The trouble is making sure the server is still running after your death. Personal boxen will likely be turned off. Scheduling such a process on a work server might be frowned upon. Asking a friend to host it for you doesn't cover all the bases. (what if they die at the same time?)
Then you've got the problem of clock glitches. What if the server boots up, thinks it's 2005, notices the elapsed time, and sends your emails before getting an NTP update?
What's needed is a distributed method of tracking keepalive messages (ha! I kill me!) and then taking action if they stop coming. The system should run on several machines, and they should vote together, to ensure that one misconfiguration doesn't screw up the works. Another trick is keeping the last-message private until it's sent.
When it's all taken into consideration, it's usually easier to let humans make the determination of your death. But don't leave it up to ONE human. Suppose someone found your envelope with the mylastemail document in it, and mailed it in as a prank?
Cryptographers have protocols for dealing with this, it turns out. Assume you have 10 trusted friends, and you want to set it up so that any 6 of them can decrypt your message. Consider "forward error correction" protocols, which allow data to be reconstructed even if some blocks are missing. Simply encrypt your message and then FEC-encode it into 10 blocks, so that a minimum of 6 blocks are required to make the original.
Give each block to one of your friends, with strict instructions not to let any of the others see it until after your death. Ask them to make really sure you're gone before revealing their parts of the key. The last thing you need is for a somewhat exaggerated report of your death to trigger the doomsday emails!
Funny enough, I came up with this exact idea a few years back, before Columbine and everything made it politically incorrect.
In addition to automatically building Quake maps for the building of your choice, it would help make up for my terrible sense of direction indoors. I get turned around in houses the first time I visit. Larger structures like hospitals and schools are downright labyrynthine. Having a map that builds itself during my travels (a la the self-revealing map in an RPG) would be a boon.
My version would've been a head-mounted stereoscopic camera unit, with software that recognized edges and angles. By watching my motion through the space and computing perspective changes, it could calculate distances and dimensions. Recording samples of textures would be fairly simple.
The system would quickly learn which objects are part of the scenery and which are mobile, by noticing changes in the environment when you visit the same area multiple times.
If miniaturized to the glasses-frame level, it could become always-wearable and answer questions like "where did I put my mug?" and "is the upstairs window still open?" by simply knowing the names of objects and locations.
Apparently the use of laser scanners in the current version indicates that plain-sight image recognition still isn't up to where it should be. Hmmph.
Why, you'd go to TurboMinivan.com of course! "Screw motoring. Let's race!"
Trust me on this one, you just have to check out the page. It's almost scary what a junkyard van and a few bucks in mods can get you. The ultimate sleeper! To quote the site: "He who judges a book by its cover will soon be staring at taillights."
I've said this for years, and it's formed the central analogy of my explanation of what makes hackers hack. Almost everyone can understand the drive to explore, tweak, and compete when it's placed into the context of car enthusiasm. To me it's an identical mindset with different tools. Sympathy for hackers seems to skyrocket when people can connect the hobby to something familiar.
I'm an irregular poster on MatrixOwners.com and GenVibe.com, which are nearly identical and I'm not sure why both exist when they serve the exact same need. (the sites AND the cars!). It's funny how much difference there is between the content of the forums though. Drivers of the Pontiac version seem more concerned with function than form, whereas the Toyota-centered site gets more postings about cosmetic modifications. (Personally, I drive a Matrix but I could care less about decals and painted calipers. I want more outlets!)
During the wee hours of the morning, I started YDJK up to hear the normal intro replaced with "aaaand welcome! to the insominiac edition of you don't know jack!"
I'm pretty sure it had knowledge of other holidays too, I think it had a few special questions for columbus day and stuff. Have to dig out the CDs and find out.
I've only played briefly with some old Itronix products, but I'm sure they're on par with the Toughbook, my personal favorite machine. The trouble is, when you tell someone that a machine is rugged, they tend to try to prove it. Either way, someone's going to have to pay for repairs when the kids manage to damage them.
I throw mine around all the time just to show it off. Mind you, it's survived with nothing more than scratches, but kids are creative. After kicking the Toughbook down a flight of stairs, the gel-mounted hard drive did begin to develop bad sectors... "I swear! The cement mixer ate my homework!"
