Well, they have in fact optimised the speed, so its really true optimisation. They haven't optimised the video quality; but then I guess most players prefer speed over quality that play Quake III so its kinda legitimate (kinda).
I mean if Quake III looked really bad, the card wouldn't sell; so there's checks and balances here atleast.
But it would have been much better if they had given the user some control of the video quality.
I ran babelfish on the page, the Germans suspect that the drivers run the display at 32 bit resolution, but drop the textures down to 16 bits.
Sounds a bit cheaky to me. The kind of screenrate you get with these cards is already very high, dropping the framerate for better resolution would be better for most people I suspect. If all this is right, the company has basically screwed their customers for a better benchmark, to sell more cards or to push the price up on the cards they sell. (IMHO).
Still, if you pay more for a graphics card for 10% extra performance when the performance is as high as this anyway, you are practically begging for them to trick you I suppose. Doesn't make it right though.
Hmm. You mean trust like they did with a previous Mars probe that accidentally reentered (may it rest in its pieces) due to a miscalculation over the size of the thruster?
>Mars is the only other place in the solar system that can support a truly interplanetary society.
Been reading Zubrin by any chance? The facts don't support this contention. Mars is pretty hostile, and lacks native power sources.
> Not true. Mars does indeed have a tenuous atmosphere, but that's not anything like a vacuum.
The pressure is negligable for most purposes. In fact the suits needed to survive it are full body pressure suits; very much the same as used on the moon.
> The radiation levels on Mars are far lower than those on any Near Earth Object.
True, but irrelevant. The radiation at a NEA will kill you in 10 years. The radiation on Mars will kill you in 30 years. You need around 1 m of shielding at Mars. It's physically easier to shield at the NEA due to lack of gravity though. True, you need more mass, about 1.5m, but mass is plentiful at NEAs and easy to position in zero-g. On Mars it weighs something.
> We have grown crops on Earth under domes for years - transporting the dome to Mars is the hardest part.
Not comparable. Greenhouses don't have to hold an atmosphere. Actually the problems are pretty similar in both NEA and Mars; except the sunlight at Mars is much less easy to control than that at NEAs. The evidence from Biosphere II show that just building an airtight dome cuts the sunlight significantly. And then you are at mars, so you are further away from the Sun as well. In fact domes are not a good shape for a pressure vessel; on earth only spheres or cylinders capped with spheres are permitted as there is a significant explosion risk from other shapes. Mars and NEAs would probably need cylindrical or spherical shapes to live in.
Mars has a quite large escape velocity (about 3km/s). Mars lacks continuous solar energy available off-planet.
>Large compared to what? Earth (at 11.2km/s)? Remember also that the escape velocity of an object does not by itself determine the delta-v than a spacecraft must perform to match orbits.
Yes, but that 3km/s is needed to escape it, ontop of any other delta-v. Mars is 3km/s further away. Not only that but that 3km/s requires high thust engines. Higher thrust costs more.
>Your argument for solar energy is specious, because for any sort of industrial operation, a power source more compact than solar is needed.
I don't know of ANY process that requires small power sources; industrial and farming sources require CHEAP energy; especially for crops. The evidence I have is that crops will grow poorly if at all on Mars unless you use nuclear power for grow lamps. However that requires extraordinarily high power levels (1kw per m^2 of field). Even a small field needs a power station. At a NEO, you just need thick windows.
A 30m wide parabola made of silver foil can give you more than 1 megawatt of heat, or 50% of that as electric power. Contrary to some peoples beliefs, solar ovens and solar power stations are trivial to build, particular in space. Smelting metal from certain ores is trivial using solar power; on Mars you've got big problems.
There is nothing that NEOs don't have, with the exception of gravity but that's pretty trivial to emulate with rotation. And we have no idea right now what effects 1/3 earth gravity has on peoples bodies; but it could well damage them. People at NEOs can be given a full gravity.
>If you're talking about tonnes of material (more on that in a moment), what sort of delta vee are you
>looking at?
