So, along with the URL you imbed in this barcode, you also imbed a unique ID.
This would require custom printing work, perhaps laser printing, on every issue of the magazine (and making certain that all the pages with the same copy ID number come together during the printing and binding process). This is a lot more expensive than offset printing, and the publisher would have to find some way of getting that money back. After processing the thousands of dropped subscriptions from former readers who'd been billed extra after lending the issue to a friend or leaving it in the bathroom when company came over, they'd learn their lesson. -- This post made from 100% post-consumer recycled magnetic
Maybe you'll scan the bar-codes with the scanner stylus of your Palm IXp, and scan the referenced stuff via GSM modem. If you think it's worthwhile, you'll bookmark it, otherwise you'll dump it. -- This post made from 100% post-consumer recycled magnetic
Flamebait? Lots of anti-Katz prejudice among today's crop of moderators. A condescending or sarcastic response to a personal attack isn't flamebait, guys. It's more in the league of "Here's a clue." -- This post made from 100% post-consumer recycled magnetic
I do not agree with ACLU stances on every issue, but what other organization is doing anything productive for my desire for online privacy and anonymity?
Try the Electronic Frontier Foundation, eff.org. -- This post made from 100% post-consumer recycled magnetic
You're surrounded by evidence that blatantly goes against your argument.
And you're absolutely right, until you log off the web and take your pick of the sanitized, corporatized viewpoints which are almost all that's available through TV, radio or print media. Jon is more familiar with those than you are, and he's got a point you should take seriously. -- This post made from 100% post-consumer recycled magnetic
Why is it that America has proven to be the ideal breeding ground for the current corporation-driven global economy that has gotten so out of hand?
Because America has its own flavor of culture and everything else, and you see it most keenly here because you're not familiar with the world and the various ways the same forces exhibit themselves in other milieus.
If you look at all of the major issues that come up on/. about 95% of them are birthed in the US.
Ever give thought to the fact that the people who post issues to/. have a rather seriously US-centric view and the weltanschauung concentrates on matters of concern to the on-line geek populace, which is very much dominated by young, techie, left and/or libertarian males from the USA? Think about sampling error sometime. Think about what ought to be obvious.
How did the nation which prides itself on its God-given rights to freedom come to end up in such a state?
Because it had to end up in some state. Look at all the states we didn't end up in. We didn't end up dominated by a totalitarian dictatorship, like the ex-USSR. We didn't end up locked in by huge corporate/government/financial behemoths, like the Japanese with their kieretsu or the S. Koreans with their chaibol (sp?). We didn't end up with an economy dominated by socialistic government, huge trade unions and equally large corporations deciding how the pie should be divided, like Europe. We wound up with something unique, and changing as we speak.
Did you have a point to make? -- This post made from 100% post-consumer recycled magnetic
Earth is 93 million miles from Sol; that's about 500 light-seconds. Jupiter, 5.2 AU or 2600 light-seconds; less than 45 minutes. Pluto is what, 40 AU more or less? 20,000 seconds, or about 5.5 light-hours. You'd have to be over 80 AU from Sol before your round-trip time reached a day. I remember when Usenet posts could easily take a day or more to propogate around the various servers; somehow, I don't think that the time delay would keep electronic culture from flowering across an enormous expanse of space. -- This post made from 100% post-consumer recycled magnetic
How well will the Internet scale when it extends to distant planets or even stars?
How are you going to handle a retry request from a site 4.3 light-years away?
TCP/IP essentially doesn't work over such distances. On the other hand, schemes like Fidonet and Usenet News would work fine as long as they had a transport scheme underneath. You can forget a System-Wide Web, but a system of caching servers for Usenet posts, static web pages, or any other kind of content that doesn't require active communication with the originator will work fine. All you have to do is broadcast everything that's new or changed, and use appropriate encoding to guarantee that the receiver can reconstruct any data errors (something like trellis encoding would be appropriate). What you'd get at Pluto would be some hours out of date and Alpha Centauri would be years behind the fashions, but it would get there. -- This post made from 100% post-consumer recycled magnetic
...you really have to wonder if this is a great idea. No matter how much security they put in, this makes either the satellite or their router vulnerable to a lot of the stuff people pull with TCP/IP these days.
