Great Internet Media Plumbing Supply spokeperson Bob Haldeman announced that today, the 33 1/3rd anniversary of the Watergate breakin, that Sony's Label Gate media format could easily be cracked with a small shell script, or by typing Control-Alt-Meta-Cokebottle twice into the Sony Windows tool.
First of all, corporations are a creation of the state, so they only have the rights the state gives them when it charters them -- if people don't like the set of rights and privileges that corporate structure gives them, they don't have to incorporate, but operate under different structures, such as partnerships. (You'll notice that most law firms and many accounting firms aren't corporations - they're partnerships of various sorts.)
Regulated monopolies are a very special type of corporation - they've convinced the state to forbid other companies to compete with them, and to give them lots of other special status, in return for regulation to limit their activities in ways that ostensibly protect the public from abuse of the monopoly. Restrictions on their use of customer data are a reasonable and highly appropriate restriction, and if Verizon doesn't like it, they can see if they can get the state to let them out of the regulations in return for giving up their monopoly status - fat chance they'll go for that. Or they can threaten to sell their phone company monopoly territory to other people.
I've spent most of my career working for various parts of The Phone Company (not Verizon...), and my view is that the whole "natural monopoly" theory that was invented to justify granting regulated monopoly status was a total crock, and that Theodore Vail, the robber baron who got the Bell System into its dominant monopoly status, could have done better things with his life and his company, and the US (and indirectly, the rest of the world), would have been able to do much more technical innovation if the phone companies and radio broadcasting quasi-monopolies hadn't been done. Needless to say, this is not my employer's official opinion, except for the approximately one three-millionth of them that I own:-)
Bathtubs, shelf space, lack of hurry
on
War of Honor
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· Score: 3, Interesting
For reading by the fire on a rainy day, yes, a hardback book and some Scotch is really nice. But for reading escape fiction in the bathtub, paperback is really a much better choice. (For you non-lazy people, for reading while you're on the exercise bike, hardback is too heavy, though sometimes trade paperbacks have bigger print, which also helps.) The more interesting tradeoff is the higher-quality-printing trade paperbacks.
Shelf space is another real advantage of paperback books for fiction - they take about half as much space as hardbacks or big paperback computer books. If you read a lot, this can be an important constraint, unless you also dispose of books after reading them.
Besides, how much of a hurry are you in? There are *lots* of books out there to read. For most science fiction, my usual tradeoff is used vs. new, though I have the advantage of living near bookstores with large collections of used science fiction. There are a few authors I'll buy new the minute they hit the store (Steven Brust, Neil Stephenson, and this gradually became the case for the Honor Harrington series, though not for Weber's other books), but I'm very seldom in enough of a hurry to read a specific book that I'll buy non-remaindered hardbacks - the three I see on my shelves are Steven Brust's "Dragon", Vinge's "A Deepness in the Sky", and of course Cryptonomicon (but as a Cypherpunk, that was an obvious must-buy.) The 25th century and the quasi-Middle-Ages can wait an extra six months.
No, but while you probably need more total air conditioning if you split between two buildings, you need only about half as much space per building as you did before, because you're putting about half the stuff in each. So instead of one building with N square meters of server rooms and another building with N square meters of cheap low-quality graduate student desk space (:-), you need two buildings, each one with N/2 square meters of computers and N/2 square meters of desks. Obviously some pieces of equipment can't be split, so you have to decide how badly you need two of them for reliability - but for almost everything in the computer business, prices are much lower than in past years, comparable to expensive physics or chemistry equipment (which is more likely to catch fire.)
While it's too bad that the equipment was lost, and much worse that data was lost, one advantage of replacing old computers with new ones is that the same amount of computer capacity will cost you less money with new equipment, and will use less floor space, electricity, and air conditioning, and will cost less to maintain than the old equipment. Depending on your campus wiring infrastructure, it may be possible to take advantage of some other new architectural developments, like peer-to-peer storage. It's not just for pirate music - the cost of PC data storage is almost down to $1000 per terabyte, and some of the applications can be reliable enough to use it effectively.