I don't have any particular target, but about 3 km/s sounds about right for a lunar capture and/or aerobraking. That's easily done with Hall effect thrusters, although you'd probably need more than several thrusters as they wear out. Fortunately they don't weigh much.
>NASA would dearly love to get their hands on that amount of pristine asteroidal material. If it could be done for $200 million,
>they'd be doing it already.
I don't think that is the case. Don't forget they've only just done their first mission with ion drives. This requires ion drives.
>As for finding asteroids that weigh tons, how do you propose to do that? The only way we have to detect rocks that size at the
>moment is when they hit our atmosphere (and, shortly thereafter, the Earth). Any asteroid that we can track (and thus rendezvous
>with) doesn't weigh "hundreds of tonnes", it weighs millions or billions of tons.
Dunno. Look for a NEAr miss? Chip a bit off a bigger one with explosives?
I think you are looking at the problems and the failures and ignoring the successes completely. Sanity lies somewhere inbetween.
- the cable didn't snap, it burnt through due to high current flows. These current flows do not exist at asteroids (no magnetic field)
- I don't agree that that his way of despinning an asteroid is necessarily a good one, but I think that there are other techniques that will work, particularly with small asteroids that you can drag back whole (there's more small asteroids than big ones anyway).
- ripples in mirrors degrade their efficiency, they don't stop them working.
- return missions from small (meter size) asteroids are much cheaper than returns from Mars, and we get more stuff back.
It is not the case that it would cost billions to get to NEA and back. A mining mission can be done for initially about $200 million, about the same cost as DS1. We're not talking hundreds of tonnes returned, we're talking tonnes. But the mining vehicles would be very reusable, and can make a new trip per year or so, with a few hundred kilograms of refueling requirements each trip.
This is not most people's idea of space mining, but I think that having asteroid material returned to the ISS would give it a purpose.
In particular it may be possible to get some or all of the fuel for the mining probes from the asteroidal material in LEO. If that can be done then we can look at turning a (very modest) profit.
The point is economic. The sooner we start on commercial exploitation of space, the sooner we get to go. In order to go, we need to show profit. If profit can be show, then investment follows. Investment leads to greater volumes, and greater volumes leads to much, much lower price.
>Its 'cheaper' in terms of fuel expenditure. In the real world of today, however, you would have to factor in the many billions of
>dollars that setting up your NEA fuel depot would cost. One day it will be the way to go, but your argument is like saying that we
>shouldn't spend millions on developing better silicon chip lithography because one day quantum computing will be much better.
No. Quantum computing doesn't scale right now. This does. It's more like saying, hey why don't we fund silicon chips because silicon chips are cheaper than discrete!
Going to Mars is not necessary or sufficient to become an interplanetary sociey.
Mars is more like the moon than earth. The atmosphere is less than 1% of the earths, that's practically a vacuum. The radiation levels on the surface are high, the problems of growing stuff under domes are extreme. Mars has a quite large escape velocity (about 3km/s). Mars lacks continuous solar energy available off-planet. That's probably very, very important for technological societies.
NEAs are closer than Mars, have better distribution of materials than Mars, have a clearer path to self sufficiency than Mars, are accessible to robot probes with much lower thrust levels than Mars; and allows for exporting materials back to Earth at much lower cost than Mars.
Mars does not have any higher lifeforms, and does not seem to have any lower lifeforms either.
Even phobos is a better bet than Mars in the short term.
Space mining is NOT at all unrealistic. Space mining is able to make possible safe, manned travel to Mars; and cheaper access to space from the earth- space tourism can be achieved more cheaply using space resources. Space mining IS being very seriously looked at by companies.
Whether America has woken up to this is largely irrelevant I guess. The markets have far more money than government. You also seemed to have missed the fact that NASA does not exactly a monopoly on space right now.
Still, I am not anti Mars at all. We should go to Mars, but we need to go to NEAs first to get the materials we need to do that.
its a much better idea to bring back a near earth asteroid (NEA), or mine a near earth asteroid and bring back the good bits.
