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Slashback: Privacy, Spectrum, Location
Sir, you just need to trust us. geekee writes "An article on CNN claims that the proposed passenger-screening system for air travelers is much more innocuous than previously claimed. Now it is claimed that the Transportation Security Administration "will not view credit records, traffic violations or other personal data", according to Admiral James Loy. He also claims records of travel will not be maintained. "Airline reservation agents would provide a traveler's name, address, phone number, date of birth, and travel plans to the TSA, which would then check that information against a variety of commercial databases and an FBI watch list.", according to TSA spokeperson Heather Rosenker."
Thinking of the children means more than hiding their eyes. Jim Tyre writes: "You pointed out that my censorware.net piece ["CIPA Before the Supreme Court"] provided a nifty link to where the official supreme court oral argument transcript would be when available online. It's now available."
What's good for the mercantilists ... wait, no doesn't have the same ring. Lawrence Lessig says that the current radio spectrum is vastly underutilized, and that new technology can extract much more use from it, creating a true radio commons. Zo writes to point out that many Salon readers disagree: "Radio waves, bandwidth, the spectrum. . .Don't we know *anything* for sure?
Sir, these books smell fine ... what's the catch?
silentbozo writes "Avid Slashdotters will remember the Baen Free Library, which puts up free web versions of Baen titles for ANYONE to download and read without having to mess around with encryption and DRM. They went a step further with this experiment last fall with the release of David Weber's War of Honor which had a bunch of novels in html, rtf, doc, palmdoc, and othe formats on CD (bound into the hardcover), which you could copy and give away to anyone. Well, they're at it again. In May, they'll have another CD for those of you who didn't get War of Honor, bound into John Ringo's Hell's Faire.
I got hooked reading John Ringo's books after browsing through my copy of the War of Honor CD... and it's a great way of catching up on the previous books in the series. Hell's Faire looks really good - I personally am looking forward to finding out what happens to the O'Neals as they fight the Posleen on Earth, and to the crew of Bun-Bun... Eat anti-matter Posleen-boy!"
As secure as ... well, you pick. Anthanos writes "pGina [http://pgina.xpasystems.com], a modular authentication framework for Windows, has come a long way since it was last noted on /. nearly a year ago. Since then a full-fledged LDAP plugin, PAM plugin, and chaining have all become part of the feature set. The kicker is the recently released Slashdot plugin, which allows authentication of Windows clients with... yup you guessed it, Slashdot Accounts! XPA Systems has even begun offering services revolving around this GPL product. Seems this may be the solution for people looking to merge authentication of Windows clients with MacOSX, Solaris, and other *nix boxen."
Let's see a handheld that uses both, please ... Mattias Östergren writes "Well aware of the risks with dependency of GPS the European Space Agency (ESA) have developed their own satellite navigation system, EGNOS. EGNOS is more accurate than GPS and the signal also tell you how much it could be off.
The first reference station have just been installed on the roof of the Land Survey in Gävle, Sweden. There is a Swedish press release about it."
(Actually, the existing setup is sweet, but 5cm would be much sweeter.)
It has to do with statistics. Theoretically, the more information you have per data point, and the more datapoints you have, the more accurate your results are.
:) ).
The problem is, if you have too much information per datapoint, you start getting false positives.
Think of it like your Bayesian spam filter(God, I LOVE Moz 1.3!)...the longer you train it (the more spam messages you feed it), the better it will be at recognizing the types of messages you give it.
However, if you, say, start feeding it messages from your ex-spouse, it will start homing in on on other stuff. Possibly personal mail, or maybe legal notifications (depending on your situation.
What's this Submit thingy do?
1) They said they were NOT doing credit checks.
2) OBVIOUSLY this is more than just deciding if a single individual is "secure" for a single flight. They are attempting to track individuals that are on "lists". If a suspected terrorist gets on a plane, the FBI now has till that plane lands to decide if they want to pay him(her) a visit or not. If 20 of them all get on planes in one day to one location, well then...
