I heard that, but my old Daewoo TV set doesn't like decoding text off my cable box {NTL, pace 4000 series}. It was never much cop decoding it off the air. I thought that could be to do with the fact that I live so far down in the bottom of a valley, I have to go uphill to get to the river!
In the TV's defence, however, it does use the same codeset as a Philips telly, and therefore my DVD recorder remote lets me adjust my TV volume (text is all but unusable, picture is set right, cable box usually changes station unless recording a movie off Sky). So I'm half happy at least.
About connecting two appliances to one SCART socket: it will only ever work if only one output device is ever switched on at a time. When an op-amp -- strictly, any class AB output stage -- is unpowered, its output is high-impedance {both transistors are off}. When it's powered and amplifying, its output is quite low-impedance and will happily sink any signal coming from the other output.
Hey, they don't even have proper colour in the USA! Things on the TV screen appear in colours as opposed to shades of grey, but the colour of the TV image usually is not the same as the colour of the real thing. That's the disadvantage of NTSC {where DC offsets tend to cause cumulative errors thanks to parasitic capacitances behaving as integrators} versus PAL {where errors due to DC offsets tend to cancel one another out very quickly, because the signal is inverted on every other line}. Also, the higher frequency PAL colour carrier allows for more bandwidth.
When we show the snooker on BBC2 -- and you have to watch the snooker if you've got a colour TV set, it's the law -- the table is green; there are fifteen red balls, and the coloured balls go: yellow, green, brown, blue, pink, black. In the States, to show a snooker match that anyone watching TV could understand, they would have to use a blue table, fifteen yellow balls, and the colours are orange, sky-blue, red, violet, creamy-white with little brown spots and black (which transmits fine). And there would be an advert break after every shot. Needless to say this does not help the players much. They tried showing pool on TV instead, but it was very disconcerting to be told the red player was winning when there appeared still to be seven reds on the table and the guy with the cue in his hand was taking aim at what appeared to be a yellow ball.
To modify Schneier's Law a little, anybody can write a piece of software so secure that they themself cannot crack it.
In the open source camp, nobody needs to write a JPEG viewer, because it's already been done once, and done right. Only the closed source crowd can't touch it, because we wrote it for everyone to share, not for some people to lock away. So they have to write their own, and they still get it wrong.
All the claimed faults with Windows really come down to one failing, and it isn't one that Microsoft is going to do anything about: No access to the source code. The only way to ever be certain what any piece of software does is by examining the source code.
I've run right out of sympathy for Windows users. If you are still running Windows after all this, you deserve everything that happens to you. Understand this one thing: Windows is never, ever going to get any better. It can't; because as long as good guys outnumber bad, closed source will always be less secure than open source. Cut your losses now and switch to a better operating system. You can live without your favourite Windows applications; but the longer you leave it, the harder it will get.
No, it's not just a threat. It's perjury on the MPAA's part {under US law}. It's also libel {under Aussie law} if the takedown notice was shown to an upstream ISP; otherwise {and probably even if so anyway} it's harassment occasioning distress or alarm* {under Aussie law}.
Unfortunately, libel is only a civil offence, so there can be no grounds for extradition. Which is a shame, because if the Australian legal system is anything like ours, the loser of a court case pays all court costs. But perjury is a crime in Australia, so the MPAA might be extraditable to Australia for that, and if harassment is a crime in the USA then they might also be extraditable on that count too. However, you can't extradite someone to be sentenced to a harsher penalty than they would face back home.
* That's actually a UK offence; I am guessing Australia has a similar one on its statute books.
A centrifugal switch does actually sound like a better way of doing it..... unless there are other problems..... You could emulate it perfectly, electronically, by having positional feedback, but it'd cost more than a simple delay switch.
I think DC brushless is still overall the best way to do it, though. (And you need positional feedback, which you get from Hall-effect or optical sensors, so you know the motor is going round). Especially polyphase -- which can even run without a permanent magnet, since the armature is always lining up between lines of flux. But then, I'm biased..... I just like DC brushless motors!
Microsoft software is closed-source. As a consequence of this, the good guys (who vastly outnumber bad guys) are not allowed to look at the code and spot potential security holes, suggest fixes &c. Meanwhile, bad guys look at the code anyway, permission or not, spot the security holes and write software which takes advantage of them.
Symantec sell anti-virus software. This
software is closed-source. As a consequence of this, everyone who wants a copy has to pay for it. Plus, the good guys (who outnumber the bad guys) are not allowed to examine and improve it; while the bad guys examine it anyway and take advantage of any opportunity to exploit it.
Symantec basically exploits the disadvantaged -- people who, through no fault of their own, have had something unpleasant happen to their computer -- for financial gain. If someone is running Windows, it's not really their fault that Windows is insecure. After all, it was already on the computer when they bought it (thanks to Microsoft's illegal monopoly), and it appeared to work out of the box.
Imagine if a restaurant sold food that made you constipated, knew that it made you constipated, and didn't do anything about it except suggest you buy some laxatives from the chemist across the street. Would anybody put up with that? It's crazy that in the realm of computers, people can and do get away with this sort of stuff all the time. I think it's all to do with how, in the late 1970s, someone at VisiCorp got worried in case someone designed a road bridge with the help of VisiCalc {a then-popular spreadsheet}, it collapsed, and VisiCorp got some of the blame.
The ONLY way you can ever be sure your software will do what you want, exactly what you want and nothing but what you want, is to read the source code -- or get somebody with nothing to gain from lying to you to do that for you. And if the supplier won't let you read the source code then screw them - they are no good.
I think you misread what I was talking about. What you say makes sense in its own right, but it doesn't have anything to do with what I said.
Unless you pull some stunts, a single phase induction motor will never start from rest, because the only thing magnetising the armature is the induced current due to the difference in rotational speeds between the armature itself and the "revolving field" (which, with just one set of windings, is more like a collapsing and expanding field). One solution is to use a "shade" (a single or double shorted turn of thick copper wire) on one pole piece to deliberately distort the magnetic field, and so give the armature an initial kick; but this makes the motor inefficient and so isn't practical for anything bigger than a few watts. Another, which doesn't introduce so many losses, is to use a second stator winding with pole pieces at 90 degrees to the first, and energise this with current 90 degrees out of phase with the first winding. Now you really do have a true revolving field -- and as a bonus, you have twice the magnetism available, which gives you extra torque (which you typically need at starting anyway). But, due to the fact that the electrical phase shift (due to the capacitor) is not exactly equal to the mechanical phase shift (due to the offset windings), this will introduce losses. Fortunately, once the motor is running, you can switch off one of the windings and it will carry on rotating.
In a manual-start application, it is easy to have a switch with "stop", "run" and "start" positions and spring-loaded so it will go from "start" to "run" when released. But in a thermostatically controlled application, you need a device to automatically apply power to the starter winding just for long enough that the motor catches, then disconnect it. Traditionally that device is a thermal relay (heater and bi-metallic strip). The heater is connected in parallel with the running winding. When cold, the bi-metallic strip is touching a contact that completes the circuit through the capacitor and starter winding. As the strip heats up, it bends away from the contact and disconnects the starter winding. However, if it is not getting hot enough to bend (due to low voltage; recall that P = E ** 2 / R, so a drop of 10% voltage means 20% less power), then it will stay connected. This means the starter winding will stay in circuit and the motor will overheat.
A thermal relay introduces a loss of its own, of course; but it's typically only a watt or so. If this is less than the loss due to having the motor run in split-phase mode full time, and less than the loss due to using shaded poles, it's still a saving.