Why?:
a) NEA's are nearer
b) mining asteroids can turn a profit (Mars probably can't)
c) we can use ION drives to get there (like Deep Space 1 used), but they don't work to-from Mars due to the gravity of Mars
d) there's no chance that we catch the never-get-overs (the asteroids should be dead)
e) they contain useful stuff like water (steam is a fairly good rocket fuel in fact)
f) getting lots of stuff from NEAs to orbit is looking cheaper than getting it from the earth, therefore it may be possible to send people to Mars using the fuel collected from NEAs; in the meantime we can turn a profit boosting satellites into GEOsynchronous orbit and such like...
g) Basically Mars would be a white elephant right now. Cool as heck, but pointless.
I don't think he is a troll, although a lot of people will think so. To implement RSA you only need to multiply, add, and find the remainder on a large number.
There's a T-shirt with an implementation in Perl; theoretically it's illegal to export from the US; but it probably comes under 'free speech'.
> It will pass the sniffer, but will still be unreadable if somebody
> gets a warrant and uses the escrowed key on the outer crypto.
Nah. After they blow away the escrowed encryption on the data they run a simple 'is this any known language test' on it [these are used extensively in cryptanalysis] (e.g. check letter frequencies or something more complex). If it comes back negative they look at it some more, and if it appears encrypted they send around the boys in blue.
Incidentally, the warrant concept is probably a real laugh a minute. Probably they have a law that allows them access to just about anything for national security reasons, or they have a pet judge, or they don't care [see arms for hostages]. You can bet there's some angle going there.
The security agencies are already checking through most or a statistical useful percentage of the bytes that flow over the US internet, and are characterising it all. Their actions only make sense if they are doing that.
Anyone using encryption stands out; so they write a file on them.
Where they find encrypted data they can't characterise it any further; so they hit a brick wall. But its not common right now, so they can make a file. However, if everyone on the internet routinely uses uncrackable encryption they can't build a file on everyone.
On the other hand, if they have key escrow they can blow away the encryption on all the legitimate data and they are left with 'illegal' encryption; except presumably terrorists and other malcontents; a much smaller group that they can write files on.
Of course this 'monitor all the traffic on the internet idea' falls down in several other ways. As an example, suppose somebody creates a Quake III server that has some sort of low bandwidth messaging in it perhaps the player steps left at careful timed moments or something, the characterisation by the NSA would be, oh its just another Quake player, when really its sending an encrypted message as well. [I just made that Quake idea up- its called 'steganography' in general, hiding encrypted messages in something else.]
Anyway, that's really what's going on. The security agencies are using the WTC disaster as a chance to get their legislation through whilst the going is good. Of course anyone with any sense can evade it, but not every terrorist has sense.
Me too. Based only on a short newspaper article I read in the 'The Daily Telegraph' when I was 16 and implemented it in a week in assembly. And now there are detailed papers available on how to do it on the internet.
I don't see the point at all. Terrorists won't use the escrowed codes; and there are probably plenty of ways to hide messages where the law enforcement agencies won't notice them.
The reason that France had the law in the first place was because they gained an edge because they were able to snoop on conversations between foreign nationals negotiating aerospace contracts in France!
A GUID would be good, so would a hash. However if a file gets truncated a simple hash gets all messed up.
I don't think the file will be corrupted if it comes from different servers. By ensuring you have an overlap in the fragments you collect you can ensure that they are the same file. The chances of two different files being the same over say, 128 consecutive bytes is very low for most files (mp3, mpeg, binaries).
Also, if you introduce some randomness in where you start requesting each fragment, it becomes more difficult for someone to deliberately construct files that only match in the middle, but all the other bits sound like a cuckoo clock...
The best system is actually a heirarchical hash. First you hash all the 256 byte blocks. Then you write the hashes consecutively and hash each 256 byte block of that, write them consecutively and hash that and so on, until you have a single hash of the hashed hashes. That is the file GUID.
All this gets prepended to the file, and then people can then download the blocks in any order and be sure they've got it all right.
