30 Years of the Digest ... founded August 21, 1981
The Telecom Digest for September 27, 2011
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Date: Sun, 25 Sep 2011 17:15:05 -0700 From: Steven <firstname.lastname@example.org> To: email@example.com. Subject: Re: mobile wifi hotspots, was Strange new at&t rumors Message-ID: <firstname.lastname@example.org> On 9/25/11 3:25 PM, David Clayton wrote: > On Sat, 24 Sep 2011 18:30:19 -0700, Steven wrote: > ....... >> That was one of the questions I asked and was told each room had its own >> receiver, I pointed out that even if that was a fact, then mine should >> have been turned off, so if it was on it still was not my problem. plus it >> could not have been that short of a range since mine at home works up to >> 100 feet. I showed the manager my computer with the card and my Hot Spot >> showing that it was linked to its own, I also showed him the hotels hot >> spots and each one was locked and you needed a code to get it to a allow >> use, by the way, the code was the room number, end of problem. > > So if the "Hot Spots" are not set to the same frequency (or you disable > the one in your room), then you can connect to another room and rack up > charges on their account? > I have no idea, all I know is I was using my own. When I travel I use mine when I can even if is free, I just don't like the security or lack of on open ports. -- The only good spammer is a dead one!! Have you hunted one down today? (c) 2011 I Kill Spammers, Inc. A Rot in Hell Co.
Date: Mon, 26 Sep 2011 08:44:29 -0400 From: Monty Solomon <email@example.com> To: firstname.lastname@example.org. Subject: Want More Information? Just Scan Me Message-ID: <email@example.com> Want More Information? Just Scan Me By STEPHANIE ROSENBLOOM September 21, 2011 DURING New York Fashion Week earlier this month, Quick Response (QR) codes - square, checkered symbols that can be scanned with one's smartphone - were as omnipresent as chunky black booties. They were on cookies doled out by Tiffany that, when scanned, revealed an invitation to a concert with Leighton Meester. They were on a pink Barbie-themed bus, and on doll displays in stores that could be scanned for a chance to win designer clothes. And they were on postcards for a "fashion hunt" with the Madison Avenue Business Improvement District and the blog Madison Avenue Spy. Weeks earlier, a model walked a runway in Barcelona with a QR code emblazoned on the bodice of her Frans Baviera gown; meanwhile, a company called Skanz began selling silicone bracelets embellished with QR codes that enable anyone with a smartphone to scan your wrist and instantly access a Web page with your contact information, social media links, even favorite photos and videos. In other words: you've become a human hyperlink. ... http://www.nytimes.com/2011/09/22/fashion/qr-codes-provide-information-when-scanned.html ***** Moderator's Note ***** Does anyone remember Cue-Cat? Bill Horne Moderator
Date: Mon, 26 Sep 2011 11:03:05 -0400 From: Fred Goldstein <firstname.lastname@example.org> To: email@example.com. Subject: Re: LightSquared claims that it solves GPS interference with new device Message-ID: <20110926150309.DDCCA34B46@mailout.easydns.com> Bill Horne wrote, >... >This "solution" worries me a lot. Here's why: > >1. Many LECs make extensive use of GPS timing devices to synchonize > the various components in their networks. If LightSquared's '4G' > system causes interference to those GPS receivers, major outages > are possible, and they'd probably be intermittent and thus hard to > identify. > >2. I didn't see anything in the article about "non precesion" GPS > receivers, and if LightSquared isn't providing any solution to the > problem of interference to "consumer grade" devices, that means > that the Garmin GPS on the dashboard of my car, and similar units > in millions of other vehicles, might be made obsolete. Those two issues are linked, and solved. LightSquared will not interfere with non-precision GPS or timing devices. The reason is that LightSquared's spectrum includes two 10 MHz bands, only one of which is hard up against GPS. The original plan was to use both bands, and the upper band would have overloaded the front ends of most cheapo GPS receivers out there, because manufacturers built them to the interference in the field when built, not what the FCC had authorized but which wasn't yet in use (i.e., LightSquared's ATC). Because of this problem, LightSquared has agreed to put off using its upper band for a few years, and the lower band doesn't cause problems to timing systems or even el cheapo GPSs. High-precision GPS uses an additional signal, which is what the latest fix is about. danny burstein <firstname.lastname@example.org> added, ... >Similarly, while tests of, say, 10 "smart" LightSquared units >working alongside 50 standard GPS'es may work ok in the lab, >that's very, very, different from having 10,000 of them in >the field, often