The reason why conventional air conditioning units {and refrigerators -- a fridge is just a cupboard with its own air-con venting into the kitchen} are sensitive to voltage drops, is the kind of motor they use to drive the compressor; a capacitively-started induction motor. The idea is that once the motor has started, a time delay relay disconnects the starter winding. This time delay relay typically uses a simple bimetallic strip and heater coil arrangement; in pre-semiconductor times, this was about the only way to do it, and it just kind of stuck. At first, the strip is touching a contact which sends current through the capacitor and starter winding; as it heats up, it bends away from the contact and cuts the power to the starter winding, so only the main winding is powered. If you don't use the starter winding then the motor will sit still (unless you spin the armature by some external means).
The problem is that at low voltages, the heater doesn't get hot enough to open the bi-metallic switch. The starter winding stays connected all the time and the motor draws about double the power it should..... and gets hotter than it should. Now, if the delay relay were mounted in good thermal contact with the motor, then it would be helped to operate by the excess heat building up in there; but that huge hefty chunk of a motor would slow down the resetting action. This means next time the refrigerator's thermostat is calling for cooling, the motor won't start because the delay relay is now in the "run" position. So the motor just gets hotter and hotter. And he fridge certainly isn't getting any cooler, so the thermostat won't open in a hurry. It has actually been known for fridges to fail castastrophically under low-voltage conditions!
(As an aside, I know that an electronic delay relay could be built that would do the same job, but using a simple R-C delay circuit coupled to a conventional electromagnetic relay, for about 50p in bulk. Maybe modern fridges do actually use this kind of thing instead.)
If you wanted to build an air conditioner that was really immune to supply fluctuations, the obvious choice would be a DC brushless motor. You could run it from mains via a switch mode supply -- they're cheap as chips nowadays -- or straight from DC. Brushless motors are quite tolerant of voltage variations anyway, as long as you can get enough whack to shift the spindle and not so much as to damage the transistors in the drive circuit. And it would also be an idea to give a refrigerator a chimney of its own, so as to dispose of the hot air it produces directly rather than relying on your home's aircon to shift it. If you added a nice big air relief opening, the draught thus created should help to cool the kitchen. In winter, you could divert the fridge flue into an upstairs room (you don't want to get it back anywhere near the fridge). With an aircon, you probably could do something sensible with the meltwater from the ice that builds up on the evaporator, too.
Exactly -- there are plenty of comments in all the config files, and the way Slackware startup works is easier for a n00b to understand than most Linux distros {in the same sort of way that 6502 machine code is easier for a n00b to understand than Z80 machine code, if that isn't showing my age}.
I started out with Debian, found it a bit awkward {I was fine at the command line, but X, which I wanted to get into, was an absolute mystery to me}; and went with Mandrake instead. It let me install both KDE and GNOME, plus a few other window managers just to be sure; I found KDE was my favourite. And I gradually twigged onto how the graphical tools were causing changes in the config files. By the time I knew I'd outgrown Mandrake, I was more confident about returning to Debian. Since then, I have played with Slackware, and I really do kind of like it; it's just that my Debian system really hasn't given me cause to think about moving on, and changing distros just for the sake of it would be a violation of the KISS principle that underlies Slackware.
But if Slackware gets something really cool that Debian doesn't, I'll certainly consider it seriously.
/* Sieve of Eratosthenes: a program to find prime numbers */
int main() { int start_at = 5; int up_to = 200; int miss = 2; /* We implicitly eliminate all multiples of 2 and 3 by starting at 5, and alternately skipping 2 and 4. So, every number we look at is either 6n+1 or 6n+5. This is because;
6n = multiple of 2 and 3 6n+2 = even 6n+3 = multiple of 3 6n+4 = even */ int remainder, i, j, k, last; int known[500]; known[0] = 2; known[1] = 3; int n_known = 2; for (i = start_at; i <= up_to; ) { printf("Looking for factors of %d\n", i); remainder = 1; last = 0; for (j = 2; ((!last) && (j < n_known)); ) { /* j is the index in our array of known primes. */ k = known[j]; /* k is a known prime number. */ printf("Trying %d..... ", k); remainder = i % k; if (!remainder) { printf("%d is a multiple of %d.\n", i, k); last = 1; /* No point continuing once we know we have not got a prime. */ } else { printf("%d is NOT a multiple of %d; remainder is %d.\n", i, k, remainder); }; if (k * k > i) { printf("%d is greater than the square root of %d.\n", k, i); last = 1; /* Every prime factor of a number must be smaller than the square root of that number; so we stop when we have exceeded that. */ }; if ((!remainder) || (k * k > i)) { last = 1; }; ++j; }; /* If the remainder is non-zero here, then we must have fallen out of the loop because we ran out of primes, or exceeded the square root, rather than because we rejected an obvious multiple. So, we can add i to our list of known primes. */ if (remainder) { printf("%d looks like a prime.\n", i); known[n_known++] = i; }; /* Now we move on to the next known non-multiple of 2 or 3 */ i += miss; miss = 6 - miss; /* If we just skipped 2, next time we must skip 4. If we just skipped 4, next time we must skip 2. */ }; printf ("Found %d prime numbers smaller than %d\n", n_known, up_to); for (i = 0; i < n_known; i++) { printf("%d ", known[i]); }; printf("\n"); return(0); };
/* Note this may well need to be modified to run all the way up to 10 figures. But that's no problem for a hacker:) */
The Bible says Jonah was eaten by a large fish. Everybody knows whales are mammals.
Beside which, the ark thing [Ge 6 et seq] is quite obviously fabrication. The ark is "300 cubits long x 50 cubits wide x 30 cubits high". A cubit is reckoned to be about 50cm. in modern measurements, so we're saying 150m. by 25m. by 15m. Which is big for a wooden ship, especially without metal reinforcement; but not very big for all the world's animal species. Getting the logistics to work, just so this boatload of people and animals could survive a massive wave of indiscriminate killing, would have required a whole lot more effort than just a simple targeted eradication. And then, after saving just two of each of those animals, he goes and sacrifices a bunch of them [Ge 8:20-21]. Also, before the flood there must have been no such thing as refraction [Ge 9:12-15]. (And after all this was over, Noah got pissed and fell asleep naked. His kids put a blanket over him and they ended up getting the blame).
Basically it reads like one of those awful, cheap movies where five minutes after watching it you realise it was based on a totally impossible premise. [If you managed to drill right to the centre of the Earth, gravity would be working against you between there and Australia. Molten gold solidifies from the bottom upwards, not from the top down. Objects made smaller by squashing matter into the empty space it contains would still weigh the same. A motion sensor held in the hand gives false positives. Et cetera ad nauseam.] Good enough fairy tale, if you can read it quickly without questioning {and some authors manage to inject enough pace into their work that you're too busy concentrating on the action to notice some quite blatant errors}; but too many reasons why it wouldn't work like that in real life. Of course, if you strip away the embroidery, you get "Some guy built himself a boat, then it started to piss down with rain; so he got in the boat with his family and all their animals. The water got deep enough for the boat to float, and it moved." That's believable.
Remember, kids, the Bible has three strands deftly interwoven: a historical account of life up to 6000 years ago; a fanciful mythology complete with plenty of sex and violence; and a sales pitch for the Jewish faith. It can be very hard to pick these strands apart; especially where a piece of mythology based on real fact is used as an advert for God.