I think this is how MojoNation works, but I haven't checked. The protocol is proof against deliberate tampering with the file, although it isn't proof against people misrepresenting a file's contents in the first place- still you can always play the file before you've finished with most browsers.
Yes, this concept isn't new- although as you say I don't think it is available for gnutella yet.
Another thing that Gnutella doesn't make use of right now is the partial downloads. If I've downloaded 1/2 the file, it usually doesn't appear on anyones search. If fragments are stored in the searchable directory we can effectively get more results, which means better download speed for everyone, cos there's probably lots of upload bandwidth out there right now going spare.
I don't think this will necessarily make it more bandwidth efficient however, but it would make it much, much, more useful.
This isn't exactly true. Java and C/C++ are very similar in performance if you use them the same way.
There's no reason that I am aware of why Java and C can't have identical speed if coded carefully. However people use Java because they don't have to and don't want to code that way.
(There is some handwaving above- some of the Java I/O libraries are a bit slow; that's a library issue, rather than a language issue though.)
One thing I've always wanted was to just specify a file and leave it to go get it and download it itself.
In particular if 5 sites have the file I should be able to connect to all 5 of them (or try to) and download different parts of the file in parallel; the protocol allows you to start wherever you want to.
The total load on the network is the same because I'm only connected to each server for 1/5 the time, but I would usually get it faster.
Of course sometimes, one of the files is corrupted or something- it's possible to check the ends of the fragments and splice them correctly or ignore any bits that don't fit.
NASA now have a policy of destroying their equipment at the end of missions. Otherwise they find that the budget for the mission gets extended and takes away from the other missions they want to fund. I got the impression that this was another 'let's see if we can kill this thing' mission.
Of course the operators usually try to arrange it that the thing makes it through somehow...
It's all very well being unpredictable, or smart. But sometimes you can be smartest by knowing how stupid you really are. Shouldn't be that difficult for Bush. I hope he picks the right people to make the right decisions.
(Incidentally, the normal view is that the German soldiers were a percentage better per man than the Allies; individuality does not seem to help in war.)
And yes I will stick my neck out and say that the Slashdot readership will not develop the technology of the warp drive in the next ten years.
>most people are used to the idea of "my" computer, "my" data, and everything happening physically
>*here*, inside this little box under my desk. This will take a long time to get over.
Well, get over it. Now!;-)
Where I work we run Unix of various flavours. We run as dataless clients over NFS. This means that my home directory is on the server, and Unix is on the machines local disk. Latency is a non issue- ping times of about 1ms; throughput isn't quite so high though, as we only use a 10 megabit lan, so if we load across the network it isn't as fast as loading off a local disk, but there's not a lot in it. (Extra 2 minutes on a 150 megabyte link that takes 6 minutes is the worst case; we often use local diskspace for that, but everything else there's no point).
It works pretty well. And if I have a problem with my workstation I get up, sit down at a different workstation, and log in there, same account, same files.
It also means that my home directory is backed up each and every night by the backup fairy. (We have only 1 system admin for 80-100 people!)
As to security, it's not a real issue. You either access your account from a company machine, which is as secure as anything, or from home, where you keep your system safe (hopefully) there.
Games? Games don't require zero latency! If they did, noone would be able to play them because zero latency doesn't exist.
We're not really talking about audio in this context I think, but certainly 12ms delay can cause issues with echo/feedback in some audio apps, but throwing large amounts of digital signal processing makes these non issues; and processing is getting exponentially cheaper all the time.
>Video is even worse affected by jitter in the
time domain.
There is no direct connection at all between Jitter and latency.
Slashdot Mirror
Well, they have in fact optimised the speed, so its really true optimisation. They haven't optimised the video quality; but then I guess most players prefer speed over quality that play Quake III so its kinda legitimate (kinda).
I mean if Quake III looked really bad, the card wouldn't sell; so there's checks and balances here atleast.
But it would have been much better if they had given the user some control of the video quality.