outside, with weather and power spikes and >water and bird poop. > >If we make up the number that one percent of them will go >kablooey each year, that's a pretty ugly number of facilities >that will cause problems... The base stations, not handsets, are the problem. Base stations have much higher transmit power, after all. No GPS will be near many of them at a time. Interference is caused by overload, which happens when close to a high-powered transmitter, not a low-powered mobile (unless it's a really bad receiver or extremely close). Using the lower L-band, a GPS can drive right under a tower and almost certainly still work. The higher L-band will cause problems unless the receiver vendors spend a few dollars (just a small few, I suspect) on tightening up their equipment. -- Fred Goldstein k1io fgoldstein "at" ionary.com ionary Consulting http://www.ionary.com/ +1 617 795 2701
Date: Mon, 26 Sep 2011 17:46:12 +0000 (UTC) From: email@example.com (Garrett Wollman) To: firstname.lastname@example.org. Subject: Re: LightSquared claims that it solves GPS interference with new device Message-ID: <email@example.com> In article <20110926150309.DDCCA34B46@mailout.easydns.com>, Fred Goldstein <firstname.lastname@example.org> wrote: >The higher L-band will cause problems unless the receiver vendors >spend a few dollars (just a small few, I suspect) on tightening up >their equipment. Does the FCC (or another agency) have any legal authority to force them to do so, or are we simply stuck with the situation as it now stands? -GAWollman -- Garrett A. Wollman | What intellectual phenomenon can be older, or more oft email@example.com| 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
Date: 26 Sep 2011 14:49:29 -0400 From: firstname.lastname@example.org (Scott Dorsey) To: email@example.com. Subject: Re: LightSquared claims that it solves GPS interference with new device Message-ID: <firstname.lastname@example.org> Garrett Wollman <email@example.com> wrote: >In article <20110926150309.DDCCA34B46@mailout.easydns.com>, >Fred Goldstein <firstname.lastname@example.org> wrote: >>The higher L-band will cause problems unless the receiver vendors >>spend a few dollars (just a small few, I suspect) on tightening up >>their equipment. > >Does the FCC (or another agency) have any legal authority to force >them to do so, or are we simply stuck with the situation as it now >stands? Not really. The FCC can regulate emitters, but has very little power to regulate receivers. I am sure AM radio stations would LOVE for the FCC to mandate that AM radio manufacturers have a certain minimum sensitivity level, minimum IF skirt slope, etc. But they don't, so most AM radio manufacturers make crap that doesn't work very well. There is no law against making crap that doesn't work very well. There is no law saying that your product has to work with a given amount of off-channel interference, only that it "must accept" that interference. Frankly, I would just be happy if the FCC would start enforcing Part 15 regulations, and prevent manufacturers from selling junk that clearly does not meet Part 15. The LEAST of our worries is receivers that accept interference from sources legal under part 15, considering how many sources that are illegal under part 15 can be found in every discount store. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis."
Date: 26 Sep 2011 14:51:21 -0400 From: email@example.com (Scott Dorsey) To: firstname.lastname@example.org. Subject: Re: Where does digital phone service hand off toll-free calls? Message-ID: <email@example.com> Adam H. Kerman <firstname.lastname@example.org> wrote: >If a subscriber has digital phone service, where would calls to toll-free >numbers be handed off? Are they handed off to the local telephone company >at the closest co-lo to the physical location of the digital server that >provides service to its subscriber? Are they handed off to the central >office serving the polygon of the rate center (or wire center if different) >based on (what the digital phone service provider thinks is the) service >address, which could involve back-hauling traffic? Or do digital phone >service networks interface directly with some long distance providers >offering toll free service? I'm not sure what you mean. Our PBX has a T-1 to the local telco, and it also has a T-1 to a long distance provider. We can hand it off to either one, as the PBX software sees fit. This is the miracle of the digital age. >20 years ago, I recall working in an office in which we used "9" as a >trunk prefix to make long-distance calls, but "8" for local and toll-free >calls. Now the PBX is smart enough to figure out which of multiple routes is cheaper, all by itself. In fact, some folks might have multiple trunks to different LD providers and route based upon which provider is cheaper on a given call. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis."
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