OK, I'll hold up my hands and admit the initial comparison was a bit OTT. The point I was trying to make was, just because something is against the law doesn't mean it isn't going to happen. Think: under-age drinking, breaking speed limits, smoking pot, file-trading, &c. There's a whole world of lawlessness out there that Mr and Mrs Average-Bungalow can't even imagine..... nor do they need to, because most of it doesn't affect them.
Decompilers are not ready yet, but it would be foolish to pretend they never will be ready. A human can understand anything that a computer built by humans can understand.
Copying portions of closed-source software into open-source software would be subject to easy detection, since the copyright holder would have access to both lots of source code.
Copying portions of open-source software into open-source software is entirely the point of open-source software and is to be encouraged.
Copying portions of any software, whether open or closed source, into closed-source software is undetectable without committing a similar crime.
Anyway, why would any open-source developer want to "borrow" closed-source code? It would be akin to a famous seafood restaurant "borrowing" a supermarket's Own Brand Economy Value Range Ocean Pie recipe!
Except that UFS logging ("journalling") has been available since Solaris 7. It wasn't turned on by default, but a simple edit of/etc/vfstab is all that's needed.
Mud sticks is all I mean. Solaris used to write everything to disk {unless told not to}, Linux used to rely on not having power failures {but now ext3 fixes that}.
As for the rest of your claims, every piece of closed-source software I've seen specifically prohibits decompilation/disassembly.
Riiiiiight..... so a simple notice saying "DO NOT FLY AEROPLANES INTO THIS BUILDING" would have prevented 11/09/01 altogether?
From what little I've seen of Solaris, it seems that it's basically a Unix-like OS based around a monolithic kernel and conforming more to the System V way than the BSD way; but up to now it has been closed source.
The operating system on every PC I own is also a Unix-like OS based around a monolithic kernel and conforming more to the System V way than the BSD way. And it always has been, and always will be, Open Source.
AFAICT the main difference is that Solaris has earned itself the reputation for slowness by insisting to write everything to disk before saying ready, whilst Linux never writes anything to disk until one of the following happens: (a) a process asks for more memory and RAM is full of cached disk data. (b) shutdown. But default caching policy -- which almost certainly can be changed -- is no more an adequate criterion for judging an operating system than shoes are for judging a sexual partner.
I, for one, like to think I have some principles. I prefer manual methods over closed-source software. As it happens, I have reached a position where I can exert some influence: I instituted an almost total GNU/Linux migration in the company where I work There is only one department which is still using Windows, and that's accounts -- for reasons beyond my control, namely to be compatible with Group Head Office's legacy systems. I can't be the only idealistic young IT manager in the world. As awareness of Open Source -- and its benefits -- grows, closedness of source is becoming a criterion for rejecting a software product.
But the real point runs much, much deeper. Sun aren't stupid.
Closed source, however much its proponents bluster, is going to become a thing of the past soon anyway. Remember it was James Watt who put one of the nails in the coffin of Slavery. Sometimes, a technology comes along that enables, or even forces, great political change. Decompilers are going to kick off big-style any time soon, and will do for closed source what steam engines and electric motors . The problems of decompilation are, mathematically, very similar to those of shape recognition (and the US authorities are spunking their pants over systems claimed to be able to recognise a face in a crowd from a photograph taken from a different angle; it's Not Quite There Yet though). Now, I can buy something barely half the size of a DVD box that can decipher my handwriting -- and it does so using just a piddly little low-power RISC processor. Scale up the power a lot, and re-render the image..... it's surely a matter of tick-tocks before someone has a workable decompiler together. OK, so you might not get back your variable and function names, unless the compiler left them kicking around some spare blocks at the end of the binary; but these are things we can put up with.
Like it or not, in a few years' time, all software, to all intents and purposes, will be open source. And Sun know they're better off inside the tent pissing out, than outside the tent getting pissed on.
OK, I finally figured out how to get Slashdot to do proper indentation..... so here is the SpamJavelin code. Put the following between the <HEAD> and </HEAD> tags:
Now where you want an e-mail address to appear, put the following code:
<? sj("myname@mypatch.myisp.co.uk") ?>
I'm sure I could have optimised it to run faster but then it would have been less obvious what it was doing, and maybe less instructive. This code is in the public domain, because I don't believe the licence should outweigh the work it protects.
Virtual Hosting is what I use, and I give everybody a slightly different version of my e-mail address. I make no attempt to disguise it, either; I gave my address to you for your use, not so you could pass it on to all and sundry. If you have a virtual mail host and a web site, then try SpamJavelin for disposable address generation. It adds trace digits to your e-mail address when it is displayed, which give you the time, date and IP address through which it was harvested. If your ADSL is stable enough that you dare to point an MX record into your home (or you work for an ISP), you could even go one further and create entire disposable subdomains.
I think wider adoption of SMTP authentication would make a dent in the spam problem. Sendmail isn't the easiest piece of software in the world to configure, but it manages auth quite well once it's set up. Suppose some big ISP such as Wanadoo decided to insist one day that SMTP mail originating from non-SMTP-auth servers would not be welcome on their POP3 servers?
I have the right to run an SMTP server; but at the end of the day, nobody is obliged to take any notice of what comes out of it. It's their inbox, not mine. I have the right to run BIND, but my name records won't automatically be picked up by the outside world.
Maybe we need the various NICs of the world -- or some nwe, analogous National authorities -- to thrash out a set of rules for getting a server listed as being OK to accept mail from? The only alternative is going to be to create closed, private networks; but such a system would likely be highly fragmentated.
My question is, will it allow you to run any damn thing you like -- even stuff that came in from an overflowing buffer -- on a processor with native hardware NX support?
Copy prevention which permits legitimate use whilst denying "other" uses is impossible. Not just supremely difficult, actually impossible. That is not a limitation of present technology that will be resolved by a sufficiently clever invention; it is a limitation of the Universe, like nothing being able to exceed the speed of light or a system never being able to put out more energy than is being supplied to it. Human beings will walk naked upon the surface of the Sun before copy-prevention is made to work.
The Secure Player is designed to render digitally-encrypted content into a form that humans can appreciate. In other words, analogue audio and video. Such signals can always be copied and re-recorded in an unencrypted form, and there is no way for the Player to be certain what is happening downstream of itself. Any form of distortion applied to the signal in a blanket attempt to prevent recording must be imperceptible to humans watching the signal. Any attempt to detect the presence of a recording device {time domain reflectometry?} can be defeated, since we have the advantage of knowing what measurements are being made.
PART TWO
The publishing industry -- and whether that be books, records, movies, CDs, videos or DVDs, the rules are the same -- has always depended for its very existence upon a simple idea: that the initial cost of the wherewithal to package-up content in a form that will be acceptable to consumers is great enough to prevent anybody from entering the industry. It should have been obvious that this situation would not persist forever. The moment that the printing-press had been invented, someone had already begun work on making a portable version.
Now let us compare and contrast the situation of the publishing industry with two other almost universally disliked industries: the fossil fuel industry, and the meat industry. The fossil fuel industry continues to extract coal and oil from the gaping wounds in the flesh of Mother Earth. One day there simply will not be any more oil or coal left down there. Even before that day dawns, there has to come a time when non-fossil fuels are the cheaper option. At least the meat industry has the foresight to breed enough animals to replace the rotting corpses upon which its supporters gorge themselves. There is nothing inherently unsustainable about feeding an animal and using its body to rearrange amino acids. With careful management, it is perfectly possible to obtain a supply of meat which is limited only by the amount of fodder available; and turning plants into burgers this way is less wasteful of resources than artificially texturising proteins (though it does rankle with the prevailing creed of mortality-denialism).
