29 Years of the Digest ... founded August 21, 1981
The Telecom Digest for May 05, 2011
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Date: Wed, 04 May 2011 01:15:04 -0700 From: Sam Spade <email@example.com> To: firstname.lastname@example.org. Subject: Re: The most profound question about cellphones ever. Message-ID: <Kp-dnVpsaLmUllzQnZ2dnUVZ_hqdnZ2d@giganews.com> Wes Leatherock wrote: > --- On Sat, 4/30/11, Sam Spade <email@example.com> wrote: > > >>Zorbampano wrote: >> >> >>>Is it okay to charge one's cellphone with it turned on? The manual >>>says the cellphone should be turned off when charging. So, will it >>>charge even if it's turned on? And if you charge it with it turned >>>on, can you receive calls? >> >>None I've owned have had that limitation that I am aware of. All of >>mine have been on charge when in the car. > > > A sales representative for Cingular (now AT&T) told me she always > plugs in the car chaerger and plugs her phone into it, turned on, > whenever she gets in her car. I've been doing that since my second phone. The first one in 1984 had a base installed in the car, so when mounted to the base it was receiving vehicle power. That educated me the same was as the Cingular rep was educated. Why not be on "ship's" power whenever possible?
Date: Wed, 04 May 2011 07:20:48 -0700 From: Sam Spade <firstname.lastname@example.org> To: email@example.com. Subject: Re: Busy trunks--subscriber behavior Message-ID: <LfudnW3r6shd_VzQnZ2dnUVZ_gednZ2d@giganews.com> Lisa or Jeff wrote: > These days it is very rare to run out of trunks or switching > capacity. However, during emergency situations, such as after heavy > storms or other natural disasters, or other major emergencies, there > may be a temporary overload on telephone facilities. > > If this happens the switches may get overloaded. If a caller hits a > busy signal (of any type), they'll try again very quickly. These > unsuccessful call attempts represent a load on a switch. > > Years ago a flood of call requests to an ESS might cause the entire > switch to fail; I'm not sure if today's switches have the same > limitation. > > Some time ago the Bell System Technical Journal did a study on > subscriber behavior out of concern that common control offices would > be flooded in special situations. While somewhat dated, it is > interesting. > > http://www.alcatel-lucent.com/bstj/vol27-1948/articles/bstj27-3-424.pdf > My recollection is that, like everything else, the No.1 ESS was much more sophisticated at handling such issues than equipment studied in that article. If there were an overload in a 1 or 1A ESS the ordinary subscriber would be denied dial tone. Certain priority subscribers could still be provided dial tone. If a lot of subscribers remained off-hook, no harm, no foul, unlike a No 5 XBAR, which could crash given sufficient permanent off-hooks. The No. 1 and 1A would eventually dump the permanent off-hook to the receiver off-hook (ROC) routine, then to suspend status ("dirty" battery). If traffic were really busy, the ROC tone would not be provided. Nonetheless, the switch would be more apt to eventually provide dial tone to a subscriber who remained off-hook (that is, until ROC kicked-in) as opposed to a subscriber who would repeatedly plunge the switch-hook. No doubt the No 5ESS would handlle the situation much the same because of similar design policies for such matters. All of this presumes no major damage to the switch itself or its trunk frams. The loss of a line frame was insiginificant except for the subscribers assigned to that frame. (line module on a 5ESS I believe.)
Date: Wed, 4 May 2011 09:46:03 -0700 (PDT) From: Lisa or Jeff <firstname.lastname@example.org> To: email@example.com. Subject: Toll switching history articles BSTJ Message-ID: <firstname.lastname@example.org> The September 1952 Bell System Technical Journal had a series of articles on the development of nationwide toll telephone service: "Automatic Switching for Nationwide Telephone Service Clark, Fundamental Plans for Toll Telephone Plant, Nationwide Numbering Plan, and Automatic Toll Switching Systems." Interesting stuff. Also included is a discussion of design details for reliability reliability--a layperson would not realize all the minute issues that must be considered for reliability; as well as a report on semiconductor electrical noise. Issue table of contents: http://www.alcatel-lucent.com/bstj/vol31-1952/articles/bstj31-5-976.pdf
Date: Wed, 04 May 2011 13:51:03 +1000 From: David Clayton <email@example.com> To: firstname.lastname@example.org. Subject: Re: Dutch Police Used TomTom's GPS Data To Target Speeders Message-ID: <email@example.com> On Sun, 01 May 2011 15:33:14 -0400, Monty Solomon wrote: > > Dutch Police Used TomTom's GPS Data To Target Speeders > > By Eyder Peralta > April 29, 2011 > > Over the past week, U.S. consumers have been talking about their smart > phones keeping tabs on their location. In the Netherlands, another kind of > GPS scandal is brewing: The government bought aggregate global positioning > system data from the automotive navigation company TomTom and then used it > to install speed cameras in places where drivers are most likely to speed. > > ... And how does this become any sort of "scandal" whatsoever? -- 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: Wed, 04 May 2011 21:31:14 +0100 From: Stephen <firstname.lastname@example.org> To: email@example.com. Subject: Re: Busy trunks--subscriber behavior Message-ID: <firstname.lastname@example.org> On Tue, 3 May 2011 09:29:07 -0700 (PDT), Lisa or Jeff <email@example.com> wrote: >These days it is very rare to run out of trunks or switching >capacity. However, during emergency situations, such as after heavy >storms or other natural disasters, or other major emergencies, there >may be a temporary overload on telephone facilities. > the biggest traffic surges are literally man (or possibly teenager) made - in the UK the last one i heard about was due to tickets to a Pop concert going on sale.... >If this happens the switches may get overloaded. If a caller hits a >busy signal (of any type), they'll try again very quickly. These >unsuccessful call attempts represent a load on a switch. and modems can be even worse..... > >Years ago a flood of call requests to an ESS might cause the entire >switch to fail; I'm not sure if today's switches have the same >limitation. 1 option in switches such as DMS 100 is "call gapping" which AFAICT limits the new connection rate sent across a trunk. > >Some time ago the Bell System Technical Journal did a study on >subscriber behavior out of concern that common control offices would >be flooded in special situations. While somewhat dated, it is >interesting. > >http://www.alcatel-lucent.com/bstj/vol27-1948/articles/bstj27-3-424.pdf -- Regards firstname.lastname@example.org - replace xyz with ntl
Date: Wed, 04 May 2011 12:09:50 -0500 From: Neal McLain <email@example.com> To: firstname.lastname@example.org. Subject: DSL Reports: AT&T Caps Have Arrived Message-ID: <4DC1885E.email@example.com> 150-250 Monthly Caps, $10 Per 50 Gigabyte Overages by Karl Bode Monday 02-May-2011 Back in March we exclusively were the first to report that AT&T would be imposing usage caps and overages on their terrestrial broadband users. Those caps have officially arrived, with DSL users now facing a 150 GB monthly cap, and U-Verse users now facing a 250 GB monthly cap. Both DSL and U-Verse users must pay $10 per every 50GB above the cap they travel. As our original report noted, only users who exceed the new usage cap three times -- across the life of your account, not per month -- will be forced to pay these new per byte overages. http://www.dslreports.com/shownews/ATT-Caps-Have-Arrived-114012
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