Some companies run their own backup data centers, some use backup / disaster recovery vendors, some don't. It varies a lot by customer and industry. Another strategy that's been emerging rapidly is the use of Internet colo centers as backup sites (primarily the rackspace-oriented colo rather than managed hosting colo.) Engineering companies and companies that formed from mergers of similarly-sized companies often have two data centers anyway, so they'll use one to back up the other.
The big value of many of the disaster recover vendors, beside consulting skills, was traditionally that they owned mainframes, and assuming not too many people had disasters at the same time, they could mount your data on their mainframe without you having to spend a few million dollars to buy a spare mainframe - so they were basically selling part-time use of the mainframes. Transaction-based online services companies could sometimes live with this kind of environment, but not usually - if it takes a day to rebuild your database from backup tapes and journalling, that's probably ok for a manufacturing company, and maybe ok for a traditional bank, but it's a total disaster for an airline ticket sales system or an online stockbroker; even a couple of hours may be too expensive. So those companies often have to run their own backup sites, or at the very least will have a dedicated backup mainframe at the backup vendor.
One of the interesting technologies that's starting to affect this business is metropolitan-distance fiber optics for Storage Area Networks. Somebody else mentioned iSCSI, but for the mainframe world, Fibre Channel lets you connect processors and disk farms at distances up to about 30km, and for real computers (:-) Gigabit Ethernet on fiber also has a long range (and eventually 10gigE will be mature.) This is especially useful in some niche markets - Wall Street trading and banking firms can put disk farms in New Jersey, partly for physical diversity and partly for real estate cost reasons. They're also good for other downtown/suburban connections. Sometimes these are managed by the customer, but the internet data center business and local fiber providers are going hog-wild trying to sell this. (I work for AT&T, which is selling this.)
Halon is heavier than air, so if you're somewhere there's been a Halon dump, DO NOT HIT THE GROUND! Walk/run as upright as you comfortably can. The usual "stay low" advice is because hot air and smoke are lighter than regular air, so the regular air stays near the floor.
Halon (or at least most of the Halons used for fire suppression; not sure about all of them) is non-toxic, though it'll get you a bit high, like nitrous oxide or most solvents, so being stuck in the stuff won't injure you quickly (except from flying objects that were blown around by the gas pressure.) However, it's no substitute for oxygen, and you'll probably be wanting some oxygen real soon now. If you can remember not to breathe in the stuff, try not to breathe deeply, because there's more oxygen left in your lungs than the stuff you'll be breathing in, and unfortunately, while your body can generally figure out not to breathe in water or hot smoke, it's not as good at realizing that near-room-temperature inert gases aren't very useful. Mostly, don't worry about it - find a safe door to run for and run for it, and do some deep breathing once you're outside, and try to close the door behind you.
Instead of putting all the computers in one building, put half of them in two buildings. The main cost difference is some extra real-estate preparation. And if you've got a multi-gigabit network, it's going to multiple buildings, so spread out your routers. Huge centralized computers were really useful back when mainframes were the size of dozens of refrigerators, but if you're using modern machines, they're either rack-mounted or pizza-boxes, and or else they're PC-shaped. But you've got multiples of them and can spread them around.
Just because there's a politician whose organization will be buying Microsoft products doesn't mean that he's making a decision for all of India, or even all of India's government, or banning the competition, or necessarily anything at all except that he's saying Thanks to Bill for recent donations.
The statement that India is a poor country that can't afford to develop its own operating systems is laughable, especially given the timing of that speech and the Simputer deployment at the same time; the Simputer folks have done some really interesting user interface work for dealing with multiple languages and varying literacy levels.
