Maybe you need a review of the basic principles of heat transfer.
If you set your oven to 150 degrees, how long would it take to cook a turkey? Your oven would cycle on and off, emitting energy into the environment surrounding the turkey, for as long as you let it run. But it seems unlikely that the turkey would ever exceed 150 degrees, because it loses heat to the environment faster than it's absorbing heat from the oven's heating element.
Why do you think things work differently if you change the source of energy from "IR/hot air" to "microwave"? In your world is there special form of heat caused by microwaves that cannot be dissipated in the usual way?
And let's not even discuss the amount of energy you absorb from the sun. The meteorological definition of "sunshine" is irradiance of at least 120 W/m^2 -- how does your cell phone compare to that?
It's because of actual heating, just like your microwave. It's a well-understood effect -- hence microwave ovens -- and it only happens if you absorb the relevant wavelength and the power level is sufficiently high.
I think you should compare "all of the shit we got blasting us with radiation everyday" with the amount of radiation the sun and the rest of the universe has blasted at you and your ancestors over the years.
But the iPad isn't a computer. Apple makes computers, and provides specs, dev tools, and all manner of "tinkering" opportunities. If you want an Apple computer, buy an Apple computer and stop whining about their appliances.
What a lame argument. Your microwave isn't locked because it's dangerous to tinker -- it's really not very dangerous even if you physically disassembled it -- it's locked because it's an appliance.
Having three teams code three versions does not solve (important) logic bugs, and while it's been tried in the past it's actual not a common approach anymore because it doesn't provide much (if any) reliability improvement and it's expensive.
While independent teams are unlikely to produce the same random errors -- typos, etc. -- the "hard" part of the program logic are hard for all three teams, and they're all likely to make mistakes in those same difficult areas. Often the same sorts of mistakes. This is particularly true if "hard" and "poorly specified" coincide, which is not at all uncommon.
The microwave on your kitchen counter started out as a magnetron in a lab that someone was tinkering with. Eventually it was packaged into a home appliance, and now tinkering is more or less impossible. Most people would consider this a good thing.
Why then, when the same thing happens to computers, do people proclaim it to be a bad thing? Isn't there space in the market for both appliance-like and general-purpose computers, just as there is space in the market for both microwave ovens and raw magnetrons?
This argument might make sense in a market where it is impossible to tinker -- like cell phones -- but in a market where the vast majority of machines are general-purpose hardware that can be used for any purpose it is simply nostalgic whining from a generation who still sees computers as the one great new technology that will equalize all of humanity.
I can certainly understand and support the idea that users should be allowed to do whatever they want with their general purpose computer. But it's absurd to suggest that Apple has to make that machine. At best the argument is "they shouldn't do this because it's a slippery slope", but even that seems a bit of a stretch given the current state of the market.
Now if you wanted to make this argument in a market where locked-down was the only option -- like cell phones or DVD players -- I might have more sympathy. But this particular instance just makes the whole movement look whiny.
Your microwave oven doesn't allow any third-party software to be run, has no data interface ports, and in general is quite difficult to modify even though it's controlled by generic, programmable digital electronics. But that's exactly how most people want it. There are certainly some users who would like to be able to reprogram their microwave, but the vast majority of users prefer the completely locked-down version they currently have.
Why should computers be any different? Yes, it is physically capable of running other programs. And I count myself among those who would actually run other programs on such a device, if given the opportunity. But we aren't (or at least shouldn't be) in the market for an iPad, or any similarly-restricted device. Just as the electronics market supports the sale of both general-purpose magnetrons on purpose-built microwave oven the computer market can support both general-purpose and purpose-built workstations.
You can correct perspective with a shift lens -- that is, you can keep parallel lines from converging. But it doesn't change the angle of observation; since the camera is still not in-line with a person's face they still won't be looking into the captured image.
If you're using keep-alive at the HTTP layer you're most certainly not closing and re-opening the underlying SSL socket -- in typical implementations the HTTP code is only vaguely aware that SSL even exists.
Now not every server or client supports or uses keep-alive. But if you do then SSL is only negotiated once per session, not once per HTTP request.