It is my contention that the publishing industry today is in the situation that the fossil fuel industry will face very soon. Everything that the publishing industry depended on for its business model to function has been annihilated. Today, the cost of the equipment required to manufacture DVDs, CDs, books and so forth is close to negligible, and entry into the market depends only on the willingness of customers to buy the wares you are selling.
PART THREE
Copyright violation is not the same as theft. If I steal a CD from a store, the store no longer has that CD to sell. If I make a copy of my friend's CD, my friend has their CD back once I am done. The store cannot sell that CD to me, because I already have another copy of it; but so what? There might be a million and one other reasons why a store might lose the ability to sell me a CD, not the least of which is that I might not even like it.
I see a CD recorder as being somewhat analogous to a breadmaker. I buy my own blank CD-Rs [flour, yeast, salt, sugar and water] and use my own effort, together with electricity I have paid for with money I earned by my own graft, to make bread for my consumption [CDs for me to listen to].
But being serious for a minute, look at it this way. Stuff done using closed-source software is a complete mystery. If anything goes wrong with that software, we can do nothing about it except take out our frustration on those we love most. What if the company that made the software goes out of business? Releases a new version that is totally incompatible with the old version? Stops making it altogether? All they are really interested in is wringing money out of their customers. If some customer's valuable data goes missing and they can't recover it, that's just too bad.
Doing it by hand is only just the first step in writing our own in-house replacement for closed-source software. Because we write it ourselves, we can customise it exactly to match the way we work.
For one thing, I -- and my company -- will never be beholden to faceless corporate interests who see me as no more than a walking wallet.
For another, I consider closed-source software to be the modern-day equivalent of slavery. If you're too poor to be able to afford to own a slave, and too white to be likely to be sold as a slave, does that mean you should not care? And, just as James Watt made probably the most significant contribution to the abolition of slavery, it will be a technologist who brings the closed-source infrastructure crashing down to bury the New Old Masters.
We used to use Slackware on our colo servers; but following an incident, which required a re-install of one machine, we were forced to make a choice between SuSE (which we'd have had to pay for) or Debian (which I already knew intimately). Easy decision (and made me less replaceable into the bargain)! I soon had my boss -- an old-skool Unix guru and Slackware devotee -- converted to the wonders of apt-get. (Till a package he wanted wasn't in apt, then he was back to cursing and decrying package management systems of all flavours. But this si normal.)
The colo machines are running Woody (stable), but in the office, I'm running Sarge (testing) and Sid (unstable) on my desktop, just because it includes the latest KDE. Usual story: needed just one package; tried backports, hit snags; decided what the hey. No problems as yet. Remember, Debian is always more stable than Fedora -- and packages won't get updated unless people actively test out the newest versions and give decent feedback. Also, in Debianese, "unstable" refers not to the behaviour of the software, but to the level of development activity. If you want a really unstable operating system from Debian, try experimental..... at home, not at work, and make sure you don't have any sharp objects within easy reach.....
To summarise, I recommend: Stable for remote servers; Testing for servers you can physically get to and other people's desktops to which you can get root access; and Unstable for your own desktop.
CD players aren't as smart as DVD players. The data on a CD is just unencrypted PCM audio. 16 bits per sample, 2 channels, 44100 samples a second. But back in the day when CDs were invented, nobody thought it was important to be able to lock out competitors from manufacturing compatible media and equipment. Indeed, the specification was published -- in a certain volume with a rather fetching scarlet cover, the title of which escapes me -- specifically in order to allow everyone to be able to make CDs and players. Yes, even Fred in the Shed, if he had a particularly-well-equipped shed.
The bad news is that the pits and lands do not correspond directly to zeros and ones, but the good news is that it's "just" "simple" cross-interleaved Reeds code, for error correction, and if you are supremely foolha^H^H^H^H^H^Hconfident, you can just parse the "data" bits from the "parity" bits and feed them into your DACs. But it's not hard to build a simple logic matrix that does the error detection and correction.
CD-ROM uses an ingenious modification, where some of the error-proofing bits are replaced by addressing bits. This gives 2048-byte sectors and also has the advantage that the error-correction will be so shot to pieces, that any decent decoder will just spit out all zeros -- which will sound like silence. (Don't attempt to verify this using headphones, since a badly-implemented decoder could produce anything from DC to full-volume static).
For DVD, other concerns (like the movie studios making as much money as possible whether or not it might be morally justifiable) prevailed over not treating the people who pay your wages like shit. So while the disc itself is based physically on the original HDCD specification, the data is unnecessarily munged. (For instance, the audio/video data on a movie DVD is encrypted; although the rightful owner of a DVD is automatically entitled to decrypt it, by virtue of ownership, and may use reasonable force in pursuit of that right, so it serves fuck-all purpose except making life awkward for the person in the street.) And it's possible that there might be the ability to upgrade firmware by having a certain named file on the DVD, though the details would vary from one make of machine to another. One would hope that a sanity-check would be performed on the data first, and then (and only then) would the firmware be upgraded -- ideally, also depending upon some deliberate action by the user.
And quite probably the same people who have problems with "broken coffee holders" or "lead too short on the foot pedal", or who add up spreadsheets with a calculator. Not to mention typing out their tables of contents by hand, before instructing an unsuspecting technician to add a sentence that just happened to overflow a page and arse up the TOC. Eventually I reduced the font size in the last paragraph just to keep it from throwing a page break. If I had done it properly, nobody would have learned anything (and I'd have had a bollocking for taking too long to do what was really a complex task that just looked simple). Plus, really properly would have required a 12-bore shotgun. As it was, I got a bollocking for spoiling the document (there was a sort of pattern to events in that job, see if you can spot it..... ), and some other poor sod had to deal with the TOC. Dunno if he used the shotgun or not though.
Let 'em breed for a few more generations and there will be Tipp-ex all over monitors.
I did something similar once; though it was a different -- and some would say more deadly -- Stasi unit that I was trying to bait. For a while, I had a file called "10yr_old.jpg" sitting in the anonymous download area of my FTP server. (It was actually a photograph of a glass of Scotch whisky.)
It perished, along with my record 370 day uptime, in the great forgetting-to-press-the-emergency-credit-on-the-el ectric-meter incident of 2002.
Around here, if you buy items to a lower value than the gift voucher, you get as much of your change as fits the available denominations in gift vouchers. Since the smallest unit is usually £1, that means that you will never be able to exchange more than 99p of gift voucher for cash. If you want to give someone an odd amount such as £35, you just give them one each of £20, £10 and £5, in the same card. Also, there is no expiry date on gift vouchers -- that would actually be illegal, since it would constitute a form of protection racket.
There isn't a lot of fraud you can do either. Gift vouchers are serialised, and someone somewhere is keeping track of which serial number was issued to which store. They are checked for authenticity by a human being -- generally harder to fool than a machine, because you can know exactly what a machine is looking for. Where there have been forgeries, the stores have known pretty well what they were up against. A small-time forger is probably going to make less of a dent in the finances than cumulative rounding error -- and a big-time forger will have much drier lentils to soak.
Sure there's a cost incurred in printing the vouchers, and distributing them securely, but no more the store can afford to swallow -- otherwise they wouldn't issue vouchers in the first place. Setting up the infrastructure for reusable gift cards also has its own costs. It's too much like tech for tech's sake.