There are basically 2 ways to talk to the spacecraft: through your own radio gear, or through whatever gateways and firewalls other people have put between the Internet and their radio gear.
If you have your own radio gear, you could have sent commands to the satellite using whatever protocol and authentication it wants even without TCP/IP. Adding TCP/IP, if the satellite functions are protected with the same authentication codes, doesn't make it significantly easier.
The other way is to hack through someone else's gateway. If they've firewalled it, you've got the problem of defeating the firewall before you get to the satellite and its authentication mechanisms. Of course, if someone has left the authentication info lying around in an accessible place on their Internet-accessible computer, you're all set... assuming the satellite will accept configuration commands over the TCP/IP channel (it might not, the article didn't say if this was only used for the store/forward system or command and control as well).
It's a pity we can't just ask Bruce Schnier for his opinion of their security model. -- This post made from 100% post-consumer recycled magnetic
just something so cool about sending packets into outerspace and getting a response
Space scientists would disagree with you on that point. This satellite is in low-earth orbit (LEO), which is not technically considered to be "outer space". If you uploaded a TCP/IP stack to one of the Voyager probes or even Galileo, that would certainly qualify. How many million msec is your timeout again? -- This post made from 100% post-consumer recycled magnetic
Exactly what loss could Microsoft claim if someone "lost" a stripped copy of the document?
Not that the document is useful, all it describes is a broken implementation of Kerberos that ought not to see the light of day. Maybe people who need M$ apps should stick with Win 98 on the desktop until WINE is good enough to run the latest version of Office, then kiss M$'s OS bye-bye. -- This post made from 100% post-consumer recycled magnetic
The big problem is stuff like the lead in the solder and in the glass faces of CRT's. So far as I know, recycling those isn't exactly common. -- This post made from 100% post-consumer recycled magnetic
In any case, this just gives you eavesdropping-proof communication channels.... it does nothing about the man-in-the-middle attack.
Man-in-the-middle is exactly what it's about.
The trick works by generating pairs of photons with coupled polarizations. Now here's the important point: if you measure the polarization of a photon at vertical or horizontal, it has no relationship to the measurement of the polarization at 45 degrees vs. 135 degrees. Alice generates pairs of photons and sends one photon to Bob. She generates a random string of 1's and 0's, uses this to select between a 0/90 degree polarizing filter and a 45/135 degree polarizing filter, and measures the polarization of the photons she does not send. Meanwhile, Bob performs a similar, random set of polarization tests at his end. After they are done, Alice tells Bob what sequence of polarizations she used for her tests. Bob throws out the measurements where he did not use the same axes as Alice, and the remaining measurements form a random bit pattern shared by Alice and Bob. Charlie sitting in the middle doesn't know what measurement to make (because Alice hasn't told anyone yet) and can't measure the photon without destroying its state. Charlie could measure the photon with a 0/90 degree filter, but if Alice is doing her measurement on that photon with a 45/135 degree filter then his measurement will have no relationship to her data. He can generate a photon with the corret polarization for the 0/90 degree test, but Bob is going to detect a different result from Alice with 50% probability. If Alice and Bob compare a subset of their bits (which they will not use for a key), they'll detect Charlie's tampering. Ergo, the man-in-the-middle attack doesn't work. Photon loss on fiber makes it impractical for networks, but there are other regimes where this idea just might shine. -- This post made from 100% post-consumer recycled magnetic
it will be possible to find how much of the matter in the universe is barionic
I've heard of baryons, but barions? I think it would be really great to know how much of the universe is bar-ions. This will be essential to the human settlement of the universe, because if you can't get a charge out of drinking in the tavern anywhere except on Earth, nobody will want to go! (Or the cosmos will be inherited by humorless teetotallers, which would be even worse.) -- This post made from 100% post-consumer recycled magnetic
Back in the days when people actually backed up on floppies, there was a company which had a pretty convincing demo of their software's recovery capabilities: they took a backup floppy, made a hole in it with a hole punch, and read all the data back regardless.