The article is imprecise, but HTTPS is higher latency, even when network and CPU capacity are sufficient -- setting up an SSL connection requires several more round trips than raw HTTP, so if your latency is higher than 0 it can be noticeably slower to use encrypted connections.
Encrypted connections also typically have some per-datagram overhead, though that's typically pretty small, and not strictly necessarily on streams if you're willing to give up integrity checks. And there is a CPU load. The CPU factor was mostly relevant 15 years ago, but on low-end systems (phones, for example) it can still be a problem. And on systems with high numbers of connections (servers, for example) it's not necessarily a problem bit it does require more horsepower.
No, the bandwidth needed is really quite high, because the signaling system is really inefficient. You could send a lot more data over the same radio link if it was encoded more efficiently.
The problem is they don't want to give up their old reliable voice comm system. That's probably a reasonable choice. But that choice eats a non-trivial portion of the bandwidth available for other communications systems.
Well they can simply turn GPS off (entirely or over certain areas) or introduce large-scale errors; since they don't control Galileo that's not an option and jamming is the only solution. And since jamming is not a precision tool it would be nice if jamming operations didn't interfere with the more selective control available for GPS.
They're probably also worried about unintentional interference from Galileo. Or jamming from third parties -- if someone starts jamming radionav systems it would be useful to know if they're targeting the EU or the US.
The airport system is LAAS. WAAS is a general-purpose accuracy improvement system with signals broadcast from geosynchronous satellites. WAAS provides a 95% probability of 25-foot or better accuracy both vertically and laterally (with real-world measurements closer to 5-feet) for any compatible receiver over almost all of North America. It also provides an integrity guard; GPS signals that are out-of-spec can be invalidated in under 10 seconds.
LAAS uses a local VHF link to provide additional accuracy within ~25 miles of a LAAS ground station. It's similar in function to WAAS but uses ground stations exclusively, and is intended primarily for use in aircraft navigation in cat II and cat III approaches.
That would be my guess, yes. Though they could allow Google to call them directly via the Internet and avoid the PSTN if they'd rather get the calls than lose the potential income.
$20/year really isn't possible, because no matter how low their internal operating costs, they have to terminate calls on the PSTN, and they don't have equipment in every city to do that on their own network. Legally mandated termination fees for rural areas can be $0.04/minute (or sometimes even higher) -- at that rate you'd only be able to talk for 500 minutes before they'd be in debt.
My guess they're taking advantage of these same fees, and giving everyone inbound phone numbers in high-termination-fee locations. So they collect $0.04/minute every time someone calls you, but for most outbound calls they only pay the much lower termination fees for metropolitan areas. It's the same sort of scam we've seen from companies offering free teleconferencing, or free international calling. It's probably not illegal under current laws, but it's also not the sort of thing that's sustainable long-term, because real phone companies aren't going to put up with paying for MagicJack's phone service.
AES-256 uses a 256-bit key. It has a fixed block size of 128 bits, but that's unrelated to the key length.
There is a related-key weakness in AES-256 and AES-192, bringing their effective strength down to 2^119 and 2^176 respectively. So AES-192 is your best bet right now, though 2^119 or 2^128 are not exactly feasible attack keyspaces either.
Radiation in general isn't the problem. There's some evidence that millimeter wave radiation in particular can un-zip DNA, even at its low energy, due to resonant effects.
Now it's not yet clear *how* damaging regular exposure to a millimeter wave scan would be -- millimeter waves already exist in the natural environment and haven't killed us all yet -- so it's entirely possible that there is no real danger. But I'd like to see some of the billions spent on these machines used to verify that before we get too far along.
You actually can't do rotary dialing on all lines -- I'm aware of a phone company in Iowa who actually hunted down their last pulse dialing user and gave them a new phone so they could turn off their old equipment.
And I really don't think you want the Internet to be run like the phone system -- limited to the technology we could imagine 50+ years ago for the sake of "backwards compatibility".