As an RF/Microwave Engineer, I deal with the problems with RF interference daily. A recent article I saw online lauded the participation of ham radio operators in disaster situations including the World Trade Center relief operation.
Imagine thousands of devices and gadgets emitting radiation on random frequencies, and you can see the problems that might arise in critical communication situations. The background noise level at HF frequencies is already very bad due to consumer devices. I would hate to see it get any worse.
Perhaps I just don't get it, but I am having trouble figuring out why anyone (outside of a small subset of the population) would need accuracy less than 50 feet or so. I suspect people that really need accuracy greater than this currently have the tools to achieve such accuracy. It's not like most people are letting their GPS device drive their vehicles or something. Plus for people that need better accuracy, there are means by which to get it, depending on how much you want to spend.
But, as I said earlier, perhaps I just don't get it....
People are more violently opposed to fur than leather
because it's safer to harass rich women than motorcycle gangs
There is no reason not to rely on the US GPS system...
Really? I would beg to differ. I say this under the context that the US taxpayer bought and paid for the GPS, so they have no duty to guarantee any level of service, however some of the arguments against a European GPS system seems to be along the lines of the kid who's taking his ball home and gets angry when he sees that they got their own ball.
Political sidenote: I love how the administration has set up a whole slew of ridiculous propaganda techniques to give the illusion of a dangerous enemy to enrage the public into a president supporting, pollster responding public. Want to invade someone? Up your dubious "threat level" as if you are responding to some overt immediate threat from the deadly enemy. Want to pretend that your enemy is more powerful than they really are? Talk about disrupting GPS, lest they guide their 1960s era Soviet T55s by it... Eurasia...europa...who knows anymore. I am making no comment about the righteousness of this war, but I hope that people can see through these shallow manipulations.
Your credit actually seems to have a lot to do with a lot of things. Poor credit is correllated with a lot of things. For example, those with poor credit are more likely to have auto accidents and file claims. In fact, one insurance company I know had studies indicating that credit history was the most important predictor of future auto claims - even moreso that prior auto claims. Amazing.
This makes a certain amount of sense. While many people do end up in credit trouble through no fault of their own (catastrophic medical bills, job loss, etc), very often people who end up with poor credit do so because they are unable to properly manage their fiances. Perhaps this indicates they are also irresponsible in other areas of their life.
You misunderstand the arguement. The frequencies are far from random, and the equipment is designed to expect frequency hoping, amongst other things. That is the most basic step toward a better utilized spectrum, one that has been used since WWII.
-R
One noteworthy thing about the CD-ROM that's not mentioned in that orientation is that it will include a (partly-)OGL D20 RPG based on the Aldenata books, which you can currently find hosted in rich text form at Alldenata.net under the link marked "rules." (I'm not entirely sure why the spelling of the aliens changed between the first few books ("Alldenata") and the most recent one ("Aldenata"); nobody on the John Ringo Baen Bar group seems to want to talk about it.)
Editor Emeritus and Senior Writer, TeleRead.org
Where the hell do you get your info?
Most modern radios (I mean those in cell phones/WiLan) use a combination of these techniques. Furthermore you have a serious lack of understanding of the technologies you mentioned.
First, CDMA is considered on the forefront of spread spectrum technologies today, TDMA is old-hat. Second, TDMA is not infinitely scalable. If you have shorter time slices, you increase the bandwidth. There is no free lunch, you have to use bandwidth to send data. You can sometimes increase efficiency, but nothing is infinitely scalable.
Really, put the infinitely scalable TDMA system in the engineering hall of fame with the perpetual motion machine and brickwall filter.
[TDMA] is an immensely powerful technique, and one that is infinitely scalable. It's only limitation is the speed of our electronics, which can and should maintain it's exponential speed curve.
This is why the spectrum is underutilized.
You do realize that as sampling rate goes up, spectrum use (bandwidth) goes up, right?
Any given region of spectrum can only carry so much data, any way you slice it. Power, noise/clutter, and bandwidth combined determine (and limit) data rate.