If a Finnish grad student can afford to develop an operating system, surely somebody in India can afford to do so as well, though the government may be far too disorganized and bureaucratic to do it well. But beyond that, India's had a long tradition of training university students in Unix operating systems, and with a few hundred million educated English-speaking Indians, many of whom know Unix, the assertion that India can't afford to develop its own software when it can have it for free is an insult to one of the country's big and growing industries. (It's been about 8 years since I've worked directly with Indian software companies, but at the time they knew SunOS / Solaris just as well as I did, and Sun's done a lot of development over in India since then.)
I'll echo some of Firewood's comments - it doesn't need a government sponsor, just a service provider willing to implement it and a convenient payment mechanism; Paypal is probably convenient enough. Oh, yeah, you also need customers. So you get an account deblau@cashmail.example.net, and everybody who sends you mail and isn't on your whitelist gets a reply saying "Deblau charges 10 cents for reading email messages, refundable for non-stupid messages. If you want me to read it, click here http://cashmail.example.net/payme?mesg=13213421 and paypal me a dime."
The good news is that almost all of the horrible things you suggest won't happen. The service it purports to charge for isn't "delivering email" (that would take govt intervention) - it's "getting *you* to read a message", and if you only use cashmail.example.net for all of your email, it;s not easily circumvented.
The bad news, of course, is that nobody really wants to pay to send email to you, so you won't get any, so you'll decide that this service probably isn't for you, won't buy it, and cashmail.example.net won't make any money offering it.
Then there's the ugly news - cashmail.example.net, failing to make money from regular customers, will start spamming other mail services with You! yes, You! can get PAID to READ EMAIL and it'll just go downhill from there, really fast:-)
Adam Back developed a system called "hash-cash", that instead of requiring actual digital cash payment per message, requires the sender to do some computation, for example for a mailbox server or delivery system. It's easy to do a small quantity of hashes, so you can send real messages through the system, but sufficiently difficult to do large quantities that spammers won't find it practical. (Unfortunately, mailing lists also have problems, but they can be whitelisted.)
The computations he used weren't interesting or useful, but were very easy to verify quickly. Basically, the person doing the computation tries a large number of strings, looking for one that has an MD5 hash where the first N bits match a required value, and in some versions the input string has to have a specific form also. Checking one hash is pretty quick, but finding an input value with the right values for N bits of output takes an average of 2**N tries, so it's easy to tune the system for the amount of crunching an average machine takes to get the result.
The structure of the computation means that spammers can't cheat, because it's easily verified, and if the message doesn't include a valid piece of hashcash, you toss the message, so refusing isn't practical.
A few years back, I was out in Colorado for the August meteors. One night I was out camping and got a good view of the early ones, and the main night of the shower I was floating in a hot spring outside of Steamboat. It's an idyllic and relaxing way to watch, and beats freezing the night away.
Seemed wimpy compared to last year
on
Meet The Leonids
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· Score: 2
I drove up Mt. Hamilton, east of San Jose, CA, to an area that would have been pretty dark except that the full moon was blazingly bright. There was a bit of haze, which the moon lit up as well, so only the brighter stuff showed. I'd guess that between 2am-3am we saw maybe 50-100, though we weren't counting. A few were quite impressive, but it wasn't anything like last year's amazing show. I'm not sure how much of this was because of the number of meteors going by and how much was because the moonlight made all of the dim ones invisible, while last year was dark enough we could see far more of the meteors that went by and better details on the ones we saw.
Here in San Francisco, we have lots of bike lanes. Would a Segway survive in a bike lane, or would they get run over by cars and also get run over by bicycles?
Cyclists older than first grade who ride on the sidewalk aren't safe - curb cuts, driveways, pedestrians, etc. are pretty dangerous, and cyclists are dangers to pedestrians. It's much safer for them to ride on the street, aggressively taking the middle of their lane, unless there's a bike lane available. Occasionally they'll get assaulted by cars (it's happened to me a few times), but then it cuts down on how often little old ladies stick umbrellas in their spokes.
That's an interesting idea. One of the big problems with Segway is that it costs a lot of money for something that doesn't offer a huge value. However, when you're talking about golf, a certain fraction of the market is about conspicuous consumption and doing things for fun, among people who have disposable income. So they might sell to either the golfers or to the courses, and for golfing, they really are superior to $300 electric scooters. How much does a basic golf cart cost, though?