You can get rugged laptops for very good prices on the used market, but buying them new, they usually go for about double the price of a regular machine. Nobody makes entry-level rugged machines. I'm a Michigan taxpayer and I think this whole program is a colossal waste of money. It would only be worse if the machines were more expensive.
Why is it a waste? Because they've given almost no thought to actually teaching the kids or the teachers how to effectively use these machines in education. The thinking is similar to television parenting in the 1980s: Park one of these gizmos in front of a kid and walk away.
The fact that these things are going to have wireless capability just opens up another dumptruck of worms. The creative programmers will figure out fun things to do with a massive computing cloud, while the schools run ragged trying to prevent it.
And therein lies the crux of the problem: The educational value of a computer is TINKERING WITH IT. You have to be able to take it apart, change things, experiment with the software, and learn by doing. That's the reason every one of us Slashdotters is here today. By giving someone a computer and saying "but don't play with it! You might damage the school's property", you sabotage its strongest learning potential.
I fear the the golden age of computing is waning. ROM-based computers like the Commodore 64 were perfect for experimenting. It was practically impossible for curiousity to damage the machine. Now with OS's stored on a hard drive, computers manage to screw themselves up without any help at all! Forcing a child to tote this fantastic toy around, but requiring them to NOT play with it, is a disaster.
Making a more conservative "stable" code branch isn't going to improve anything if the underlying network (by which I mean the vast body of nodes and datastores) doesn't work. The difference between a Yugo and a Porsche is irrelevant when the roads are flooded.
What Freenet needs, and what fredisdead hopes to accomplish, is a network on which routing actually routes, and datastores actually store data. It would be icing on the cake of address resolution keys actually resolved addresses, too. The trouble with the development network is that it's too big, and too unwieldy, to do anything efficiently with the current routing algorithms. Freenet has serious issues with scalability, and the fact that most users don't want to run the daily-upgrade treadmill doesn't seem to be helping.
We can move a lot of traffic, and most of the whiny users, onto a separate "production" network. If the effort takes off, it'll be big enough to provide useful anonymity but small enough that routing might still be functional. Then development can continue, hopefully with a more enthusiastic user base, which can upgrade every time Toad sneezes and help debug Next-Generation Routing, which I'm still optimistic about.
You're absolutely right that Freenet has always been straightforward about its status as a work in progress. "Stable" is, in the sense that it doesn't spontaneously stop accepting connections, or decide to use 100% CPU for no apparent reason. But "stable" and "useful" are two vastly different things. The users that Freenet has attracted want something useful. If the development network begins to outperform the production network, then perhaps another switch will be in order. But there's no sense in trying to force users to remain on a useless network when they obviously have things to get done and are willing to split off in order to accomplish them.
In the grand scheme of things, I agree that fredisdead is a minor event that's probably not deserving of a Slashdot story. But it's a social statement: Freenet is too interesting, and too widely publicized, to remain so broken for so long. Develop, test, and develop some more. But don't drag everyone along for the bumpy ride.
A year or two ago, a friend of mine from work bought his first computer, something to accompany his DV camera. It had a firewire card in it, but neither the computer nor the camera had included a firewire cable. Back to the store we went.
Best buy wanted $50 for a 4-foot cable. That struck me as obscenely high, so I drove around for a bit, and eventually found one at Radio Shack for $15, which I deemed acceptable for a retail outlet.
Just the previous month, another friend of mine had purchased a firewire card online (some pricewatch vendor) for $14 and it came with two cables... *sigh*
Seagate has some amazingly quiet drives based on fluid bearings, I'm assuming that this fairly obvious choice has already occured to you and was deemed unsuitable for some reason.
Barring a regular hard drive, the first and most obvious method is a solid-state disk that's designed for continuous use. They're not cheap, but they're totally silent and quite fast, too.
As was already suggested, a RAM disk that periodically backs itself up to CF would work too. RAM is cheap! If you don't need all that CPU power, consider underclocking your setup to reduce the memory's heat generation, and therefore your fan's duty cycle.
