Really when you think about it, Biometrics basically halts any kind of Social Engineering. You can't get around them without chopping off someone's hand and plucking out their eyes,
So, you're saying if I socially engineer the password to the database where the biometric data is stored and I use the password to swap the records on a known rapist and my victim, that this will fail because????
At the end of the day, biometric data may or may not be unforgeable, but it's the relationship to other data that is important. And that's hackable.
a) the vehicle may blind by reflected light at a considerable distance (100m - 1km or more- think of the wildlife [handwring]).
b) it ideally uses pure liquid hydrogen fuel; this means that the fuel tank ends up pretty heavy relative to the fuel (heavier than the space shuttle, because the Space Shuttle tank also holds LOX, so the average propellent density is rather better.) The ratio of the vehicle weight full/empty is critical in a high performing rocket- so this rocket doesn't perform as well as you would hope- it's not a SSTO solution, not quite, so he has a drop tank or two.
c) got a few billion? The lasers are very expensive... note that conventional rockets can be designed for *well* under a billion if you don't do anything fancy (see SpaceX)
d) it works best when you are launching a lot, but then again, just about any launch system gets cheap real fast if you launch a lot; and this one is expensive up front, so you have to launch even more to offset this.
Still, it's a very cool idea, and he's still working on it. But I can't shake the feeling Jordin has missed something that will move the idea up one more notch.
Nah. The astronauts were intact when they hit the water (probably unconscious, possibly dead), but intact, and yet this mythical, nonexistent plutonium (in a sturdy shielded capsule) would have miraculously disintegrated and somehow, magically covered the whole of florida? Sorry. Ain't gonna happen.
just ONE driver makes an error... then all hell breaks loose.
That's just one butterfly though. It's the jam spreading out from there that causes the problems.
Both are fundamentally chaotic.
Yes, but the principle of chaos is that small changes to the initial conditions lead to an exponentially divergent change to the result.
So, the earlier you are able to detect a single car crash, or the traffic jam around it, the quicker you will be able predict a city-wide gridlock- and perhaps arrange for your own butterfly to manage the problem perhaps you change some traffic lights so as to prevent gridlock entirely.
I think the problem might be if you have a window open- like a banking site up, or ebay, amazon etc. etc., and you open another website; or somebody sends you spam with html attachment or something.
As soon as it gets executed javascript replaces the real page with a fake one. If you don't notice the switch then the 'fun' ensues as you try to 'log back in'.
Sure it is a big target but it is 36,000 km up and not that many countries have the capability to shoot it down
Quite a lot do though- and they are all potential targets as well; really rather motivated to take it out. And any such a *weapon* is even a threat to the country that built it if terrorists or another enemy got hold of the controls.
Next we come to defence. Sure you can use tin foil but you would be looking funny.
Oh well, if you'd *look* funny, you'd have to die then.:-)
And you would need to wear it all the time since the beam can be swept in within seconds to any place visible from the SPS.
Only if they could build it. They couldn't, because another country would blast it to pieces before it was finished.
even less so when you can smoke the launch facilities of anyone threatening you.
No. Which bit of 'easy to defend' didn't you understand? If the long words confused you, you only have to ask.
The beam power might be 9 GW, but the energy density would be about the same as a cell phone gives out. The idea is that you create a big aerial called a rectenna that covers whole square kilometers and collect the dilute energy.
The problem is that in order to beam the microwaves down from geosynchronous orbit a huge antenna is needed to focus it down to even cell phone power density.
There's only two ways to up the power intensity in the beam:
a) build a bigger antenna in space (people would notice)
b) increase the power in the antenna (needs much bigger solar panels- people would notice)
Basically either way involves incredibly large amounts of money, and the weapon can't move so is easy to shoot at, easy to defend against (silver foil) and obvious.
Power. It takes an incredibly large amount of power to climb 38000 km to geosynchronous orbit.
It's ~500 KW per tonne of elevator to go at 200km/h near to the ground, but weight gradually reduces as you get nearer to geosynchronous orbit, and away from the earth and the power scales down proportionately.
The problem is, you can't carry enough fuel to get to the top (unless you use nuclear, but that's heavy).
Brad Edwards plan involves using ground based lasers to power photovoltaic panels.