This comment follows a rant which ironically ignores most modern radio breaktrhoughs: packet routing and frequency hopping on low power devices to create a network with far greater bandwith than a single transmitter per frequency set up that's current.
Mesh routing schemes break down in highly populated areas - you end up with too many messages needing to be routed by any given node, and the fraction of node bandwidth used for that node's messages dropping like a rock.
Relation is a fun exercise in calculation that takes about 2 minutes.
The only way around this is to link to a backbone and strongly limit transmitter power, which sort of torpedoes the "let's stop regulating the spectrum" argument.
You can do point-to-point without a backbone, but only with a large dish or a large *wired* array of transceivers.
There's also have a sort of space division multiplexing- i.e. using directional antennas. That concept is used on TV aerials among others.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"Next time you are in your airplane flying around in poor visibility, you might notice that there are numerous round gauges and dials there in front of you in the cockpit. Theses are called instruments, and by reading them correctly, you will be able to figure out where you are going. In visibilty that is so poor that you cannot look out and see the world around you, you will be operating under instrument flight rules, or IFR. Hope you are certified for IFR flight. It is interesting to note that IFR has existed much longer than GPS, and in fact a GPS reciever is not one of the instruments that your craft must posess in order to operate under IFR.
My whole point is that people that need accuracy have it now, and will continue to have it. Its just not free.
Perhaps not, but in this regard, we are equals.
People are more violently opposed to fur than leather
because it's safer to harass rich women than motorcycle gangs
This is assuming no triangulation of source. If I treat my input as a point, I get interfernce at any given frequency because I treat all transmission as coming from and arriving to this imaginary space. (this is the way traditional broadcasting is treated)
If on the other hand I treat my input as a three dimensional space all of a sudden I can have as many broadcast sources as my ability to process them can tolerate. I can distinguish signal based on directionality, though I have new concerns like multi-path signals and two sources coming one behind the other.
If you have a receiver that is smaller than the signal wavelength (i.e. is an omnidirectional point receiver, moving or non-moving), you will end up not having enough information to disambiguate sources when the system is beyond the capacity limit that I outlined previously. This is easy enough to demonstrate; the total amount of information available to you is the amount that one transmitter could produce, assuming that signal generation and reception fidelity are equivalent. Trying to distinguish between multiple sources dumping as much information as they can into the environment requires pulling extra information out of nowhere, which you aren't able to do.
Knowledge of the location of the sources, or of where signal-affecting surfaces are in your environment, or of the motion of your receiving unit (for synthetic aperture tricks) makes signal processing easier when you're below the saturation point, but doesn't help you when the total amount of information you're trying to extract is greater than that received.
If you feel I'm overlooking something, then let's consider an artificial case that's easy to analyze. Assume straight sampling of signal data from zero to a given frequency with a given number of detectable data levels (linear for easy analysis). Assume sources and receivers are point sources (which they are if they're smaller than a wavelength). Do whatever you like with the environment and with data processing, and show me how you'd get one receiver to reconstruct the continuously-streaming signals from two sources.
If there's a way to do this, great; I'll have learned something today. If you feel that it is only possible by changing one of the problem constraints, we'll negotiate (IIUC it's only possible by changing the problem to make the total data received at least equal to the total data transmitted, by any of a variety of means).
think about what you are saying. If only a fraction of the currently restricted bandwith were so well utilized! As it is, you hear silence. Which is preferable? The possibility of a clog or enforced silence and frustration?
Clogging is a certainty without imposed limits; people are greedy that way. Removing band restrictions just guarantees that *all* parts of the spectrum are clogged.
Band restriction is a quality of service issue - if you want to be able to use your cell phone, or to put up an antenna and hear music from your favourite radio station, there must be a guarantee that the person next door isn't cluttering up that section of the spectrum for you. This is especially true for emergency services, and for bands that interfere with important equipment (radio beacons at airports come to mind).
What is it that you stand for?
Wired backbones. All the bandwidth you can eat, and much less contention for it. Limit wireless to short range, and put hubs everywhere. Problem solved (for urban areas; rural areas are an entirely different problem with different constraints).