You could try a magneto-optical disk. Some of the old 230MB 3.5" MO drives are nearly silent, and the media's rated for millions of writes and decades in storage. I don't know how noisy the 5.25" versions are, but they should be pretty quiet too, mostly owing to low spin speeds and finely machined parts. Again they'd be better as backing stores for a large RAM disk, due to limited i/o speeds and seek times. Being removable, backups are a piece of cake too.
Laptop hard drives are also pretty quiet, because their spindle RPMs are lower than desktop drives (5400 as opposed to 7200 or 10,000). Their platters are also smaller, meaning that the airspeed of the edge of the platter is much lower, creating less turbulence. Being physically smaller also means that you can mount it in rubber vibration isolators, preventing the computer's case from acting as a sounding board for spindle noise and seek clatter.
Also, check hard drive makers' websites for quiet seek modes. The drive's firmware can choose to drive the head servo in a noisy "performance" mode, or to smooth out the edges of the seek motions in a "quiet" mode. It results in a modest performance drop but a distinct reduction in noise.
Next step: Throw the entire computer into an acoustic printer enclosure. Back when impact dot matrix printers were the norm (and they still are in businesses that use multipart forms), everyone hated the racket they made. Elaborate printer cages were built, lined with acoustic foam and equipped with quiet fans to keep the occupant cool. This will drop a few decibels off any obnoxious machine, and they're designed to be easily opened for paper feeding, ribbon changing, etc. The only downside is bulk.
You can also throw bits of acoustoabsorbent foam into the computer's case wherever you find room. I live a few miles from a foam supplier so I picked up a few scraps. Rubber cement or spray-on adhesive work well. Any car stereo shop can sell you little bits of Dynamat, with a self-adhesive backing. An ITX case won't afford much space, but every little bit helps to cut down on panel vibrations and reflected noise.
When something claims to be rugged, you never take its word for it do you? It's in that spirit that I present you with high-res photos of Toughbooks being shot at during this summer's Independence Day celebrations.
If you have a friend with a few acres of land, and a friend with a bunch of guns, and a pile of "ruggedized" hardware, I highly recommend trying this at home. Mouse kicking and keyboard throwing simply can't compare to putting slugs through magnesium laptops. We also ran over a Toughbook, and detonated a Nextel i1000 and a watermelon. Squibs are your friends, even more so when they're at the end of long pieces of wire. Eye and ear protection are cheap compared to the thrill of taking aim at a f00f-bugged Pentium.
This year's results were about as I expected: Shotgun blasts and small handguns bounce off and leave small dents, unless at point-blank range. Medium-sized handguns penetrate one or two layers, but based on the laptop's construction, it's likely that had a hard drive been mounted in the cavity, it would've been untouched. Large handguns and rifles go straight through, some of them fast enough to ignite the magnesium dust they generate, making a nice flash as they exit. (None of the weapons actually lit the thing on fire. We'll have to try a flare gun next year.)
Next year's July-4th festivities should be even more fun. The plan is to amass the widest possible variety of cheap "rugged" hardware, and set it all up running. Then shoot 'em all with progressively larger calibers until each stops responding to pings.
There were a few EPYX games that were self-booting on 720k floppies. Provided you had 512k of physical RAM and a CGA card, you were all set.
Made it tricky to break the copy-protection too, because the disk had bad sectors strategically placed, and it was a pain to disassemble the thing because it ran its own OS and everything.
Your project sounds very similar in needs to another application I'd discussed with a friend some time ago. When the Civil Air Patrol gets called out on a search-and-rescue mission, they frequently fly over the suspected area with a video camera, sending frames down to the ground with slow-scan TV so that an expert on the ground can identify likely spots to search. The image quality sucks and the data rate is worse.
It'd be nice if these folks could carry a multi-megapixel digicam on the plane, snap pics of anything interesting, and have the images sent to the ground for viewing/zooming on a laptop. The only trouble is, the search area is usually several miles on a side, well over the range of normal 802.11a/b. The solution we came up with involves a cadet on the ground with a high-gain dish antenna being told "keep this pointed at that plane". Cheaper and more reliable than an automatic antenna tracker, for sure.:)
So what we need here is a way to interface with the digital camera. As soon as a photo is taken, we should suck it of the camera's memory and buffer it for transmission to the ground station as soon as possible. Point to ponder: Assume that wireless connectivity is intermittent. Do you transmit the most recent pictures first, or the oldest pictures first, to make sure the base station has the most useful data possible? (LIFO or FIFO?)