You aren't fining them for being infected, you are charging them for fixing their PC. That's quite different; it costs manpower, whereas simply fixing a bit to let them back onto your network- that costs far, far less. Why should anyone be charged, or pay, >$35 for that?
Also, that's viruses you're talking about- what about worms?
Maybe some sort of "reconnection fee" from the ISP in the $35-50 range would be a good enough speedbump to make consumers aware that this kind of threat exists and it will be their problem if they don't protect themselves from it.
Probably a baddddd idea.
The issue is that, in practice, a vast number of boxes on the internet are all vulnerable to attack- there's bound to be some hidden flaw in the incredible number of packages out there.
So the system can be up-to-date with all known patches, and still be attacked. Fining people for things that flat-out aren't their fault is likely to be, at best, contrary to the ISPs customers idea about what makes a good ISP.
I think the wing is more critical- as I understand it Space Ship One/the pilot will not survive without the wing pivoting. If the undercarriage fails he still stands some kind of chance.
If you leave the atmosphere tumbling out of control, you'll hit it out of control and you'll be far less likely to ever regain it. Indeed, at that air speed, as you drop you into thicker air out of control you are far more likely to suffer complete structural failure.
Actually- that's less of a problem for this vehicle than other ones. The reason the wing folds up and back is that in that position the vehicle is self stabilising- so during reentry Space Ship One will naturally take up an appropriate attitude.
Of course, if the wing doesn't fold up at the right time- you're in for a bad day. AFAIK it's a safety critical item with no backup.
It is hard to write one with good locality of reference. That means that an object is closely placed in memory to an object that it references, even if it is a different type.
If you don't do that you tend to thrash your processor's cache. And that's slow.
At the end of the day, you use the right tool for the job; I hsve heard of people doing bigger realtime jobs than that using LISP (they partially switched off the GC in that case).
But, because they used LISP, they had a competitive advantage- they could easily add complicated features- and were laughing all the way to the bank.
With a custom allocator you often know the size of object you are allocating and sometimes the order in which those objects will be referenced, you can pre-allocate a chunk of memory of n * 'size' and hand out consecutive 'size' chunks when memory is needed.
Sounds like a heck of a lot of fiddling about to me; and brittle code; change the sizes of the objects or allocate an extra object anywhere and suddenly your custom allocator runs like dog food.
I suppose it does depend on how you write the allocator, but it's still not sounding great to me; and if objects get deleted- you're looking at the potential for a *lot* of unused space.
That's the point about GC- it does pretty well most or all of the time.
Um. Both memory arenas and customer allocators are likely to make locality worse... the whole point about garbage collectors is that they compress the objects down and hence improve locality.
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I got 200 miles at 5000 ft. There are big problems with the link budget at those distances however.
You can vary the wavelength across the array, and that avoids most of the problems with speckle patterns.
So, you're saying if I socially engineer the password to the database where the biometric data is stored and I use the password to swap the records on a known rapist and my victim, that this will fail because????
At the end of the day, biometric data may or may not be unforgeable, but it's the relationship to other data that is important. And that's hackable.
A laser propelled solar sail? Yeah, that's been proposed. It works.
Nope. 709k Final report pdf there too.
I'm worried there's been a DNS attack or something, and it's being faked just a little too well.
a) the vehicle may blind by reflected light at a considerable distance (100m - 1km or more- think of the wildlife [handwring]).
b) it ideally uses pure liquid hydrogen fuel; this means that the fuel tank ends up pretty heavy relative to the fuel (heavier than the space shuttle, because the Space Shuttle tank also holds LOX, so the average propellent density is rather better.) The ratio of the vehicle weight full/empty is critical in a high performing rocket- so this rocket doesn't perform as well as you would hope- it's not a SSTO solution, not quite, so he has a drop tank or two.
c) got a few billion? The lasers are very expensive... note that conventional rockets can be designed for *well* under a billion if you don't do anything fancy (see SpaceX)
d) it works best when you are launching a lot, but then again, just about any launch system gets cheap real fast if you launch a lot; and this one is expensive up front, so you have to launch even more to offset this.
Still, it's a very cool idea, and he's still working on it. But I can't shake the feeling Jordin has missed something that will move the idea up one more notch.
Nah. The astronauts were intact when they hit the water (probably unconscious, possibly dead), but intact, and yet this mythical, nonexistent plutonium (in a sturdy shielded capsule) would have miraculously disintegrated and somehow, magically covered the whole of florida? Sorry. Ain't gonna happen.