Slashdot Mirror
I heard that, but my old Daewoo TV set doesn't like decoding text off my cable box {NTL, pace 4000 series}. It was never much cop decoding it off the air. I thought that could be to do with the fact that I live so far down in the bottom of a valley, I have to go uphill to get to the river!
In the TV's defence, however, it does use the same codeset as a Philips telly, and therefore my DVD recorder remote lets me adjust my TV volume (text is all but unusable, picture is set right, cable box usually changes station unless recording a movie off Sky). So I'm half happy at least.
About connecting two appliances to one SCART socket: it will only ever work if only one output device is ever switched on at a time. When an op-amp -- strictly, any class AB output stage -- is unpowered, its output is high-impedance {both transistors are off}. When it's powered and amplifying, its output is quite low-impedance and will happily sink any signal coming from the other output.
Hey, they don't even have proper colour in the USA! Things on the TV screen appear in colours as opposed to shades of grey, but the colour of the TV image usually is not the same as the colour of the real thing. That's the disadvantage of NTSC {where DC offsets tend to cause cumulative errors thanks to parasitic capacitances behaving as integrators} versus PAL {where errors due to DC offsets tend to cancel one another out very quickly, because the signal is inverted on every other line}. Also, the higher frequency PAL colour carrier allows for more bandwidth.
When we show the snooker on BBC2 -- and you have to watch the snooker if you've got a colour TV set, it's the law -- the table is green; there are fifteen red balls, and the coloured balls go: yellow, green, brown, blue, pink, black. In the States, to show a snooker match that anyone watching TV could understand, they would have to use a blue table, fifteen yellow balls, and the colours are orange, sky-blue, red, violet, creamy-white with little brown spots and black (which transmits fine). And there would be an advert break after every shot. Needless to say this does not help the players much. They tried showing pool on TV instead, but it was very disconcerting to be told the red player was winning when there appeared still to be seven reds on the table and the guy with the cue in his hand was taking aim at what appeared to be a yellow ball.
To modify Schneier's Law a little, anybody can write a piece of software so secure that they themself cannot crack it.
In the open source camp, nobody needs to write a JPEG viewer, because it's already been done once, and done right. Only the closed source crowd can't touch it, because we wrote it for everyone to share, not for some people to lock away. So they have to write their own, and they still get it wrong.
All the claimed faults with Windows really come down to one failing, and it isn't one that Microsoft is going to do anything about: No access to the source code. The only way to ever be certain what any piece of software does is by examining the source code.
I've run right out of sympathy for Windows users. If you are still running Windows after all this, you deserve everything that happens to you. Understand this one thing: Windows is never, ever going to get any better. It can't; because as long as good guys outnumber bad, closed source will always be less secure than open source. Cut your losses now and switch to a better operating system. You can live without your favourite Windows applications; but the longer you leave it, the harder it will get.
No, it's not just a threat. It's perjury on the MPAA's part {under US law}. It's also libel {under Aussie law} if the takedown notice was shown to an upstream ISP; otherwise {and probably even if so anyway} it's harassment occasioning distress or alarm* {under Aussie law}.
Unfortunately, libel is only a civil offence, so there can be no grounds for extradition. Which is a shame, because if the Australian legal system is anything like ours, the loser of a court case pays all court costs. But perjury is a crime in Australia, so the MPAA might be extraditable to Australia for that, and if harassment is a crime in the USA then they might also be extraditable on that count too. However, you can't extradite someone to be sentenced to a harsher penalty than they would face back home.
* That's actually a UK offence; I am guessing Australia has a similar one on its statute books.
A centrifugal switch does actually sound like a better way of doing it ..... unless there are other problems ..... You could emulate it perfectly, electronically, by having positional feedback, but it'd cost more than a simple delay switch.
..... I just like DC brushless motors!
I think DC brushless is still overall the best way to do it, though. (And you need positional feedback, which you get from Hall-effect or optical sensors, so you know the motor is going round). Especially polyphase -- which can even run without a permanent magnet, since the armature is always lining up between lines of flux. But then, I'm biased
Microsoft software is closed-source. As a consequence of this, the good guys (who vastly outnumber bad guys) are not allowed to look at the code and spot potential security holes, suggest fixes &c. Meanwhile, bad guys look at the code anyway, permission or not, spot the security holes and write software which takes advantage of them.
Symantec sell anti-virus software. This software is closed-source. As a consequence of this, everyone who wants a copy has to pay for it. Plus, the good guys (who outnumber the bad guys) are not allowed to examine and improve it; while the bad guys examine it anyway and take advantage of any opportunity to exploit it.
Symantec basically exploits the disadvantaged -- people who, through no fault of their own, have had something unpleasant happen to their computer -- for financial gain. If someone is running Windows, it's not really their fault that Windows is insecure. After all, it was already on the computer when they bought it (thanks to Microsoft's illegal monopoly), and it appeared to work out of the box.
Imagine if a restaurant sold food that made you constipated, knew that it made you constipated, and didn't do anything about it except suggest you buy some laxatives from the chemist across the street. Would anybody put up with that? It's crazy that in the realm of computers, people can and do get away with this sort of stuff all the time. I think it's all to do with how, in the late 1970s, someone at VisiCorp got worried in case someone designed a road bridge with the help of VisiCalc {a then-popular spreadsheet}, it collapsed, and VisiCorp got some of the blame.
The ONLY way you can ever be sure your software will do what you want, exactly what you want and nothing but what you want, is to read the source code -- or get somebody with nothing to gain from lying to you to do that for you. And if the supplier won't let you read the source code then screw them - they are no good.
I think you misread what I was talking about. What you say makes sense in its own right, but it doesn't have anything to do with what I said.
Unless you pull some stunts, a single phase induction motor will never start from rest, because the only thing magnetising the armature is the induced current due to the difference in rotational speeds between the armature itself and the "revolving field" (which, with just one set of windings, is more like a collapsing and expanding field). One solution is to use a "shade" (a single or double shorted turn of thick copper wire) on one pole piece to deliberately distort the magnetic field, and so give the armature an initial kick; but this makes the motor inefficient and so isn't practical for anything bigger than a few watts. Another, which doesn't introduce so many losses, is to use a second stator winding with pole pieces at 90 degrees to the first, and energise this with current 90 degrees out of phase with the first winding. Now you really do have a true revolving field -- and as a bonus, you have twice the magnetism available, which gives you extra torque (which you typically need at starting anyway). But, due to the fact that the electrical phase shift (due to the capacitor) is not exactly equal to the mechanical phase shift (due to the offset windings), this will introduce losses. Fortunately, once the motor is running, you can switch off one of the windings and it will carry on rotating.
In a manual-start application, it is easy to have a switch with "stop", "run" and "start" positions and spring-loaded so it will go from "start" to "run" when released. But in a thermostatically controlled application, you need a device to automatically apply power to the starter winding just for long enough that the motor catches, then disconnect it. Traditionally that device is a thermal relay (heater and bi-metallic strip). The heater is connected in parallel with the running winding. When cold, the bi-metallic strip is touching a contact that completes the circuit through the capacitor and starter winding. As the strip heats up, it bends away from the contact and disconnects the starter winding. However, if it is not getting hot enough to bend (due to low voltage; recall that P = E ** 2 / R, so a drop of 10% voltage means 20% less power), then it will stay connected. This means the starter winding will stay in circuit and the motor will overheat.
A thermal relay introduces a loss of its own, of course; but it's typically only a watt or so. If this is less than the loss due to having the motor run in split-phase mode full time, and less than the loss due to using shaded poles, it's still a saving.