I guess you've never had to connect LANs from two different companies via a VPN. If you're both using the same RFC1918 address space it is incredibly difficult to route traffic around in any sensible fashion. If you want to talk about broken, non-sensical practices I'd start with that, which is squarely in the realm of what you suggest.
Even if every host doesn't need a public address (I think almost all hosts could use one, but I'm not going to argue that point here) there's still *exceptional* value in having a unified addressing plan so that you can coordinate easily with networks outside your immediate control. Just like there's value in have DIDs for every phone, as opposed to a single switchboard number and unpredictably-routed internal phone extensions, there's value in having unified addressing for every Internet host.
Is there some reason your Aunt Myrtle couldn't install the non-NAT, stateful firewall/modem that her ISP provides, as opposed to the NAT-enabled version of the same product? Does the non-NAT version have more wires or something?
Whatever box she's currently using to provide NAT could just as easily provide a pre-configured firewall without NAT. Virtually every member of the helpless masses you claim to be protecting with NAT are doing nothing to modify the box provided by their ISP/picked up at Best Buy.
The default config on that box could provide the option to turn the firewall and NAT on and off separately, and could give big scary warnings if you tried to disable the firewall. It could even ship with NAT off by default, assuming the ISP supported multiple IP addresses per account, so that end-users weren't burdened with the hassles of NAT unless they actually needed it.
Heck, with a minor bit of traffic monitoring you could have the firewall/NAT box automatically detect when there were unanswered DHCP queries, stop forwarding them, enable NAT, and answer future DHCP queries internally -- then users who needed NAT would get it with zero config and users with a single machine or access to multiple addresses could get real connections.
You do know that the smart engineers use the gullible ones as fodder to soak up annoying LibA students like you, right? I'd guess you never got in far enough to meet a real engineer, let alone try to sell him something.
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Maybe you need a review of the basic principles of heat transfer.
If you set your oven to 150 degrees, how long would it take to cook a turkey? Your oven would cycle on and off, emitting energy into the environment surrounding the turkey, for as long as you let it run. But it seems unlikely that the turkey would ever exceed 150 degrees, because it loses heat to the environment faster than it's absorbing heat from the oven's heating element.
Why do you think things work differently if you change the source of energy from "IR/hot air" to "microwave"? In your world is there special form of heat caused by microwaves that cannot be dissipated in the usual way?
And let's not even discuss the amount of energy you absorb from the sun. The meteorological definition of "sunshine" is irradiance of at least 120 W/m^2 -- how does your cell phone compare to that?
It's because of actual heating, just like your microwave. It's a well-understood effect -- hence microwave ovens -- and it only happens if you absorb the relevant wavelength and the power level is sufficiently high.
I think you should compare "all of the shit we got blasting us with radiation everyday" with the amount of radiation the sun and the rest of the universe has blasted at you and your ancestors over the years.
Sat phone is no where near that price. Even the "overage" minutes are only $1/minute, and plan minutes are quite a bit cheaper.
http://www.globalstarusa.com/en/airtime/voicepricing/
But the iPad isn't a computer. Apple makes computers, and provides specs, dev tools, and all manner of "tinkering" opportunities. If you want an Apple computer, buy an Apple computer and stop whining about their appliances.
What a lame argument. Your microwave isn't locked because it's dangerous to tinker -- it's really not very dangerous even if you physically disassembled it -- it's locked because it's an appliance.
Having three teams code three versions does not solve (important) logic bugs, and while it's been tried in the past it's actual not a common approach anymore because it doesn't provide much (if any) reliability improvement and it's expensive.
While independent teams are unlikely to produce the same random errors -- typos, etc. -- the "hard" part of the program logic are hard for all three teams, and they're all likely to make mistakes in those same difficult areas. Often the same sorts of mistakes. This is particularly true if "hard" and "poorly specified" coincide, which is not at all uncommon.
The microwave on your kitchen counter started out as a magnetron in a lab that someone was tinkering with. Eventually it was packaged into a home appliance, and now tinkering is more or less impossible. Most people would consider this a good thing.