I ran babelfish on the page, the Germans suspect that the drivers run the display at 32 bit resolution, but drop the textures down to 16 bits.
Sounds a bit cheaky to me. The kind of screenrate you get with these cards is already very high, dropping the framerate for better resolution would be better for most people I suspect. If all this is right, the company has basically screwed their customers for a better benchmark, to sell more cards or to push the price up on the cards they sell. (IMHO).
Still, if you pay more for a graphics card for 10% extra performance when the performance is as high as this anyway, you are practically begging for them to trick you I suppose. Doesn't make it right though.
Hmm. You mean trust like they did with a previous Mars probe that accidentally reentered (may it rest in its pieces) due to a miscalculation over the size of the thruster?
>Mars is the only other place in the solar system that can support a truly interplanetary society.
Been reading Zubrin by any chance? The facts don't support this contention. Mars is pretty hostile, and lacks native power sources.
> Not true. Mars does indeed have a tenuous atmosphere, but that's not anything like a vacuum.
The pressure is negligable for most purposes. In fact the suits needed to survive it are full body pressure suits; very much the same as used on the moon.
> The radiation levels on Mars are far lower than those on any Near Earth Object.
True, but irrelevant. The radiation at a NEA will kill you in 10 years. The radiation on Mars will kill you in 30 years. You need around 1 m of shielding at Mars. It's physically easier to shield at the NEA due to lack of gravity though. True, you need more mass, about 1.5m, but mass is plentiful at NEAs and easy to position in zero-g. On Mars it weighs something.
> We have grown crops on Earth under domes for years - transporting the dome to Mars is the hardest part.
Not comparable. Greenhouses don't have to hold an atmosphere. Actually the problems are pretty similar in both NEA and Mars; except the sunlight at Mars is much less easy to control than that at NEAs. The evidence from Biosphere II show that just building an airtight dome cuts the sunlight significantly. And then you are at mars, so you are further away from the Sun as well. In fact domes are not a good shape for a pressure vessel; on earth only spheres or cylinders capped with spheres are permitted as there is a significant explosion risk from other shapes. Mars and NEAs would probably need cylindrical or spherical shapes to live in.
Mars has a quite large escape velocity (about 3km/s). Mars lacks continuous solar energy available off-planet.
>Large compared to what? Earth (at 11.2km/s)? Remember also that the escape velocity of an object does not by itself determine the delta-v than a spacecraft must perform to match orbits.
Yes, but that 3km/s is needed to escape it, ontop of any other delta-v. Mars is 3km/s further away. Not only that but that 3km/s requires high thust engines. Higher thrust costs more.
>Your argument for solar energy is specious, because for any sort of industrial operation, a power source more compact than solar is needed.
I don't know of ANY process that requires small power sources; industrial and farming sources require CHEAP energy; especially for crops. The evidence I have is that crops will grow poorly if at all on Mars unless you use nuclear power for grow lamps. However that requires extraordinarily high power levels (1kw per m^2 of field). Even a small field needs a power station. At a NEO, you just need thick windows.
A 30m wide parabola made of silver foil can give you more than 1 megawatt of heat, or 50% of that as electric power. Contrary to some peoples beliefs, solar ovens and solar power stations are trivial to build, particular in space. Smelting metal from certain ores is trivial using solar power; on Mars you've got big problems.
There is nothing that NEOs don't have, with the exception of gravity but that's pretty trivial to emulate with rotation. And we have no idea right now what effects 1/3 earth gravity has on peoples bodies; but it could well damage them. People at NEOs can be given a full gravity.
It's not correct. I've been looking at designing a rocket, so trust me I know. Liquid Hydrogen has 1/6 the energy density of aviation fuel by volume.
>Microsoft developers (in the words of Ballmer) are only human as well -- and I'm sure they work just as hard as we do.
;-)
Harder! Because evil never sleeps...
>Recent investigations have called into question whether inflatable mirrors would
>be ripple-free enough to use as space telescopes or antennas.