The reason why conventional air conditioning units {and refrigerators -- a fridge is just a cupboard with its own air-con venting into the kitchen} are sensitive to voltage drops, is the kind of motor they use to drive the compressor; a capacitively-started induction motor. The idea is that once the motor has started, a time delay relay disconnects the starter winding. This time delay relay typically uses a simple bimetallic strip and heater coil arrangement; in pre-semiconductor times, this was about the only way to do it, and it just kind of stuck. At first, the strip is touching a contact which sends current through the capacitor and starter winding; as it heats up, it bends away from the contact and cuts the power to the starter winding, so only the main winding is powered. If you don't use the starter winding then the motor will sit still (unless you spin the armature by some external means).
..... and gets hotter than it should. Now, if the delay relay were mounted in good thermal contact with the motor, then it would be helped to operate by the excess heat building up in there; but that huge hefty chunk of a motor would slow down the resetting action. This means next time the refrigerator's thermostat is calling for cooling, the motor won't start because the delay relay is now in the "run" position. So the motor just gets hotter and hotter. And he fridge certainly isn't getting any cooler, so the thermostat won't open in a hurry. It has actually been known for fridges to fail castastrophically under low-voltage conditions!
The problem is that at low voltages, the heater doesn't get hot enough to open the bi-metallic switch. The starter winding stays connected all the time and the motor draws about double the power it should
(As an aside, I know that an electronic delay relay could be built that would do the same job, but using a simple R-C delay circuit coupled to a conventional electromagnetic relay, for about 50p in bulk. Maybe modern fridges do actually use this kind of thing instead.)
If you wanted to build an air conditioner that was really immune to supply fluctuations, the obvious choice would be a DC brushless motor. You could run it from mains via a switch mode supply -- they're cheap as chips nowadays -- or straight from DC. Brushless motors are quite tolerant of voltage variations anyway, as long as you can get enough whack to shift the spindle and not so much as to damage the transistors in the drive circuit. And it would also be an idea to give a refrigerator a chimney of its own, so as to dispose of the hot air it produces directly rather than relying on your home's aircon to shift it. If you added a nice big air relief opening, the draught thus created should help to cool the kitchen. In winter, you could divert the fridge flue into an upstairs room (you don't want to get it back anywhere near the fridge). With an aircon, you probably could do something sensible with the meltwater from the ice that builds up on the evaporator, too.
Exactly -- there are plenty of comments in all the config files, and the way Slackware startup works is easier for a n00b to understand than most Linux distros {in the same sort of way that 6502 machine code is easier for a n00b to understand than Z80 machine code, if that isn't showing my age}.
I started out with Debian, found it a bit awkward {I was fine at the command line, but X, which I wanted to get into, was an absolute mystery to me}; and went with Mandrake instead. It let me install both KDE and GNOME, plus a few other window managers just to be sure; I found KDE was my favourite. And I gradually twigged onto how the graphical tools were causing changes in the config files. By the time I knew I'd outgrown Mandrake, I was more confident about returning to Debian. Since then, I have played with Slackware, and I really do kind of like it; it's just that my Debian system really hasn't given me cause to think about moving on, and changing distros just for the sake of it would be a violation of the KISS principle that underlies Slackware.
But if Slackware gets something really cool that Debian doesn't, I'll certainly consider it seriously.
#include <stdio.h>
/* We implicitly eliminate all multiples of 2 and 3 by starting at 5, and
/* j is the index in our array of known primes. */
/* k is a known prime number. */ ..... ", k);
/* No point continuing once we know we have not got a prime. */
/* Every prime factor of a number must be smaller than the
/* If the remainder is non-zero here, then we must have fallen out of
/* Now we move on to the next known non-multiple of 2 or 3 */
/* If we just skipped 2, next time we must skip 4.
:) */
/* Sieve of Eratosthenes: a program to find prime numbers */
int main() {
int start_at = 5;
int up_to = 200;
int miss = 2;
alternately skipping 2 and 4. So, every number we look at is either
6n+1 or 6n+5. This is because;
6n = multiple of 2 and 3
6n+2 = even
6n+3 = multiple of 3
6n+4 = even */
int remainder, i, j, k, last;
int known[500];
known[0] = 2;
known[1] = 3;
int n_known = 2;
for (i = start_at; i <= up_to; ) {
printf("Looking for factors of %d\n", i);
remainder = 1;
last = 0;
for (j = 2; ((!last) && (j < n_known)); ) {
k = known[j];
printf("Trying %d
remainder = i % k;
if (!remainder) {
printf("%d is a multiple of %d.\n", i, k);
last = 1;
}
else {
printf("%d is NOT a multiple of %d; remainder is %d.\n",
i, k, remainder);
};
if (k * k > i) {
printf("%d is greater than the square root of %d.\n", k, i);
last = 1;
square root of that number; so we stop when we have
exceeded that. */
};
if ((!remainder) || (k * k > i)) {
last = 1;
};
++j;
};
the loop because we ran out of primes, or exceeded the square root,
rather than because we rejected an obvious multiple. So, we can
add i to our list of known primes. */
if (remainder) {
printf("%d looks like a prime.\n", i);
known[n_known++] = i;
};
i += miss;
miss = 6 - miss;
If we just skipped 4, next time we must skip 2. */
};
printf ("Found %d prime numbers smaller than %d\n", n_known, up_to);
for (i = 0; i < n_known; i++) {
printf("%d ", known[i]);
};
printf("\n");
return(0);
};
/* Note this may well need to be modified to run all the way up to 10 figures.
But that's no problem for a hacker
The Bible says Jonah was eaten by a large fish. Everybody knows whales are mammals.
Beside which, the ark thing [Ge 6 et seq] is quite obviously fabrication. The ark is "300 cubits long x 50 cubits wide x 30 cubits high". A cubit is reckoned to be about 50cm. in modern measurements, so we're saying 150m. by 25m. by 15m. Which is big for a wooden ship, especially without metal reinforcement; but not very big for all the world's animal species. Getting the logistics to work, just so this boatload of people and animals could survive a massive wave of indiscriminate killing, would have required a whole lot more effort than just a simple targeted eradication. And then, after saving just two of each of those animals, he goes and sacrifices a bunch of them [Ge 8:20-21]. Also, before the flood there must have been no such thing as refraction [Ge 9:12-15]. (And after all this was over, Noah got pissed and fell asleep naked. His kids put a blanket over him and they ended up getting the blame).
Basically it reads like one of those awful, cheap movies where five minutes after watching it you realise it was based on a totally impossible premise. [If you managed to drill right to the centre of the Earth, gravity would be working against you between there and Australia. Molten gold solidifies from the bottom upwards, not from the top down. Objects made smaller by squashing matter into the empty space it contains would still weigh the same. A motion sensor held in the hand gives false positives. Et cetera ad nauseam.] Good enough fairy tale, if you can read it quickly without questioning {and some authors manage to inject enough pace into their work that you're too busy concentrating on the action to notice some quite blatant errors}; but too many reasons why it wouldn't work like that in real life. Of course, if you strip away the embroidery, you get "Some guy built himself a boat, then it started to piss down with rain; so he got in the boat with his family and all their animals. The water got deep enough for the boat to float, and it moved." That's believable.
Remember, kids, the Bible has three strands deftly interwoven: a historical account of life up to 6000 years ago; a fanciful mythology complete with plenty of sex and violence; and a sales pitch for the Jewish faith. It can be very hard to pick these strands apart; especially where a piece of mythology based on real fact is used as an advert for God.