Why then, when the same thing happens to computers, do people proclaim it to be a bad thing? Isn't there space in the market for both appliance-like and general-purpose computers, just as there is space in the market for both microwave ovens and raw magnetrons?
This argument might make sense in a market where it is impossible to tinker -- like cell phones -- but in a market where the vast majority of machines are general-purpose hardware that can be used for any purpose it is simply nostalgic whining from a generation who still sees computers as the one great new technology that will equalize all of humanity.
I can certainly understand and support the idea that users should be allowed to do whatever they want with their general purpose computer. But it's absurd to suggest that Apple has to make that machine. At best the argument is "they shouldn't do this because it's a slippery slope", but even that seems a bit of a stretch given the current state of the market.
Now if you wanted to make this argument in a market where locked-down was the only option -- like cell phones or DVD players -- I might have more sympathy. But this particular instance just makes the whole movement look whiny.
Your microwave oven doesn't allow any third-party software to be run, has no data interface ports, and in general is quite difficult to modify even though it's controlled by generic, programmable digital electronics. But that's exactly how most people want it. There are certainly some users who would like to be able to reprogram their microwave, but the vast majority of users prefer the completely locked-down version they currently have.
Why should computers be any different? Yes, it is physically capable of running other programs. And I count myself among those who would actually run other programs on such a device, if given the opportunity. But we aren't (or at least shouldn't be) in the market for an iPad, or any similarly-restricted device. Just as the electronics market supports the sale of both general-purpose magnetrons on purpose-built microwave oven the computer market can support both general-purpose and purpose-built workstations.
You can correct perspective with a shift lens -- that is, you can keep parallel lines from converging. But it doesn't change the angle of observation; since the camera is still not in-line with a person's face they still won't be looking into the captured image.
If you're using keep-alive at the HTTP layer you're most certainly not closing and re-opening the underlying SSL socket -- in typical implementations the HTTP code is only vaguely aware that SSL even exists.
Now not every server or client supports or uses keep-alive. But if you do then SSL is only negotiated once per session, not once per HTTP request.
The article is imprecise, but HTTPS is higher latency, even when network and CPU capacity are sufficient -- setting up an SSL connection requires several more round trips than raw HTTP, so if your latency is higher than 0 it can be noticeably slower to use encrypted connections.
Encrypted connections also typically have some per-datagram overhead, though that's typically pretty small, and not strictly necessarily on streams if you're willing to give up integrity checks. And there is a CPU load. The CPU factor was mostly relevant 15 years ago, but on low-end systems (phones, for example) it can still be a problem. And on systems with high numbers of connections (servers, for example) it's not necessarily a problem bit it does require more horsepower.
No, the bandwidth needed is really quite high, because the signaling system is really inefficient. You could send a lot more data over the same radio link if it was encoded more efficiently.
The problem is they don't want to give up their old reliable voice comm system. That's probably a reasonable choice. But that choice eats a non-trivial portion of the bandwidth available for other communications systems.
Well they can simply turn GPS off (entirely or over certain areas) or introduce large-scale errors; since they don't control Galileo that's not an option and jamming is the only solution. And since jamming is not a precision tool it would be nice if jamming operations didn't interfere with the more selective control available for GPS.
They're probably also worried about unintentional interference from Galileo. Or jamming from third parties -- if someone starts jamming radionav systems it would be useful to know if they're targeting the EU or the US.
The airport system is LAAS. WAAS is a general-purpose accuracy improvement system with signals broadcast from geosynchronous satellites. WAAS provides a 95% probability of 25-foot or better accuracy both vertically and laterally (with real-world measurements closer to 5-feet) for any compatible receiver over almost all of North America. It also provides an integrity guard; GPS signals that are out-of-spec can be invalidated in under 10 seconds.
LAAS uses a local VHF link to provide additional accuracy within ~25 miles of a LAAS ground station. It's similar in function to WAAS but uses ground stations exclusively, and is intended primarily for use in aircraft navigation in cat II and cat III approaches.
http://www.defense.gov/releases/release.aspx?releaseid=11335
That would be my guess, yes. Though they could allow Google to call them directly via the Internet and avoid the PSTN if they'd rather get the calls than lose the potential income.