Irrelevant. We are talking about solar ovens. Space telescopes and antennas have to be accurate to a fraction of a wavelength. Solar ovens do not.
I take it you've never built a solar oven? You should try it, it's not hard...
>If you're talking about tonnes of material (more on that in a moment), what sort of delta vee are you
>looking at?
I don't have any particular target, but about 3 km/s sounds about right for a lunar capture and/or aerobraking. That's easily done with Hall effect thrusters, although you'd probably need more than several thrusters as they wear out. Fortunately they don't weigh much.
>NASA would dearly love to get their hands on that amount of pristine asteroidal material. If it could be done for $200 million,
>they'd be doing it already.
I don't think that is the case. Don't forget they've only just done their first mission with ion drives. This requires ion drives.
>As for finding asteroids that weigh tons, how do you propose to do that? The only way we have to detect rocks that size at the
>moment is when they hit our atmosphere (and, shortly thereafter, the Earth). Any asteroid that we can track (and thus rendezvous
>with) doesn't weigh "hundreds of tonnes", it weighs millions or billions of tons.
Dunno. Look for a NEAr miss? Chip a bit off a bigger one with explosives?
I think you are looking at the problems and the failures and ignoring the successes completely. Sanity lies somewhere inbetween.
- the cable didn't snap, it burnt through due to high current flows. These current flows do not exist at asteroids (no magnetic field)
- I don't agree that that his way of despinning an asteroid is necessarily a good one, but I think that there are other techniques that will work, particularly with small asteroids that you can drag back whole (there's more small asteroids than big ones anyway).
- ripples in mirrors degrade their efficiency, they don't stop them working.
- return missions from small (meter size) asteroids are much cheaper than returns from Mars, and we get more stuff back.
It is not the case that it would cost billions to get to NEA and back. A mining mission can be done for initially about $200 million, about the same cost as DS1. We're not talking hundreds of tonnes returned, we're talking tonnes. But the mining vehicles would be very reusable, and can make a new trip per year or so, with a few hundred kilograms of refueling requirements each trip.
This is not most people's idea of space mining, but I think that having asteroid material returned to the ISS would give it a purpose.
In particular it may be possible to get some or all of the fuel for the mining probes from the asteroidal material in LEO. If that can be done then we can look at turning a (very modest) profit.
The point is economic. The sooner we start on commercial exploitation of space, the sooner we get to go. In order to go, we need to show profit. If profit can be show, then investment follows. Investment leads to greater volumes, and greater volumes leads to much, much lower price.
>Its 'cheaper' in terms of fuel expenditure. In the real world of today, however, you would have to factor in the many billions of
>dollars that setting up your NEA fuel depot would cost. One day it will be the way to go, but your argument is like saying that we
>shouldn't spend millions on developing better silicon chip lithography because one day quantum computing will be much better.
No. Quantum computing doesn't scale right now. This does. It's more like saying, hey why don't we fund silicon chips because silicon chips are cheaper than discrete!
Going to Mars is not necessary or sufficient to become an interplanetary sociey.
Mars is more like the moon than earth. The atmosphere is less than 1% of the earths, that's practically a vacuum. The radiation levels on the surface are high, the problems of growing stuff under domes are extreme. Mars has a quite large escape velocity (about 3km/s). Mars lacks continuous solar energy available off-planet. That's probably very, very important for technological societies.
NEAs are closer than Mars, have better distribution of materials than Mars, have a clearer path to self sufficiency than Mars, are accessible to robot probes with much lower thrust levels than Mars; and allows for exporting materials back to Earth at much lower cost than Mars.
Mars does not have any higher lifeforms, and does not seem to have any lower lifeforms either.
Even phobos is a better bet than Mars in the short term.
Space mining is NOT at all unrealistic. Space mining is able to make possible safe, manned travel to Mars; and cheaper access to space from the earth- space tourism can be achieved more cheaply using space resources. Space mining IS being very seriously looked at by companies.
Whether America has woken up to this is largely irrelevant I guess. The markets have far more money than government. You also seemed to have missed the fact that NASA does not exactly a monopoly on space right now.