Re:Hrm, isn't that John Gilmore's ISP?
on
As the Spam Turns
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· Score: 5, Interesting
Actually, you've hit a major irony, because Verio refuses to continue selling John Gilmore internet access. John was one of the members of The Little Garden internet access co-op (back before ISPs were common), which was businessified, then bought by Best, which was bought by Verio, which was bought by NTT.
According to the SETI@HOME stats page, SETI is running about 45 TFLOPS, which is slightly ahead of the Earth Simulator's 40 TFLOPS or the LANL 10 TFLOPS machines. This isn't real precise - Top500 uses Linpack as their benchmark, which is a lot more realistic and controlled than SETI, so your mileage may vary. And of course that's Today's measurement from SETI, which is fairly variable in its CPU speed.
If you were watching a grainy pre-release bootleg video tape of The Last Starfighter, you were missing some of the best stuff in the movie. It's been long enough since I saw the movie that I don't remember _which_ Cray they used - I think it was the XMP - but they burned more CPU than just ab out anything else to date, and the graphics really rocked, at least by the standards of the day. Sure, you can do better on your $2000 desktop today, but you've got more CPU and lots more memory:-)
I also enjoyed the movie itself, but then I expected a B movie.
Why we keep getting these bugs
on
Due Diligence?
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· Score: 2
The ISS folks send out their periodic newsletter about new vulnerabilities. It's pretty depressing, not just because the number of bugs - but because most of them are the SAME BUGS - BUFFER OVERFLOWS. How long have buffer overflows been a known security risk? Why are we still putting up with them?
They were certainly well-known when I was in college in the mid 70s, but the PL/C dialect of the PL/I checkout compiler corrected mistakes like that at run-time. (OK, it often fixed them incorrectly, but at least least it wouldn't overrun an array.) And our professors dinged us for writing programs where that happened, and made us run the programs on input decks that were maliciously designed to check for programs that overflowed their buffers.
They were certainly well-known when K&R wrote their books on C which warned you to be careful about bounds checking when using pointers and arrays.
They were certainly well-known in the early 80s when everybody started complaining that the gets() and scanf() routines made it easy to overrun buffers on input when you weren't doing it by hand.
They were certainly well-known in the late 80s when the Morris Worm wandered around a lot of the machines in the internet.
They were certainly well known when the C++ string-handling libraries were designed to NOT overrun buffers, and when Java was designed to not even have pointers, and had array objects that checked bounds for you.
There are enough software engineering CASE tools that try to find problems more complex than lint() looks for, though perhaps array bounds checking isn't something they check effectively.
I like C - I really like it. It's time to stop using it. It's time to stop shipping code that has array bounds problems, and security code that hasn't been proofread for them. And it's time to stop using programs that run as root when they don't need to. This isn't the 80s any more.
There are other bugs out there - a popular attack is to try to abuse dotdots in path names, which there's more excuse for forgetting to check, and there are things like race conditions that are genuinely hard to check for (e.g. what happens when somebody's ripping up your temp files while your program is running), though checking return codes on system calls and doing something appropriate about failures is a good start.
If you're running a desktop machine, then yes, you'll burn more power using CPUburner@Home than not using it. The typical concerns that businesses have had are usually "but you're using *our* computer resources for *somebody else's* project" (not that they mind that gorgeous fractal-growing screensaver) or perhaps security or computer support, but usually if you explain it nicely, and if it's one of the non-commercial versions, as opposed to the "win prizes running your boss's computer" or "let us resell your spare cycles in return for nothing much" projects.
However, if your computer is a laptop that you run on batteries for a significant fraction of the time, be careful - NiMH batteries really don't like to power CPU-burners, and as they age, they tend to fail in ugly ways. I used to have a one-hour train commute, and my laptop simply did *not* like running GIMPS. Also, even if I turned it off when I was running on batteries, it slowed down the recharge process significantly when I plugged back in again, and I don't think it liked that either.