That's just one butterfly though. It's the jam spreading out from there that causes the problems.
Both are fundamentally chaotic.
Yes, but the principle of chaos is that small changes to the initial conditions lead to an exponentially divergent change to the result.
So, the earlier you are able to detect a single car crash, or the traffic jam around it, the quicker you will be able predict a city-wide gridlock- and perhaps arrange for your own butterfly to manage the problem perhaps you change some traffic lights so as to prevent gridlock entirely.
People are just flat out unpredictable.
So are air molecules.
As soon as it gets executed javascript replaces the real page with a fake one. If you don't notice the switch then the 'fun' ensues as you try to 'log back in'.
Quite a lot do though- and they are all potential targets as well; really rather motivated to take it out. And any such a *weapon* is even a threat to the country that built it if terrorists or another enemy got hold of the controls.
Next we come to defence. Sure you can use tin foil but you would be looking funny.
Oh well, if you'd *look* funny, you'd have to die then. :-)
And you would need to wear it all the time since the beam can be swept in within seconds to any place visible from the SPS.
Only if they could build it. They couldn't, because another country would blast it to pieces before it was finished.
even less so when you can smoke the launch facilities of anyone threatening you.
No. Which bit of 'easy to defend' didn't you understand? If the long words confused you, you only have to ask.
The problem is that in order to beam the microwaves down from geosynchronous orbit a huge antenna is needed to focus it down to even cell phone power density.
There's only two ways to up the power intensity in the beam:
a) build a bigger antenna in space (people would notice)
b) increase the power in the antenna (needs much bigger solar panels- people would notice)
Basically either way involves incredibly large amounts of money, and the weapon can't move so is easy to shoot at, easy to defend against (silver foil) and obvious.
It's really a non starter as far as weapons go.
Power. It takes an incredibly large amount of power to climb 38000 km to geosynchronous orbit.
It's ~500 KW per tonne of elevator to go at 200km/h near to the ground, but weight gradually reduces as you get nearer to geosynchronous orbit, and away from the earth and the power scales down proportionately.
The problem is, you can't carry enough fuel to get to the top (unless you use nuclear, but that's heavy).
Brad Edwards plan involves using ground based lasers to power photovoltaic panels.
Also, that's viruses you're talking about- what about worms?
Even if they don't- the government does :-(
Probably a baddddd idea.
The issue is that, in practice, a vast number of boxes on the internet are all vulnerable to attack- there's bound to be some hidden flaw in the incredible number of packages out there.
So the system can be up-to-date with all known patches, and still be attacked. Fining people for things that flat-out aren't their fault is likely to be, at best, contrary to the ISPs customers idea about what makes a good ISP.
I think the wing is more critical- as I understand it Space Ship One/the pilot will not survive without the wing pivoting. If the undercarriage fails he still stands some kind of chance.
If you leave the atmosphere tumbling out of control, you'll hit it out of control and you'll be far less likely to ever regain it. Indeed, at that air speed, as you drop you into thicker air out of control you are far more likely to suffer complete structural failure.
Actually- that's less of a problem for this vehicle than other ones. The reason the wing folds up and back is that in that position the vehicle is self stabilising- so during reentry Space Ship One will naturally take up an appropriate attitude.Of course, if the wing doesn't fold up at the right time- you're in for a bad day. AFAIK it's a safety critical item with no backup.
You must be a crooked person. :-)
If you don't do that you tend to thrash your processor's cache. And that's slow.
At the end of the day, you use the right tool for the job; I hsve heard of people doing bigger realtime jobs than that using LISP (they partially switched off the GC in that case).
But, because they used LISP, they had a competitive advantage- they could easily add complicated features- and were laughing all the way to the bank.
Sounds like a heck of a lot of fiddling about to me; and brittle code; change the sizes of the objects or allocate an extra object anywhere and suddenly your custom allocator runs like dog food.
I suppose it does depend on how you write the allocator, but it's still not sounding great to me; and if objects get deleted- you're looking at the potential for a *lot* of unused space.
That's the point about GC- it does pretty well most or all of the time.
Um. Both memory arenas and customer allocators are likely to make locality worse... the whole point about garbage collectors is that they compress the objects down and hence improve locality.
Give up. Who?