the 3+3+4 format is wired into the hardware (and now >> into the switch software.) Like it or not, longer numbers will >> require changes to every phone switch in the continent. That's the >> real issue, not the consumer answering machines, stationery, and other >> junk. >> >> We'll have to make numbers longer at some point, perhaps 30 years from >> now, and the telcos are thinking about how to do it, but it'll be a >> huge project. >> >> R's, >> John >> >The hard-wired switches are gone from the U.S. and (for the most-part) >Canada. > >How long have we had stored program controlled end office switches now? >They became common by 1980. And, they enabled subscriber dialing of >international numbers of varying length with delimiting by timeout or >DTMF "#" > *sigh* The 3+3+4 number format 'logic' is embedded *VERY* deeply into the architecture of the software of the aforementioned 'stored program controlled' C.O. switches in the U.S. Data structures (e.g. routing tables) are sized based on the 'assumption' of that format; code 'assumes' _fixed_length_ break-out of the sections of the full number; etc., etc., ad nauseum. It's like the Y2K issue -- making the individual changes was generally _not_ a big task (although there were exceptions to that); *FINDING* all the places where things had to be changed was a whole nuther matter. The 3+3+4 number format _is_, for practical purposes, "hard wired" into the control program software. It isn't that the switch "can't handle it (a longer, differently formatted number)" -- it *can*. *All* modern switches are required to accept dialed-digit strings of at least 16 (19??) characters. *BUT* they "don't know what to do with it" other than hand the entire thing off (what is called an 'opaque' object -- don't know, nor care, anything about the internal structure) to a 'foreign' switch based on the first (up to 4) digits after the international-dialing prefix. A local CO probably doesn't even look at _those_ digits, it sees the international ("011") prefix, and "passes the buck" to the toll tandem, which may do minimal parsing of the country-code (if nothing else to determine whether to route via East or West Coast, or towards Central/South America. There's also more than 'just' the C.O. switch that has to be considered. Courtesy of 'local number portability', there is a database look-up ("dip") that has to be done for effectively every call, to find out 'where' that must be sent for delivery. That database, for performance reasons, requires a fixed-length 'key' (the phone number) field. Increasing the size of the key is a relatively minor task, but it requires a 'flag day' cut-over, *AND* assurance that the protocol for querying the database can handle the extra digit(s) properly. Also, significant parts of the _hardware_ design are also predicated on certain economies based on the specific _scale_ of the elements in th 3+3+4 design. This constrains 'where and how' you can stick extra digits into the dial-string. ------------------------------ Date: Thu, 2 Jul 2009 07:35:08 -0700 (PDT) From: To: Subject: Copper wire thefts from cellphone towers Message-ID: <> The Phila Inqr reported that people were arrested stealing copper wire from a cell phone tower. See: Apparently they were stealing lightning protection wire which would not immediately affect service or cause an alert. But of course if lightning hit the tower it'd get knocked out. Copper and other metallic scrap is selling at a high price and people are stealing it. In the 1970s, the Bell System began to pre-wire new houses, putting 4 conductor wire in each room in case a telephone extension would be subsequently desired. I wonder how much unused copper wire is out in homes and businesses. I don't believe Bell ever removed wire, including thick multi- conductor cables, from a business that disconnected its internal phone system; sometimes they even left behind key telephone units. However, scrap wire in new installations and in central offices was always savevd and recovered. Is the standard today 6 conductor? Is that wasteful of conductors? ------------------------------ 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 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: 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 (8 messages) ******************************

Return to Archives**Older Issues