Some time ago, I proposed a bluetooth CF module which would appear as a large FAT filesystem. It would have a limited amount of "cache" memory, where images would immediately be written, and then it would then link to a large hard drive sitting in the user's pocket and free the cache for more images. An 802.11b version would suck more battery than bluetooth, but allow longer range operation. The trick isto emulate a filesystem, so firmware hacks aren't needed. (If you could mess with the camera's firmware, you could use an existing CF wireless card and let the camera handle the protocol, right?) Nikon seems to have released a similar product but it's vaporware and only works with one particular camera.
In lieu of sitting straight in the camera's media slot, there's always software that controls the camera via serial or USB. The problem is, most of it seems designed for interactive use. I don't know whether the protocols support lurking in the background to just suck files off the flash card, without interfering with the camera's normal operation. Several of the packages are based on a common code base with a protocol that's fairly well documented, so rolling your own isn't out of the question. Let's assume for the sake of discussion that your camera supports this and suitable software can be found or written.
If you can get by on RS232's peak speed of 115200bps, and if the software can be worked out, there are several hardware options. Several other posters have suggested PDAs with wireless cards. That's a great idea, especially if you can strip off the screen and case to save weight. Some suggested the Soekris net4511 or similar. It's got a low-power 486 chip, serial ports, ethernet ports, and a PCMCIA slot for your wireless card. Or, you could hack up an existing 802.11b accesspoint to run linux and use its console port to connect to the camera. (Note: The Eumitcom-based APs are getting hard to find now. Not a platform with future potential.) There's a similar project for the Apple Airport base station, but it's limited to etherbooting, probably not suitable for this application.
You could use a pair of Ricochet modems dialed to each other (auto-answer on the chopper, and dial from the ground), in which case they simp
Why not just move the research to Freenet? It has the tools for information sharing in a completely free environment. The Frost messageboard software, which runs on top of Freenet, already has an xbox board with some activity in it.
Eddie was pissed when I dropped my Toughbook down his stairs. Luckily, further examination revealed that the stairs had only taken 3 small dents, none of which were obvious to the casual observer.
The toughbook, of course, failed to notice.
Why would you carry around a computer that's so delicate you can't even nudge it off a table 40 or 50 times? It's just silly when your $1700 computer is less durable than a $30 dead-tree book. Don't put up with wimpy hardware.
Canon has used ultrasonic piezoelectric motors in their lenses for years. These are the "mexican wave" (wtf?) motors that the New Scientist article mentions. I'm not sure why they'd be any more expensive than the origami motors described here.
Piezoelectric stick-slip actuators are nothing new. Those units built at Cambridge apparently pre-date the units mentioned in the article, but the surface preparation technique is somewhat different.
Get a little "ON AIR" light for your cube.
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I've seen these little "on the phone!" lights sold in the same catalogs that sell handset kits for desk phones and stuff like that. You could easily use white stencils or white-on-clear labels to make one into a nice little "on air" light for yourself.
Of course, be sure to turn it off once in a while. You don't want to be the boy who cried "do not disturb".
Not even in the lunchroom! Jeebus, that stuff reeks. There should be a special microwave, outside under an awning where the smokers sit, specifically for popcorn. It should be popped, shaken, opened, aired-out, and half eaten before bringing it indoors.
Waving your smelly popcorn in my airspace is an invitation for me to overindulge on burritos tonight, and tomrrow spend a lot of time inspecting the bulletin board right next to your cubicle.
Ditto on the perfume thing, people don't realize how intensely that stuff smells. I used to know when one particular secretary was in the office because I'd start sneezing in the hallway.
Re:Thermostats: They are *NOT* your friend
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HVAC contractors frequently install fake thermostats so people can enjoy the placebo effect of twisting a knob, without actually changing the temperature. The real t-stat is in the hallway near the boss's office, of course.
Re:Thermostats: They are *NOT* your friend
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GotchaNOW! is automatic motion-monitoring webcam software. They've got several testimonials from when gotchanow recorded someone stealing office supplies, etc... Unfortunately, it's payware.