This isn't rocket science, and it wouldn't be all that difficult to do the same thing today. All you'd really need to do is to create a disk format that allows you to scatter file data across the floppy and reserve some fraction of the disk for parity or Hamming code sectors, which you use to reconstruct any sectors you lose. You'd have to be sophisticated about where you arrange your data (if you lose too much of the redundancy for any one part, your data is still toast) but this would allow you to manage things on a single floppy. Now that I think about it, it shouldn't be too hard to make a parity file which occupies certain tracks (say, the inner 8 tracks) and use the sectors on those tracks as parity for the other 72. With a little sophisticated software, you could recover any single lost sector or track. --
can't even slight amounts of scattering seriously distort the data being transmitted?
They'll attenuate it, but distortion isn't much of a factor. Visualize it this way: the transmitter emits a train of pulses, which travel at the speed of light. For the pulses to be distorted, something has to either block stronger or weaker parts preferentially (a non-linearity), or delay part of the pulse so that it starts interfering with the next pulse. For this to happen with light going through fog, a substantial part of the pulse would have to follow a longer path. This requires at least two (and possibly three) scattering events: one off the line of sight and one back toward the receiver (assuming the receiver is not highly directional and only taking signal directly from the transmitter, in which case you need a bounce back onto the line of sight and then a third bounce to send it to the receiver). As you can see just from hand-waving, the probability of a photon coming in with a delay is vastly smaller than it being lost. Thus, distortion isn't a big worry.
I'm rather curious about upload vs. download speeds.
That's going to depend on the exact technology used, and the tradeoffs chosen by the designers.
But mightn't minor tremors (in an area which, like much of California, is prone to seismic activity) inspire a need to perpetually realign the trasmitting and receiving gear?
Sure. If you need accurate pointing to an arc-minute, anything that jiggles the optics by that much or more is going to screw up your system. (This includes birds landing on it, squirrels climbing on it, the wind blowing it around...) On the other hand, the same technology which we use to make CD players which focus themselves and follow tracks wherever they waver ought to be able to make a self-aligning laser transceiver. If CD drive prices are any guide, they'll be cheap in quantity. --
Great scientific discoveries are inseparable from key changes in technology. Many of the elements in the periodic table were identified in the decade after the invention of the storage battery...
Given that, we are likely heading towards the Mother of all Periods of Scientific Discovery.
The conclusion does not follow. The storage battery enabled the study of electrochemistry (indeed, it was an electrochemical device itself). What kind of device is the Internet, that it enables scientific discovery? It allows sharing of results and thought, but it does absolutely nothing for the capabilities of the laboratory.
The Internet is already fostering a social revolution, but the scientific fallout is going to be a second- or third-order effect at most. --
What is the wave length of the light used in this laser?
I'll bet it's around 900-1000 nanometers, which is close enough to invisible. You won't see very much without an image intensifier. Now, as for your camcorder, el-cheapo low-light TV camera... those are another matter. --
As you go into the infrared, the influence of fog drops; once the wavelength of the light gets to be much larger than the droplet size, they stop scattering very effectively. If you use a larger lens (say, a fresnel lens instead of a small glass lens) the effect of blocking a small area diminishes. Besides, I'm sure your router is capable of handling the effects of a brief dropout in the signal, and that's all a bird is going to give you.
Free-space optical transmission has distinct advantages over radio and microwave, notably a lack of licensing restrictions and extremely high transmission rates. Would you put up with 2 Mbps when you could have 100 Mbps or more? Neither would I. If I ran an ISP in an area where fog was infrequent (say, from Los Angeles down to San Diego and east to Austin TX or so) this would be a great way to roll out digital services at speeds DSL cannot even dream of, while still being able to make money off a sparsely distributed subscriber population. This will drive the demand curve which will then make it possible to get fiber all the way to the service entrance. It's not the end-all, but it's a great foot in the door. --
...call me an EE major (I am one:-) but I belive infrared is ABOVE microwave in frequency.
Call me a double-E (I have a degree that says that I am). Infrared is indeed "above" (greater energy, shorter wavelength) microwave radiation. The clock signal does affect the radiation from a device; the faster the clock and the sharper the edges, the more RF radiation you get from the leads and such. This isn't going to cook you, but RFI and Tempest emissions ought to be kept in mind.