- Decompilers are not ready yet, but it would be foolish to pretend they never will be ready. A human can understand anything that a computer built by humans can understand.
- Copying portions of closed-source software into open-source software would be subject to easy detection, since the copyright holder would have access to both lots of source code.
- Copying portions of open-source software into open-source software is entirely the point of open-source software and is to be encouraged.
- Copying portions of any software, whether open or closed source, into closed-source software is undetectable without committing a similar crime.
Anyway, why would any open-source developer want to "borrow" closed-source code? It would be akin to a famous seafood restaurant "borrowing" a supermarket's Own Brand Economy Value Range Ocean Pie recipe!From what little I've seen of Solaris, it seems that it's basically a Unix-like OS based around a monolithic kernel and conforming more to the System V way than the BSD way; but up to now it has been closed source.
..... it's surely a matter of tick-tocks before someone has a workable decompiler together. OK, so you might not get back your variable and function names, unless the compiler left them kicking around some spare blocks at the end of the binary; but these are things we can put up with.
The operating system on every PC I own is also a Unix-like OS based around a monolithic kernel and conforming more to the System V way than the BSD way. And it always has been, and always will be, Open Source.
AFAICT the main difference is that Solaris has earned itself the reputation for slowness by insisting to write everything to disk before saying ready, whilst Linux never writes anything to disk until one of the following happens: (a) a process asks for more memory and RAM is full of cached disk data. (b) shutdown. But default caching policy -- which almost certainly can be changed -- is no more an adequate criterion for judging an operating system than shoes are for judging a sexual partner.
I, for one, like to think I have some principles. I prefer manual methods over closed-source software. As it happens, I have reached a position where I can exert some influence: I instituted an almost total GNU/Linux migration in the company where I work There is only one department which is still using Windows, and that's accounts -- for reasons beyond my control, namely to be compatible with Group Head Office's legacy systems. I can't be the only idealistic young IT manager in the world. As awareness of Open Source -- and its benefits -- grows, closedness of source is becoming a criterion for rejecting a software product.
But the real point runs much, much deeper. Sun aren't stupid.
Closed source, however much its proponents bluster, is going to become a thing of the past soon anyway. Remember it was James Watt who put one of the nails in the coffin of Slavery. Sometimes, a technology comes along that enables, or even forces, great political change. Decompilers are going to kick off big-style any time soon, and will do for closed source what steam engines and electric motors . The problems of decompilation are, mathematically, very similar to those of shape recognition (and the US authorities are spunking their pants over systems claimed to be able to recognise a face in a crowd from a photograph taken from a different angle; it's Not Quite There Yet though). Now, I can buy something barely half the size of a DVD box that can decipher my handwriting -- and it does so using just a piddly little low-power RISC processor. Scale up the power a lot, and re-render the image
Like it or not, in a few years' time, all software, to all intents and purposes, will be open source. And Sun know they're better off inside the tent pissing out, than outside the tent getting pissed on.
OK, I finally figured out how to get Slashdot to do proper indentation ..... so here is the SpamJavelin code. Put the following between the <HEAD> and </HEAD> tags:
.= sprintf("%02X",$j);
<?
function spamjavelin($address, $link) {
global $HTTP_SERVER_VARS;
$alpha = "abcdefghjklmnpqrstuvwxyz1234567890";
$packed_ip = "";
$ip_array = split('\.', $HTTP_SERVER_VARS['REMOTE_ADDR']);
foreach ($ip_array as $i=>$j) {
$packed_ip
};
$packed_time = date("y") % 10 . $alpha[date("m")-1] . $alpha[date("d")-1]
. $alpha[date("H")-1]. date("i") . date("s");
list($user,$domain) = split("@", $address);
$new_address = $user . "-" . $packed_time . $packed_ip . "@" . $domain;
return($link ? "<A HREF = \"mailto:$new_address\">$new_address</A>" : $new_address);
};
function sj($address) {
echo spamjavelin($address,1);
};
?>
Now where you want an e-mail address to appear, put the following code:
<? sj("myname@mypatch.myisp.co.uk") ?>
I'm sure I could have optimised it to run faster but then it would have been less obvious what it was doing, and maybe less instructive. This code is in the public domain, because I don't believe the licence should outweigh the work it protects.
Virtual Hosting is what I use, and I give everybody a slightly different version of my e-mail address. I make no attempt to disguise it, either; I gave my address to you for your use, not so you could pass it on to all and sundry. If you have a virtual mail host and a web site, then try SpamJavelin for disposable address generation. It adds trace digits to your e-mail address when it is displayed, which give you the time, date and IP address through which it was harvested. If your ADSL is stable enough that you dare to point an MX record into your home (or you work for an ISP), you could even go one further and create entire disposable subdomains.
I think wider adoption of SMTP authentication would make a dent in the spam problem. Sendmail isn't the easiest piece of software in the world to configure, but it manages auth quite well once it's set up. Suppose some big ISP such as Wanadoo decided to insist one day that SMTP mail originating from non-SMTP-auth servers would not be welcome on their POP3 servers?
I have the right to run an SMTP server; but at the end of the day, nobody is obliged to take any notice of what comes out of it. It's their inbox, not mine. I have the right to run BIND, but my name records won't automatically be picked up by the outside world.
Maybe we need the various NICs of the world -- or some nwe, analogous National authorities -- to thrash out a set of rules for getting a server listed as being OK to accept mail from? The only alternative is going to be to create closed, private networks; but such a system would likely be highly fragmentated.
My question is, will it allow you to run any damn thing you like -- even stuff that came in from an overflowing buffer -- on a processor with native hardware NX support?
PART ONE
Copy prevention which permits legitimate use whilst denying "other" uses is impossible. Not just supremely difficult, actually impossible. That is not a limitation of present technology that will be resolved by a sufficiently clever invention; it is a limitation of the Universe, like nothing being able to exceed the speed of light or a system never being able to put out more energy than is being supplied to it. Human beings will walk naked upon the surface of the Sun before copy-prevention is made to work.
The Secure Player is designed to render digitally-encrypted content into a form that humans can appreciate. In other words, analogue audio and video. Such signals can always be copied and re-recorded in an unencrypted form, and there is no way for the Player to be certain what is happening downstream of itself. Any form of distortion applied to the signal in a blanket attempt to prevent recording must be imperceptible to humans watching the signal. Any attempt to detect the presence of a recording device {time domain reflectometry?} can be defeated, since we have the advantage of knowing what measurements are being made.
PART TWO
The publishing industry -- and whether that be books, records, movies, CDs, videos or DVDs, the rules are the same -- has always depended for its very existence upon a simple idea: that the initial cost of the wherewithal to package-up content in a form that will be acceptable to consumers is great enough to prevent anybody from entering the industry. It should have been obvious that this situation would not persist forever. The moment that the printing-press had been invented, someone had already begun work on making a portable version.
Now let us compare and contrast the situation of the publishing industry with two other almost universally disliked industries: the fossil fuel industry, and the meat industry. The fossil fuel industry continues to extract coal and oil from the gaping wounds in the flesh of Mother Earth. One day there simply will not be any more oil or coal left down there. Even before that day dawns, there has to come a time when non-fossil fuels are the cheaper option. At least the meat industry has the foresight to breed enough animals to replace the rotting corpses upon which its supporters gorge themselves. There is nothing inherently unsustainable about feeding an animal and using its body to rearrange amino acids. With careful management, it is perfectly possible to obtain a supply of meat which is limited only by the amount of fodder available; and turning plants into burgers this way is less wasteful of resources than artificially texturising proteins (though it does rankle with the prevailing creed of mortality-denialism).