You're right that optical media, or anything that rotates only when being accessed, is very secure in the event that the machine takes a hit while the media is in the drive. For this reason, you might want to keep the CD-RW drives in the machines even if you're using a different technique for nightly backup, and do weekly backups to an RW disc or something.
A USB flash device, left plugged in to the machine for days at a time, would be connected to the PC's power supply during such a strike and might sustain damage. However, there are USB surge protectors made by several companies, they're just not super cheap. (Personally, I'd throw a $2 16V MOV across VCC and GND, and call it a day.)
Look at the costs before selecting a keychain drive. You might be able to get a USB-CF reader, and a large CF card, cheaper than a straight USB keychain drive.
Why exactly are you worried about lightning anyway? I'm sure you've got a surge protector on the AC power input.. are these machines connected to a lot of weird interfaces that would be impractical to put protection on? I'm imagining a warehouse environment where RS232 links and stuff might make things difficult, but B&B makes surge protectors for just about every interface you can imagine. APC has a pretty wide selection of surge protectors too.
If the threat model didn't include "massive jolt frying everything in the box", you could get away with some much cheaper backup solutions. Get a batch of surplus or refurb hard drives. They're cheap in single quantities, and practically free if you buy by the crate! Set your software to spin the drive down except during the nightly backup run. This reduces the chances of all sorts of failures, including data corruption risks caused by power glitches during operation.
I don't know if it would be of any use to your application, but having a ten-gig backup device means you could keep old backups for quite a while before reusing the space.
The hot-swap features are dubious. They technically won't hurt the drive, but your OS will be royally pissed at you if you yank a drive right off an IDE chain. Particularly if it was jumpered as Master.
There's a simple solution, though: USB/Firewire external drives have support in the drivers for hot connection and disconnection. Usually you have to click an icon to tell the drivers to prepare, but after a moment you'll be permitted to remove such a device. "But!", you say, "that's an extra power supply and an extra case sitting around!"
"Not so fast", I reply. You can combine the drive-bay-mounted removable racks that we all know and love, with the hot insertion and removal of USB or Firewire! Check out this one which I particularly like because of the easy availability of extra trays.
That model is USB2.0 capable, but of course all such devices are USB1.1 backwards compatible, so if your motherboard has a 1.1 controller and you're only backing up a bit of data, there's no need to buy a 2.0 controller.
I've used "PC Inspector File Recovery" with great success in recovering files from a smartmedia card that I accidentally deleted from the camera's interface. Compactflash should be similar.
CF cards shouldn't get wet! They have plenty of space inside for moisture to linger. You got lucky. If I got a CF card wet and it didn't work after blowing the holes dry, I'd crack it open and rinse the innards with alcohol, then try again. I've got pics of the insides of a CF card on my photo gallery under the Tech album.
For those who want to attach CF cards directly to IDE controllers, adaptersareavailable.
For the first few minutes things were fine, my ISP was still up when I decided to shut down early, rather than running the UPS battery down hard. Cell phones were fine too, for a couple hours.
Later Thursday night I tried to get back online from my laptop, and my local ISP (who uses Megapop for dialin ports) would answer and connect, I'd get an IP address, but my packets went nowhere. Tracert stopped at hop 1.
So, knowing that the phone system was up, I simply dialed out of the affected area. Calling a POP in another city worked fine, and I was able to touch base with a few friends online before the laptop battery gave out.
Friday morning, having recharged the laptop in the car, I gave it another go. This time, the far-away ISP connected but wouldn't route packets. I decided it wasn't very important, that the fridge wouldn't stay cold much longer, and I gave up on the internet in favor of starting the generator.
Megapop: B for staying up as long as they did, F for eventually failing. Big batteries followed by dead generator? Final grade, low D.
When I signed up with Nextel as a cell phone carrier, I did so with the knowledge that their history had been as a mobile radio provider to law enforcement and public safety agencies. I figured if anyone's network would be well engineered, it would be theirs. Oops.