Seals make breathing holes in the ice. Both for the people and the bears, the standard method of hunting seals is to hang out near the breathing holes and grab the seals when they come up for air. As ice melt increases the open water, the seals have much more open space to breathe in, and hunting them becomes impossible. They're a major food source for the bears, and also for any people doing native subsistence hunting. Fishing is more possible if there's open water, but difficult. The people also do some bear hunting for food, and as the number of seals decreases, the people will probably do more bear hunting, greatly increasing pressure on the bears.
I'm also surprised, but remember that this device is limited by the PCI bus, while RAIDed disk drives at full crank may use enough bandwidth that somebody bothered inventing Ultra-Wide-160 SCSI instead of Wide-80 or whatever the previous generation of SCSI was. So it's slower than the RAM can do, but still faster than the disk drive. The real comparison is for applications that are affected by latency, not throughput, because that's what these things are great for.
It might be possible to build a device like this that's more cost-effective than system RAM, though this one isn't priced that way. You're trading the cost of a board for the ability to use cheapo PC100 or PC133 memory instead of PC2100DDR or whatever the latest and most expensive stuff is, and if you're careful, you can design it so it's not subject to the same memory limitations that the motherboard is, though that may be difficult with a 32-bit PCI bus. It'd be faster if it ran off the AGP bus instead of PCI, but that limits the applications to servers with slow or no video adapters, while PCI is probably good enough for most users who may want this to accelerate their graphics applications as well.
Remember how slow disk drives were 10-20 years ago? None of this 15000rpm, you were lucky to get 3600. And the seek times weren't 4ms, they were often 85ms for a full swing. Clever disk scheduling could let you optimize the way you used it, and RAID let you amortize it in different ways, but fundamentally you had to wait for mechanical stuff to slop around before you could read or write anything. (A decade or so ago, Margo Seltzer did a Usenix paper on disk scheduling that showed that rotational latency had started to be more important than seek time, which was a surprising change for most of us...)
This gives you your bits right now, and they were just marvellous as journalling accelerators for databases or NFS filesystems.
Dude - it's not there just to give your machine more RAM, it's there to be much much faster than your disk drive. The speedup isn't because it can push data a bit faster than SCSI can - it's because real disk drives have ~8ms seek times and ~8ms rotational delays, so the number of separate items of data you can write to your disk are limited by how fast the disk spins around and the heads slide back and forth, not by how fast it can pump data once it's in the right place. It *would* be nice if the motherboard could handle more memory, but for this application, large quantities of cheap memory are just fine, and you can save your northbridge and AGP port for stuff that needs to be fast.
Slashdot Mirror
Tokyo, October 17, 2005:
Great Internet Media Plumbing Supply spokeperson Bob Haldeman announced that today, the 33 1/3rd anniversary of the Watergate breakin, that Sony's Label Gate media format could easily be cracked with a small shell script, or by typing Control-Alt-Meta-Cokebottle twice into the Sony Windows tool.
Regulated monopolies are a very special type of corporation - they've convinced the state to forbid other companies to compete with them, and to give them lots of other special status, in return for regulation to limit their activities in ways that ostensibly protect the public from abuse of the monopoly. Restrictions on their use of customer data are a reasonable and highly appropriate restriction, and if Verizon doesn't like it, they can see if they can get the state to let them out of the regulations in return for giving up their monopoly status - fat chance they'll go for that. Or they can threaten to sell their phone company monopoly territory to other people.
I've spent most of my career working for various parts of The Phone Company (not Verizon...), and my view is that the whole "natural monopoly" theory that was invented to justify granting regulated monopoly status was a total crock, and that Theodore Vail, the robber baron who got the Bell System into its dominant monopoly status, could have done better things with his life and his company, and the US (and indirectly, the rest of the world), would have been able to do much more technical innovation if the phone companies and radio broadcasting quasi-monopolies hadn't been done. Needless to say, this is not my employer's official opinion, except for the approximately one three-millionth of them that I own :-)
Shelf space is another real advantage of paperback books for fiction - they take about half as much space as hardbacks or big paperback computer books. If you read a lot, this can be an important constraint, unless you also dispose of books after reading them.