Cliff wrote:
Currently processors heat up because they emit infrared radiation, but what is going to happen when they start to emit -microwave- radiation?
Well, Cliff ol' boy, I've got news for you: processors don't heat up because they emit infrared radiation, they emit infrared radiation period. So do you. A square meter of blackbody radiator at skin temperature emits about 450 watts[1], mostly in the infrared. However, some of it is actually at longer wavelengths, down into the microwaves. (YOU are a MICROWAVE EMITTER! And if you don't pay me $10,000, I'll TELL YOUR FRIENDS AND FAMILY!)
This property is used all the time. One of the methods for sensing temperature remotely is with microwave radiometry; it's how the surface temperature of Venus was determined before probes were ever sent there, and the bulk temperature of Earth's atmosphere is measured by satellite sensors using that same technique to this very day.
You don't have to worry about microwave emissions from a CPU chip, even if it's running at a couple of GHz. The chip carrier itself usually has a metal plate for heat dissipation, forming a ground plane; ground planes provide "equal and opposite" mirror currents and mostly cancel the emissions. The metal lid is another ground plane. Even at 3 GHz, a wavelength is 10 centimeters; most traces on the chip are but a fraction of a millimeter long, and don't have the physical size to radiate well. What radiation they do emit will be cancelled by image currents in the ground planes and confined inside the chip carrier until it is absorbed by resistance in the silicon itself. The biggest issue is emissions from leads which go out of the chip itself, and those are usually running at a much lower frequency than the CPU core. What gets out is microwatts at most; this can be troublesome, but danger to people is way down on the list of concerns.
I think the summary is, no need to worry yet but you should probably do some reading so that you will know if and when you should worry in the future.
[1] Blackbody radiation flux is determined by the absolute temperature and Boltzmann's constant; the formula for the radiation per unit area is flux = 5.67*10^(-8) W/m^2/K^4 * temperature^4, so the heat flux increases as the fourth power of temperature. --
the/. community only ever gets exposed to those [patents] which are bad in their view. After all, it doesn't make much sense for Rob and co. to put a story up saying "Company X gets patent for invention they put time and money into", not when they want controversy in order to generate more ad revenue. In this sense,/. has become the Linux zealot's equivalent of the tabloids, which is a pity. Not true. Slashdot is a narrowly-focussed forum, devoted mostly to software. What's one area where the USPTO has just been forced to grant patents, and has neither a lot of expertise nor the body of prior art (usually defined as previously patented ideas) with which to judge applications? Software. It isn't at all wrong for Slashdot to be reacting to the rash of bad patents which come from this state of affairs, and the appropriate response is overwhelmingly negative. Which isn't to say that patents in other areas meet the standards either. There's a company which makes electronic compasses for cars which patented a location for the field sensor; nobody else is allowed to build a compass with the field sensor in an overhead console without paying them a royalty. This is so glaringly obvious to anyone who thinks about it for two seconds that there's no way it should have been granted a patent, but the USPTO did and at least one VERY large auto company refused to fight it. This does restrict innovation, and if I am asked to testify I will swear to it in court. --
Slashdot Mirror
--
This post made from 100% post-consumer recycled magnetic
Maybe you'll scan the bar-codes with the scanner stylus of your Palm IXp, and scan the referenced stuff via GSM modem. If you think it's worthwhile, you'll bookmark it, otherwise you'll dump it.
--
This post made from 100% post-consumer recycled magnetic
Flamebait? Lots of anti-Katz prejudice among today's crop of moderators. A condescending or sarcastic response to a personal attack isn't flamebait, guys. It's more in the league of "Here's a clue."
--
This post made from 100% post-consumer recycled magnetic
--
This post made from 100% post-consumer recycled magnetic
--
This post made from 100% post-consumer recycled magnetic
Did you have a point to make?
--
This post made from 100% post-consumer recycled magnetic
Earth is 93 million miles from Sol; that's about 500 light-seconds. Jupiter, 5.2 AU or 2600 light-seconds; less than 45 minutes. Pluto is what, 40 AU more or less? 20,000 seconds, or about 5.5 light-hours. You'd have to be over 80 AU from Sol before your round-trip time reached a day. I remember when Usenet posts could easily take a day or more to propogate around the various servers; somehow, I don't think that the time delay would keep electronic culture from flowering across an enormous expanse of space.