It is my contention that the publishing industry today is in the situation that the fossil fuel industry will face very soon. Everything that the publishing industry depended on for its business model to function has been annihilated. Today, the cost of the equipment required to manufacture DVDs, CDs, books and so forth is close to negligible, and entry into the market depends only on the willingness of customers to buy the wares you are selling.
PART THREE
Copyright violation is not the same as theft. If I steal a CD from a store, the store no longer has that CD to sell. If I make a copy of my friend's CD, my friend has their CD back once I am done. The store cannot sell that CD to me, because I already have another copy of it; but so what? There might be a million and one other reasons why a store might lose the ability to sell me a CD, not the least of which is that I might not even like it.
I see a CD recorder as being somewhat analogous to a breadmaker. I buy my own blank CD-Rs [flour, yeast, salt, sugar and water] and use my own effort, together with electricity I have paid for with money I earned by my own graft, to make bread for my consumption [CDs for me to listen to].
But being serious for a minute, look at it this way. Stuff done using closed-source software is a complete mystery. If anything goes wrong with that software, we can do nothing about it except take out our frustration on those we love most. What if the company that made the software goes out of business? Releases a new version that is totally incompatible with the old version? Stops making it altogether? All they are really interested in is wringing money out of their customers. If some customer's valuable data goes missing and they can't recover it, that's just too bad.
Doing it by hand is only just the first step in writing our own in-house replacement for closed-source software. Because we write it ourselves, we can customise it exactly to match the way we work.
For one thing, I -- and my company -- will never be beholden to faceless corporate interests who see me as no more than a walking wallet.
For another, I consider closed-source software to be the modern-day equivalent of slavery. If you're too poor to be able to afford to own a slave, and too white to be likely to be sold as a slave, does that mean you should not care? And, just as James Watt made probably the most significant contribution to the abolition of slavery, it will be a technologist who brings the closed-source infrastructure crashing down to bury the New Old Masters.
Yes.
We used to use Slackware on our colo servers; but following an incident, which required a re-install of one machine, we were forced to make a choice between SuSE (which we'd have had to pay for) or Debian (which I already knew intimately). Easy decision (and made me less replaceable into the bargain)! I soon had my boss -- an old-skool Unix guru and Slackware devotee -- converted to the wonders of apt-get. (Till a package he wanted wasn't in apt, then he was back to cursing and decrying package management systems of all flavours. But this si normal.)
..... at home, not at work, and make sure you don't have any sharp objects within easy reach .....
The colo machines are running Woody (stable), but in the office, I'm running Sarge (testing) and Sid (unstable) on my desktop, just because it includes the latest KDE. Usual story: needed just one package; tried backports, hit snags; decided what the hey. No problems as yet. Remember, Debian is always more stable than Fedora -- and packages won't get updated unless people actively test out the newest versions and give decent feedback. Also, in Debianese, "unstable" refers not to the behaviour of the software, but to the level of development activity. If you want a really unstable operating system from Debian, try experimental
To summarise, I recommend: Stable for remote servers; Testing for servers you can physically get to and other people's desktops to which you can get root access; and Unstable for your own desktop.
CD players aren't as smart as DVD players. The data on a CD is just unencrypted PCM audio. 16 bits per sample, 2 channels, 44100 samples a second. But back in the day when CDs were invented, nobody thought it was important to be able to lock out competitors from manufacturing compatible media and equipment. Indeed, the specification was published -- in a certain volume with a rather fetching scarlet cover, the title of which escapes me -- specifically in order to allow everyone to be able to make CDs and players. Yes, even Fred in the Shed, if he had a particularly-well-equipped shed.
The bad news is that the pits and lands do not correspond directly to zeros and ones, but the good news is that it's "just" "simple" cross-interleaved Reeds code, for error correction, and if you are supremely foolha^H^H^H^H^H^Hconfident, you can just parse the "data" bits from the "parity" bits and feed them into your DACs. But it's not hard to build a simple logic matrix that does the error detection and correction.
CD-ROM uses an ingenious modification, where some of the error-proofing bits are replaced by addressing bits. This gives 2048-byte sectors and also has the advantage that the error-correction will be so shot to pieces, that any decent decoder will just spit out all zeros -- which will sound like silence. (Don't attempt to verify this using headphones, since a badly-implemented decoder could produce anything from DC to full-volume static).
For DVD, other concerns (like the movie studios making as much money as possible whether or not it might be morally justifiable) prevailed over not treating the people who pay your wages like shit. So while the disc itself is based physically on the original HDCD specification, the data is unnecessarily munged. (For instance, the audio/video data on a movie DVD is encrypted; although the rightful owner of a DVD is automatically entitled to decrypt it, by virtue of ownership, and may use reasonable force in pursuit of that right, so it serves fuck-all purpose except making life awkward for the person in the street.) And it's possible that there might be the ability to upgrade firmware by having a certain named file on the DVD, though the details would vary from one make of machine to another. One would hope that a sanity-check would be performed on the data first, and then (and only then) would the firmware be upgraded -- ideally, also depending upon some deliberate action by the user.
And quite probably the same people who have problems with "broken coffee holders" or "lead too short on the foot pedal", or who add up spreadsheets with a calculator. Not to mention typing out their tables of contents by hand, before instructing an unsuspecting technician to add a sentence that just happened to overflow a page and arse up the TOC. Eventually I reduced the font size in the last paragraph just to keep it from throwing a page break. If I had done it properly, nobody would have learned anything (and I'd have had a bollocking for taking too long to do what was really a complex task that just looked simple). Plus, really properly would have required a 12-bore shotgun. As it was, I got a bollocking for spoiling the document (there was a sort of pattern to events in that job, see if you can spot it ..... ), and some other poor sod had to deal with the TOC. Dunno if he used the shotgun or not though.
Let 'em breed for a few more generations and there will be Tipp-ex all over monitors.
I did something similar once; though it was a different -- and some would say more deadly -- Stasi unit that I was trying to bait. For a while, I had a file called "10yr_old.jpg" sitting in the anonymous download area of my FTP server. (It was actually a photograph of a glass of Scotch whisky.)
l ectric-meter incident of 2002.
It perished, along with my record 370 day uptime, in the great forgetting-to-press-the-emergency-credit-on-the-e
Around here, if you buy items to a lower value than the gift voucher, you get as much of your change as fits the available denominations in gift vouchers. Since the smallest unit is usually £1, that means that you will never be able to exchange more than 99p of gift voucher for cash. If you want to give someone an odd amount such as £35, you just give them one each of £20, £10 and £5, in the same card. Also, there is no expiry date on gift vouchers -- that would actually be illegal, since it would constitute a form of protection racket.
There isn't a lot of fraud you can do either. Gift vouchers are serialised, and someone somewhere is keeping track of which serial number was issued to which store. They are checked for authenticity by a human being -- generally harder to fool than a machine, because you can know exactly what a machine is looking for. Where there have been forgeries, the stores have known pretty well what they were up against. A small-time forger is probably going to make less of a dent in the finances than cumulative rounding error -- and a big-time forger will have much drier lentils to soak.
Sure there's a cost incurred in printing the vouchers, and distributing them securely, but no more the store can afford to swallow -- otherwise they wouldn't issue vouchers in the first place. Setting up the infrastructure for reusable gift cards also has its own costs. It's too much like tech for tech's sake.