For the first few hours, my phone said it could see the tower, but circuits were predictably busy. That's understandable. Then some time Thursday evening the tower went off the air, and didn't come back until Friday afternoon, for 2 hours, then it disappeared again. I took to checking my voicemail from a POTS line. During the next day I got and lost signal several times, including one weird moment when the phone's light blinked red (It's only supposed to know solid red or blinking green) and the display said "Ready", instead of "NEXTEL".
Starting Thursday afternoon, my (quite expensive) Packetstream service was useless. Even when I could make voice calls, the internet was unreachable. This has me really baffled. The cell site was up, but something at the back-end was down? If anything, I'd expect their switching facilities to be better protected than the individual sites! I'm cancelling Packetstream in favor of the much cheaper and probably equally unreliable data service from T-Mobile.
Nextel: C- for unreliable service starting immediately, F for getting even worse after that. Shame on you.
POTS remained working perfectly the whole time, despite the fact that I know my line to be carried through a SLIC-hut. Those batteries did exceptionally well. Except for the first busy hour following the blackout when everybody called around to check up on family, I never had problems making calls. After replacing all the cordless phones in the house with corded models, life returned to a sweaty version of normal. Curiously enough, one of our three POTS lines failed midway through the outage, and didn't come back until late Sunday. Coincidental failure?
SBC: A for having dialtone the whole time, B+ for only giving "all circuits busy" messages a few times under what must have been heavy load.
I'd bet otherwise. The local telco's CO has 18+ hours of battery and a week of diesel/kerosene, and they test-run their turbine every 6 months to make sure it can carry the load. CO's just don't go down, the uptime of switches is measured in decades, and most offices have never had a power hit on the equipment side.
It's possible that your line doesn't come straight from the CO, rather it hops through a remote equipment location (a "hut" or "vault"), which has batteries but no generator.
Huts, vaults, and cellular base stations aren't considered big enough to deserve their own generators, but they have big sockets outside, where a trailer-mounted generator can be plugged in. Unfortunately, nobody plans for all however-many-thousand sites to be off the grid at the same time, and there are usually only 2 or 3 techs with trucks towing generators around for any given region.
It's also possible that your circuits aren't carried on copper at all. If you have more than 4 T-1's, it's more economical to bring them in on a fiber loop than maintaining a bunch of T-1 spans. An OC-3 ring can carry 3 DS3 (T-3) circuits, or 84 DS1 (T-1) circuits. Therefore, such a ring will usually leave the CO and wander through town, with "nodes" in many different customers' buildings before returning to the CO. Each node on customer premises lives in a big blue cabinet, with batteries at the bottom which will sustain it for a few hours. SONET ring architecture is such that a single failure doesn't kill traffic, but if nodes on either side of you fail, you're isolated.
Without knowing more about your situation, this is all I can say, but I'm very certain that the C.O. never lost battery.
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The trouble is making sure the server is still running after your death. Personal boxen will likely be turned off. Scheduling such a process on a work server might be frowned upon. Asking a friend to host it for you doesn't cover all the bases. (what if they die at the same time?)
Then you've got the problem of clock glitches. What if the server boots up, thinks it's 2005, notices the elapsed time, and sends your emails before getting an NTP update?
What's needed is a distributed method of tracking keepalive messages (ha! I kill me!) and then taking action if they stop coming. The system should run on several machines, and they should vote together, to ensure that one misconfiguration doesn't screw up the works. Another trick is keeping the last-message private until it's sent.
When it's all taken into consideration, it's usually easier to let humans make the determination of your death. But don't leave it up to ONE human. Suppose someone found your envelope with the mylastemail document in it, and mailed it in as a prank?
Cryptographers have protocols for dealing with this, it turns out. Assume you have 10 trusted friends, and you want to set it up so that any 6 of them can decrypt your message. Consider "forward error correction" protocols, which allow data to be reconstructed even if some blocks are missing. Simply encrypt your message and then FEC-encode it into 10 blocks, so that a minimum of 6 blocks are required to make the original.
Give each block to one of your friends, with strict instructions not to let any of the others see it until after your death. Ask them to make really sure you're gone before revealing their parts of the key. The last thing you need is for a somewhat exaggerated report of your death to trigger the doomsday emails!
Funny enough, I came up with this exact idea a few years back, before Columbine and everything made it politically incorrect.