--
This post made from 100% post-consumer recycled magnetic
TCP/IP essentially doesn't work over such distances. On the other hand, schemes like Fidonet and Usenet News would work fine as long as they had a transport scheme underneath. You can forget a System-Wide Web, but a system of caching servers for Usenet posts, static web pages, or any other kind of content that doesn't require active communication with the originator will work fine. All you have to do is broadcast everything that's new or changed, and use appropriate encoding to guarantee that the receiver can reconstruct any data errors (something like trellis encoding would be appropriate). What you'd get at Pluto would be some hours out of date and Alpha Centauri would be years behind the fashions, but it would get there.
--
This post made from 100% post-consumer recycled magnetic
If you have your own radio gear, you could have sent commands to the satellite using whatever protocol and authentication it wants even without TCP/IP. Adding TCP/IP, if the satellite functions are protected with the same authentication codes, doesn't make it significantly easier.
The other way is to hack through someone else's gateway. If they've firewalled it, you've got the problem of defeating the firewall before you get to the satellite and its authentication mechanisms. Of course, if someone has left the authentication info lying around in an accessible place on their Internet-accessible computer, you're all set... assuming the satellite will accept configuration commands over the TCP/IP channel (it might not, the article didn't say if this was only used for the store/forward system or command and control as well).
It's a pity we can't just ask Bruce Schnier for his opinion of their security model.
--
This post made from 100% post-consumer recycled magnetic
--
This post made from 100% post-consumer recycled magnetic
Not that the document is useful, all it describes is a broken implementation of Kerberos that ought not to see the light of day. Maybe people who need M$ apps should stick with Win 98 on the desktop until WINE is good enough to run the latest version of Office, then kiss M$'s OS bye-bye.
--
This post made from 100% post-consumer recycled magnetic
The big problem is stuff like the lead in the solder and in the glass faces of CRT's. So far as I know, recycling those isn't exactly common.
--
This post made from 100% post-consumer recycled magnetic
Just login as slashdoted/slashdot, and nuke your cookie after the session.
--
This post made from 100% post-consumer recycled magnetic
The trick works by generating pairs of photons with coupled polarizations. Now here's the important point: if you measure the polarization of a photon at vertical or horizontal, it has no relationship to the measurement of the polarization at 45 degrees vs. 135 degrees. Alice generates pairs of photons and sends one photon to Bob. She generates a random string of 1's and 0's, uses this to select between a 0/90 degree polarizing filter and a 45/135 degree polarizing filter, and measures the polarization of the photons she does not send. Meanwhile, Bob performs a similar, random set of polarization tests at his end. After they are done, Alice tells Bob what sequence of polarizations she used for her tests. Bob throws out the measurements where he did not use the same axes as Alice, and the remaining measurements form a random bit pattern shared by Alice and Bob. Charlie sitting in the middle doesn't know what measurement to make (because Alice hasn't told anyone yet) and can't measure the photon without destroying its state. Charlie could measure the photon with a 0/90 degree filter, but if Alice is doing her measurement on that photon with a 45/135 degree filter then his measurement will have no relationship to her data. He can generate a photon with the corret polarization for the 0/90 degree test, but Bob is going to detect a different result from Alice with 50% probability. If Alice and Bob compare a subset of their bits (which they will not use for a key), they'll detect Charlie's tampering. Ergo, the man-in-the-middle attack doesn't work. Photon loss on fiber makes it impractical for networks, but there are other regimes where this idea just might shine.
--
This post made from 100% post-consumer recycled magnetic
--
This post made from 100% post-consumer recycled magnetic
This isn't rocket science, and it wouldn't be all that difficult to do the same thing today. All you'd really need to do is to create a disk format that allows you to scatter file data across the floppy and reserve some fraction of the disk for parity or Hamming code sectors, which you use to reconstruct any sectors you lose. You'd have to be sophisticated about where you arrange your data (if you lose too much of the redundancy for any one part, your data is still toast) but this would allow you to manage things on a single floppy. Now that I think about it, it shouldn't be too hard to make a parity file which occupies certain tracks (say, the inner 8 tracks) and use the sectors on those tracks as parity for the other 72. With a little sophisticated software, you could recover any single lost sector or track.