Still, I am not anti Mars at all. We should go to Mars, but we need to go to NEAs first to get the materials we need to do that.
its a much better idea to bring back a near earth asteroid (NEA), or mine a near earth asteroid and bring back the good bits.
Why?:
a) NEA's are nearer
b) mining asteroids can turn a profit (Mars probably can't)
c) we can use ION drives to get there (like Deep Space 1 used), but they don't work to-from Mars due to the gravity of Mars
d) there's no chance that we catch the never-get-overs (the asteroids should be dead)
e) they contain useful stuff like water (steam is a fairly good rocket fuel in fact)
f) getting lots of stuff from NEAs to orbit is looking cheaper than getting it from the earth, therefore it may be possible to send people to Mars using the fuel collected from NEAs; in the meantime we can turn a profit boosting satellites into GEOsynchronous orbit and such like...
g) Basically Mars would be a white elephant right now. Cool as heck, but pointless.
I don't think he is a troll, although a lot of people will think so. To implement RSA you only need to multiply, add, and find the remainder on a large number.
There's a T-shirt with an implementation in Perl; theoretically it's illegal to export from the US; but it probably comes under 'free speech'.
> It will pass the sniffer, but will still be unreadable if somebody
> gets a warrant and uses the escrowed key on the outer crypto.
Nah. After they blow away the escrowed encryption on the data they run a simple 'is this any known language test' on it [these are used extensively in cryptanalysis] (e.g. check letter frequencies or something more complex). If it comes back negative they look at it some more, and if it appears encrypted they send around the boys in blue.
Incidentally, the warrant concept is probably a real laugh a minute. Probably they have a law that allows them access to just about anything for national security reasons, or they have a pet judge, or they don't care [see arms for hostages]. You can bet there's some angle going there.
The security agencies are already checking through most or a statistical useful percentage of the bytes that flow over the US internet, and are characterising it all. Their actions only make sense if they are doing that.
Anyone using encryption stands out; so they write a file on them.
Where they find encrypted data they can't characterise it any further; so they hit a brick wall. But its not common right now, so they can make a file. However, if everyone on the internet routinely uses uncrackable encryption they can't build a file on everyone.
On the other hand, if they have key escrow they can blow away the encryption on all the legitimate data and they are left with 'illegal' encryption; except presumably terrorists and other malcontents; a much smaller group that they can write files on.
Of course this 'monitor all the traffic on the internet idea' falls down in several other ways. As an example, suppose somebody creates a Quake III server that has some sort of low bandwidth messaging in it perhaps the player steps left at careful timed moments or something, the characterisation by the NSA would be, oh its just another Quake player, when really its sending an encrypted message as well. [I just made that Quake idea up- its called 'steganography' in general, hiding encrypted messages in something else.]
Anyway, that's really what's going on. The security agencies are using the WTC disaster as a chance to get their legislation through whilst the going is good. Of course anyone with any sense can evade it, but not every terrorist has sense.
Me too. Based only on a short newspaper article I read in the 'The Daily Telegraph' when I was 16 and implemented it in a week in assembly. And now there are detailed papers available on how to do it on the internet.
I don't see the point at all. Terrorists won't use the escrowed codes; and there are probably plenty of ways to hide messages where the law enforcement agencies won't notice them.
Wow. I hadn't heard that; that is awesome!
;-)
The reason that France had the law in the first place was because they gained an edge because they were able to snoop on conversations between foreign nationals negotiating aerospace contracts in France!
If that's true that would be so sweet...
Do you have any references to that?
A GUID would be good, so would a hash. However if a file gets truncated a simple hash gets all messed up.
I don't think the file will be corrupted if it comes from different servers. By ensuring you have an overlap in the fragments you collect you can ensure that they are the same file. The chances of two different files being the same over say, 128 consecutive bytes is very low for most files (mp3, mpeg, binaries).
Also, if you introduce some randomness in where you start requesting each fragment, it becomes more difficult for someone to deliberately construct files that only match in the middle, but all the other bits sound like a cuckoo clock...