Besides, how much of a hurry are you in? There are *lots* of books out there to read. For most science fiction, my usual tradeoff is used vs. new, though I have the advantage of living near bookstores with large collections of used science fiction. There are a few authors I'll buy new the minute they hit the store (Steven Brust, Neil Stephenson, and this gradually became the case for the Honor Harrington series, though not for Weber's other books), but I'm very seldom in enough of a hurry to read a specific book that I'll buy non-remaindered hardbacks - the three I see on my shelves are Steven Brust's "Dragon", Vinge's "A Deepness in the Sky", and of course Cryptonomicon (but as a Cypherpunk, that was an obvious must-buy.) The 25th century and the quasi-Middle-Ages can wait an extra six months.
It looks like NTK is out of their "I got £80million in venture capital for my .com idea and all I have left is this lousy t-shirt" T-shirts by now.
While it's too bad that the equipment was lost, and much worse that data was lost, one advantage of replacing old computers with new ones is that the same amount of computer capacity will cost you less money with new equipment, and will use less floor space, electricity, and air conditioning, and will cost less to maintain than the old equipment. Depending on your campus wiring infrastructure, it may be possible to take advantage of some other new architectural developments, like peer-to-peer storage. It's not just for pirate music - the cost of PC data storage is almost down to $1000 per terabyte, and some of the applications can be reliable enough to use it effectively.
probably not the best behaviour for a space ship.
The big value of many of the disaster recover vendors, beside consulting skills, was traditionally that they owned mainframes, and assuming not too many people had disasters at the same time, they could mount your data on their mainframe without you having to spend a few million dollars to buy a spare mainframe - so they were basically selling part-time use of the mainframes. Transaction-based online services companies could sometimes live with this kind of environment, but not usually - if it takes a day to rebuild your database from backup tapes and journalling, that's probably ok for a manufacturing company, and maybe ok for a traditional bank, but it's a total disaster for an airline ticket sales system or an online stockbroker; even a couple of hours may be too expensive. So those companies often have to run their own backup sites, or at the very least will have a dedicated backup mainframe at the backup vendor.
One of the interesting technologies that's starting to affect this business is metropolitan-distance fiber optics for Storage Area Networks. Somebody else mentioned iSCSI, but for the mainframe world, Fibre Channel lets you connect processors and disk farms at distances up to about 30km, and for real computers (:-) Gigabit Ethernet on fiber also has a long range (and eventually 10gigE will be mature.) This is especially useful in some niche markets - Wall Street trading and banking firms can put disk farms in New Jersey, partly for physical diversity and partly for real estate cost reasons. They're also good for other downtown/suburban connections. Sometimes these are managed by the customer, but the internet data center business and local fiber providers are going hog-wild trying to sell this. (I work for AT&T, which is selling this.)
Halon (or at least most of the Halons used for fire suppression; not sure about all of them) is non-toxic, though it'll get you a bit high, like nitrous oxide or most solvents, so being stuck in the stuff won't injure you quickly (except from flying objects that were blown around by the gas pressure.) However, it's no substitute for oxygen, and you'll probably be wanting some oxygen real soon now. If you can remember not to breathe in the stuff, try not to breathe deeply, because there's more oxygen left in your lungs than the stuff you'll be breathing in, and unfortunately, while your body can generally figure out not to breathe in water or hot smoke, it's not as good at realizing that near-room-temperature inert gases aren't very useful. Mostly, don't worry about it - find a safe door to run for and run for it, and do some deep breathing once you're outside, and try to close the door behind you.