--
--
The Internet is already fostering a social revolution, but the scientific fallout is going to be a second- or third-order effect at most.
--
--
Free-space optical transmission has distinct advantages over radio and microwave, notably a lack of licensing restrictions and extremely high transmission rates. Would you put up with 2 Mbps when you could have 100 Mbps or more? Neither would I. If I ran an ISP in an area where fog was infrequent (say, from Los Angeles down to San Diego and east to Austin TX or so) this would be a great way to roll out digital services at speeds DSL cannot even dream of, while still being able to make money off a sparsely distributed subscriber population. This will drive the demand curve which will then make it possible to get fiber all the way to the service entrance. It's not the end-all, but it's a great foot in the door.
--
Cliff wrote:
Well, Cliff ol' boy, I've got news for you: processors don't heat up because they emit infrared radiation, they emit infrared radiation period. So do you. A square meter of blackbody radiator at skin temperature emits about 450 watts[1], mostly in the infrared. However, some of it is actually at longer wavelengths, down into the microwaves. (YOU are a MICROWAVE EMITTER! And if you don't pay me $10,000, I'll TELL YOUR FRIENDS AND FAMILY!)This property is used all the time. One of the methods for sensing temperature remotely is with microwave radiometry; it's how the surface temperature of Venus was determined before probes were ever sent there, and the bulk temperature of Earth's atmosphere is measured by satellite sensors using that same technique to this very day.
You don't have to worry about microwave emissions from a CPU chip, even if it's running at a couple of GHz. The chip carrier itself usually has a metal plate for heat dissipation, forming a ground plane; ground planes provide "equal and opposite" mirror currents and mostly cancel the emissions. The metal lid is another ground plane. Even at 3 GHz, a wavelength is 10 centimeters; most traces on the chip are but a fraction of a millimeter long, and don't have the physical size to radiate well. What radiation they do emit will be cancelled by image currents in the ground planes and confined inside the chip carrier until it is absorbed by resistance in the silicon itself. The biggest issue is emissions from leads which go out of the chip itself, and those are usually running at a much lower frequency than the CPU core. What gets out is microwatts at most; this can be troublesome, but danger to people is way down on the list of concerns.
I think the summary is, no need to worry yet but you should probably do some reading so that you will know if and when you should worry in the future.
[1] Blackbody radiation flux is determined by the absolute temperature and Boltzmann's constant; the formula for the radiation per unit area is flux = 5.67*10^(-8) W/m^2/K^4 * temperature^4, so the heat flux increases as the fourth power of temperature.
--
Michael Feldman of "What do you know" makes cracks about Alan Greenspan pretty regularly during his "all the news that isn't" monologue.
--
Sorry about the formatting, folks; something seems to have ignored the blockquote tags.
--
You've just described compulsory licensing.
--
the /. community only ever gets exposed to those [patents] which are bad in their view. After all, it doesn't make much sense for Rob and co. to put a story up saying "Company X gets patent for invention they put time and money into", not when they want controversy in order to generate more ad revenue. In this sense, /. has become the Linux zealot's equivalent of the tabloids, which is a pity. Not true. Slashdot is a narrowly-focussed forum, devoted mostly to software. What's one area where the USPTO has just been forced to grant patents, and has neither a lot of expertise nor the body of prior art (usually defined as previously patented ideas) with which to judge applications? Software. It isn't at all wrong for Slashdot to be reacting to the rash of bad patents which come from this state of affairs, and the appropriate response is overwhelmingly negative. Which isn't to say that patents in other areas meet the standards either. There's a company which makes electronic compasses for cars which patented a location for the field sensor; nobody else is allowed to build a compass with the field sensor in an overhead console without paying them a royalty. This is so glaringly obvious to anyone who thinks about it for two seconds that there's no way it should have been granted a patent, but the USPTO did and at least one VERY large auto company refused to fight it. This does restrict innovation, and if I am asked to testify I will swear to it in court.
--