The best system is actually a heirarchical hash. First you hash all the 256 byte blocks. Then you write the hashes consecutively and hash each 256 byte block of that, write them consecutively and hash that and so on, until you have a single hash of the hashed hashes. That is the file GUID.
All this gets prepended to the file, and then people can then download the blocks in any order and be sure they've got it all right.
I think this is how MojoNation works, but I haven't checked. The protocol is proof against deliberate tampering with the file, although it isn't proof against people misrepresenting a file's contents in the first place- still you can always play the file before you've finished with most browsers.
Yes, this concept isn't new- although as you say I don't think it is available for gnutella yet.
Another thing that Gnutella doesn't make use of right now is the partial downloads. If I've downloaded 1/2 the file, it usually doesn't appear on anyones search. If fragments are stored in the searchable directory we can effectively get more results, which means better download speed for everyone, cos there's probably lots of upload bandwidth out there right now going spare.
I don't think this will necessarily make it more bandwidth efficient however, but it would make it much, much, more useful.
This isn't exactly true. Java and C/C++ are very similar in performance if you use them the same way.
There's no reason that I am aware of why Java and C can't have identical speed if coded carefully. However people use Java because they don't have to and don't want to code that way.
(There is some handwaving above- some of the Java I/O libraries are a bit slow; that's a library issue, rather than a language issue though.)
One thing I've always wanted was to just specify a file and leave it to go get it and download it itself.
In particular if 5 sites have the file I should be able to connect to all 5 of them (or try to) and download different parts of the file in parallel; the protocol allows you to start wherever you want to.
The total load on the network is the same because I'm only connected to each server for 1/5 the time, but I would usually get it faster.
Of course sometimes, one of the files is corrupted or something- it's possible to check the ends of the fragments and splice them correctly or ignore any bits that don't fit.
NASA now have a policy of destroying their equipment at the end of missions. Otherwise they find that the budget for the mission gets extended and takes away from the other missions they want to fund. I got the impression that this was another 'let's see if we can kill this thing' mission.
Of course the operators usually try to arrange it that the thing makes it through somehow...
It's all very well being unpredictable, or smart. But sometimes you can be smartest by knowing how stupid you really are. Shouldn't be that difficult for Bush. I hope he picks the right people to make the right decisions.
(Incidentally, the normal view is that the German soldiers were a percentage better per man than the Allies; individuality does not seem to help in war.)
And yes I will stick my neck out and say that the Slashdot readership will not develop the technology of the warp drive in the next ten years.
>most people are used to the idea of "my" computer, "my" data, and everything happening physically
;-)
>*here*, inside this little box under my desk. This will take a long time to get over.
Well, get over it. Now!
Where I work we run Unix of various flavours. We run as dataless clients over NFS. This means that my home directory is on the server, and Unix is on the machines local disk. Latency is a non issue- ping times of about 1ms; throughput isn't quite so high though, as we only use a 10 megabit lan, so if we load across the network it isn't as fast as loading off a local disk, but there's not a lot in it. (Extra 2 minutes on a 150 megabyte link that takes 6 minutes is the worst case; we often use local diskspace for that, but everything else there's no point).
It works pretty well. And if I have a problem with my workstation I get up, sit down at a different workstation, and log in there, same account, same files.
It also means that my home directory is backed up each and every night by the backup fairy. (We have only 1 system admin for 80-100 people!)
As to security, it's not a real issue. You either access your account from a company machine, which is as secure as anything, or from home, where you keep your system safe (hopefully) there.
Games? Games don't require zero latency! If they did, noone would be able to play them because zero latency doesn't exist.
We're not really talking about audio in this context I think, but certainly 12ms delay can cause issues with echo/feedback in some audio apps, but throwing large amounts of digital signal processing makes these non issues; and processing is getting exponentially cheaper all the time.
>Video is even worse affected by jitter in the
time domain.
There is no direct connection at all between Jitter and latency.