Instead of putting all the computers in one building, put half of them in two buildings. The main cost difference is some extra real-estate preparation. And if you've got a multi-gigabit network, it's going to multiple buildings, so spread out your routers. Huge centralized computers were really useful back when mainframes were the size of dozens of refrigerators, but if you're using modern machines, they're either rack-mounted or pizza-boxes, and or else they're PC-shaped. But you've got multiples of them and can spread them around.
The statement that India is a poor country that can't afford to develop its own operating systems is laughable, especially given the timing of that speech and the Simputer deployment at the same time; the Simputer folks have done some really interesting user interface work for dealing with multiple languages and varying literacy levels.
If a Finnish grad student can afford to develop an operating system, surely somebody in India can afford to do so as well, though the government may be far too disorganized and bureaucratic to do it well. But beyond that, India's had a long tradition of training university students in Unix operating systems, and with a few hundred million educated English-speaking Indians, many of whom know Unix, the assertion that India can't afford to develop its own software when it can have it for free is an insult to one of the country's big and growing industries. (It's been about 8 years since I've worked directly with Indian software companies, but at the time they knew SunOS / Solaris just as well as I did, and Sun's done a lot of development over in India since then.)
The good news is that almost all of the horrible things you suggest won't happen. The service it purports to charge for isn't "delivering email" (that would take govt intervention) - it's "getting *you* to read a message", and if you only use cashmail.example.net for all of your email, it;s not easily circumvented.
The bad news, of course, is that nobody really wants to pay to send email to you, so you won't get any, so you'll decide that this service probably isn't for you, won't buy it, and cashmail.example.net won't make any money offering it.
Then there's the ugly news - cashmail.example.net, failing to make money from regular customers, will start spamming other mail services with You! yes, You! can get PAID to READ EMAIL and it'll just go downhill from there, really fast :-)
The computations he used weren't interesting or useful, but were very easy to verify quickly. Basically, the person doing the computation tries a large number of strings, looking for one that has an MD5 hash where the first N bits match a required value, and in some versions the input string has to have a specific form also. Checking one hash is pretty quick, but finding an input value with the right values for N bits of output takes an average of 2**N tries, so it's easy to tune the system for the amount of crunching an average machine takes to get the result.
The structure of the computation means that spammers can't cheat, because it's easily verified, and if the message doesn't include a valid piece of hashcash, you toss the message, so refusing isn't practical.
A few years back, I was out in Colorado for the August meteors. One night I was out camping and got a good view of the early ones, and the main night of the shower I was floating in a hot spring outside of Steamboat. It's an idyllic and relaxing way to watch, and beats freezing the night away.
I drove up Mt. Hamilton, east of San Jose, CA, to an area that would have been pretty dark except that the full moon was blazingly bright. There was a bit of haze, which the moon lit up as well, so only the brighter stuff showed. I'd guess that between 2am-3am we saw maybe 50-100, though we weren't counting. A few were quite impressive, but it wasn't anything like last year's amazing show. I'm not sure how much of this was because of the number of meteors going by and how much was because the moonlight made all of the dim ones invisible, while last year was dark enough we could see far more of the meteors that went by and better details on the ones we saw.
Cyclists older than first grade who ride on the sidewalk aren't safe - curb cuts, driveways, pedestrians, etc. are pretty dangerous, and cyclists are dangers to pedestrians. It's much safer for them to ride on the street, aggressively taking the middle of their lane, unless there's a bike lane available. Occasionally they'll get assaulted by cars (it's happened to me a few times), but then it cuts down on how often little old ladies stick umbrellas in their spokes.
That's an interesting idea. One of the big problems with Segway is that it costs a lot of money for something that doesn't offer a huge value. However, when you're talking about golf, a certain fraction of the market is about conspicuous consumption and doing things for fun, among people who have disposable income. So they might sell to either the golfers or to the courses, and for golfing, they really are superior to $300 electric scooters. How much does a basic golf cart cost, though?
But they will sell to spammers.