Because modern *nix systems don't have process limits? Because a fork-bomb persists through a reboot?
That sort of setup would do nothing to influence the statistics quoted -- there would be one open and one not-open AP added to the count.
$20/year really isn't possible, because no matter how low their internal operating costs, they have to terminate calls on the PSTN, and they don't have equipment in every city to do that on their own network. Legally mandated termination fees for rural areas can be $0.04/minute (or sometimes even higher) -- at that rate you'd only be able to talk for 500 minutes before they'd be in debt.
My guess they're taking advantage of these same fees, and giving everyone inbound phone numbers in high-termination-fee locations. So they collect $0.04/minute every time someone calls you, but for most outbound calls they only pay the much lower termination fees for metropolitan areas. It's the same sort of scam we've seen from companies offering free teleconferencing, or free international calling. It's probably not illegal under current laws, but it's also not the sort of thing that's sustainable long-term, because real phone companies aren't going to put up with paying for MagicJack's phone service.
It's not a hardware license, it's a usage license -- cell carriers have exclusive licenses for the use of the spectrum.
AES-256 uses a 256-bit key. It has a fixed block size of 128 bits, but that's unrelated to the key length.
There is a related-key weakness in AES-256 and AES-192, bringing their effective strength down to 2^119 and 2^176 respectively. So AES-192 is your best bet right now, though 2^119 or 2^128 are not exactly feasible attack keyspaces either.
Radiation in general isn't the problem. There's some evidence that millimeter wave radiation in particular can un-zip DNA, even at its low energy, due to resonant effects.
http://www.technologyreview.com/blog/arxiv/24331/
Now it's not yet clear *how* damaging regular exposure to a millimeter wave scan would be -- millimeter waves already exist in the natural environment and haven't killed us all yet -- so it's entirely possible that there is no real danger. But I'd like to see some of the billions spent on these machines used to verify that before we get too far along.
You actually can't do rotary dialing on all lines -- I'm aware of a phone company in Iowa who actually hunted down their last pulse dialing user and gave them a new phone so they could turn off their old equipment.
And I really don't think you want the Internet to be run like the phone system -- limited to the technology we could imagine 50+ years ago for the sake of "backwards compatibility".
I guess you've never had to connect LANs from two different companies via a VPN. If you're both using the same RFC1918 address space it is incredibly difficult to route traffic around in any sensible fashion. If you want to talk about broken, non-sensical practices I'd start with that, which is squarely in the realm of what you suggest.
Even if every host doesn't need a public address (I think almost all hosts could use one, but I'm not going to argue that point here) there's still *exceptional* value in having a unified addressing plan so that you can coordinate easily with networks outside your immediate control. Just like there's value in have DIDs for every phone, as opposed to a single switchboard number and unpredictably-routed internal phone extensions, there's value in having unified addressing for every Internet host.
Is there some reason your Aunt Myrtle couldn't install the non-NAT, stateful firewall/modem that her ISP provides, as opposed to the NAT-enabled version of the same product? Does the non-NAT version have more wires or something?
Whatever box she's currently using to provide NAT could just as easily provide a pre-configured firewall without NAT. Virtually every member of the helpless masses you claim to be protecting with NAT are doing nothing to modify the box provided by their ISP/picked up at Best Buy.
The default config on that box could provide the option to turn the firewall and NAT on and off separately, and could give big scary warnings if you tried to disable the firewall. It could even ship with NAT off by default, assuming the ISP supported multiple IP addresses per account, so that end-users weren't burdened with the hassles of NAT unless they actually needed it.
Heck, with a minor bit of traffic monitoring you could have the firewall/NAT box automatically detect when there were unanswered DHCP queries, stop forwarding them, enable NAT, and answer future DHCP queries internally -- then users who needed NAT would get it with zero config and users with a single machine or access to multiple addresses could get real connections.
You do know that the smart engineers use the gullible ones as fodder to soak up annoying LibA students like you, right? I'd guess you never got in far enough to meet a real engineer, let alone try to sell him something.