According to the SETI@HOME stats page, SETI is running about 45 TFLOPS, which is slightly ahead of the Earth Simulator's 40 TFLOPS or the LANL 10 TFLOPS machines. This isn't real precise - Top500 uses Linpack as their benchmark, which is a lot more realistic and controlled than SETI, so your mileage may vary. And of course that's Today's measurement from SETI, which is fairly variable in its CPU speed.
I also enjoyed the movie itself, but then I expected a B movie.
- They were certainly well-known when I was in college in the mid 70s, but the PL/C dialect of the PL/I checkout compiler corrected mistakes like that at run-time. (OK, it often fixed them incorrectly, but at least least it wouldn't overrun an array.) And our professors dinged us for writing programs where that happened, and made us run the programs on input decks that were maliciously designed to check for programs that overflowed their buffers.
- They were certainly well-known when K&R wrote their books on C which warned you to be careful about bounds checking when using pointers and arrays.
- They were certainly well-known in the early 80s when everybody started complaining that the gets() and scanf() routines made it easy to overrun buffers on input when you weren't doing it by hand.
- They were certainly well-known in the late 80s when the Morris Worm wandered around a lot of the machines in the internet.
- They were certainly well known when the C++ string-handling libraries were designed to NOT overrun buffers, and when Java was designed to not even have pointers, and had array objects that checked bounds for you.
- There are enough software engineering CASE tools that try to find problems more complex than lint() looks for, though perhaps array bounds checking isn't something they check effectively.
I like C - I really like it. It's time to stop using it. It's time to stop shipping code that has array bounds problems, and security code that hasn't been proofread for them. And it's time to stop using programs that run as root when they don't need to. This isn't the 80s any more.There are other bugs out there - a popular attack is to try to abuse dotdots in path names, which there's more excuse for forgetting to check, and there are things like race conditions that are genuinely hard to check for (e.g. what happens when somebody's ripping up your temp files while your program is running), though checking return codes on system calls and doing something appropriate about failures is a good start.
However, if your computer is a laptop that you run on batteries for a significant fraction of the time, be careful - NiMH batteries really don't like to power CPU-burners, and as they age, they tend to fail in ugly ways. I used to have a one-hour train commute, and my laptop simply did *not* like running GIMPS. Also, even if I turned it off when I was running on batteries, it slowed down the recharge process significantly when I plugged back in again, and I don't think it liked that either.
Seals make breathing holes in the ice. Both for the people and the bears, the standard method of hunting seals is to hang out near the breathing holes and grab the seals when they come up for air. As ice melt increases the open water, the seals have much more open space to breathe in, and hunting them becomes impossible. They're a major food source for the bears, and also for any people doing native subsistence hunting. Fishing is more possible if there's open water, but difficult. The people also do some bear hunting for food, and as the number of seals decreases, the people will probably do more bear hunting, greatly increasing pressure on the bears.
It might be possible to build a device like this that's more cost-effective than system RAM, though this one isn't priced that way. You're trading the cost of a board for the ability to use cheapo PC100 or PC133 memory instead of PC2100DDR or whatever the latest and most expensive stuff is, and if you're careful, you can design it so it's not subject to the same memory limitations that the motherboard is, though that may be difficult with a 32-bit PCI bus. It'd be faster if it ran off the AGP bus instead of PCI, but that limits the applications to servers with slow or no video adapters, while PCI is probably good enough for most users who may want this to accelerate their graphics applications as well.
This gives you your bits right now, and they were just marvellous as journalling accelerators for databases or NFS filesystems.
Dude - it's not there just to give your machine more RAM, it's there to be much much faster than your disk drive. The speedup isn't because it can push data a bit faster than SCSI can - it's because real disk drives have ~8ms seek times and ~8ms rotational delays, so the number of separate items of data you can write to your disk are limited by how fast the disk spins around and the heads slide back and forth, not by how fast it can pump data once it's in the right place. It *would* be nice if the motherboard could handle more memory, but for this application, large quantities of cheap memory are just fine, and you can save your northbridge and AGP port for stuff that needs to be fast.