In addition to automatically building Quake maps for the building of your choice, it would help make up for my terrible sense of direction indoors. I get turned around in houses the first time I visit. Larger structures like hospitals and schools are downright labyrynthine. Having a map that builds itself during my travels (a la the self-revealing map in an RPG) would be a boon.
My version would've been a head-mounted stereoscopic camera unit, with software that recognized edges and angles. By watching my motion through the space and computing perspective changes, it could calculate distances and dimensions. Recording samples of textures would be fairly simple.
The system would quickly learn which objects are part of the scenery and which are mobile, by noticing changes in the environment when you visit the same area multiple times.
If miniaturized to the glasses-frame level, it could become always-wearable and answer questions like "where did I put my mug?" and "is the upstairs window still open?" by simply knowing the names of objects and locations.
Apparently the use of laser scanners in the current version indicates that plain-sight image recognition still isn't up to where it should be. Hmmph.
Why, you'd go to TurboMinivan.com of course! "Screw motoring. Let's race!"
Trust me on this one, you just have to check out the page. It's almost scary what a junkyard van and a few bucks in mods can get you. The ultimate sleeper! To quote the site: "He who judges a book by its cover will soon be staring at taillights."
I've said this for years, and it's formed the central analogy of my explanation of what makes hackers hack. Almost everyone can understand the drive to explore, tweak, and compete when it's placed into the context of car enthusiasm. To me it's an identical mindset with different tools. Sympathy for hackers seems to skyrocket when people can connect the hobby to something familiar.
I'm an irregular poster on MatrixOwners.com and GenVibe.com, which are nearly identical and I'm not sure why both exist when they serve the exact same need. (the sites AND the cars!). It's funny how much difference there is between the content of the forums though. Drivers of the Pontiac version seem more concerned with function than form, whereas the Toyota-centered site gets more postings about cosmetic modifications. (Personally, I drive a Matrix but I could care less about decals and painted calipers. I want more outlets!)
During the wee hours of the morning, I started YDJK up to hear the normal intro replaced with "aaaand welcome! to the insominiac edition of you don't know jack!"
I'm pretty sure it had knowledge of other holidays too, I think it had a few special questions for columbus day and stuff. Have to dig out the CDs and find out.
I've only played briefly with some old Itronix products, but I'm sure they're on par with the Toughbook, my personal favorite machine. The trouble is, when you tell someone that a machine is rugged, they tend to try to prove it. Either way, someone's going to have to pay for repairs when the kids manage to damage them.
I throw mine around all the time just to show it off. Mind you, it's survived with nothing more than scratches, but kids are creative. After kicking the Toughbook down a flight of stairs, the gel-mounted hard drive did begin to develop bad sectors... "I swear! The cement mixer ate my homework!"
You can get rugged laptops for very good prices on the used market, but buying them new, they usually go for about double the price of a regular machine. Nobody makes entry-level rugged machines. I'm a Michigan taxpayer and I think this whole program is a colossal waste of money. It would only be worse if the machines were more expensive.
Why is it a waste? Because they've given almost no thought to actually teaching the kids or the teachers how to effectively use these machines in education. The thinking is similar to television parenting in the 1980s: Park one of these gizmos in front of a kid and walk away.
The fact that these things are going to have wireless capability just opens up another dumptruck of worms. The creative programmers will figure out fun things to do with a massive computing cloud, while the schools run ragged trying to prevent it.
And therein lies the crux of the problem: The educational value of a computer is TINKERING WITH IT. You have to be able to take it apart, change things, experiment with the software, and learn by doing. That's the reason every one of us Slashdotters is here today. By giving someone a computer and saying "but don't play with it! You might damage the school's property", you sabotage its strongest learning potential.
I fear the the golden age of computing is waning. ROM-based computers like the Commodore 64 were perfect for experimenting. It was practically impossible for curiousity to damage the machine. Now with OS's stored on a hard drive, computers manage to screw themselves up without any help at all! Forcing a child to tote this fantastic toy around, but requiring them to NOT play with it, is a disaster.
Making a more conservative "stable" code branch isn't going to improve anything if the underlying network (by which I mean the vast body of nodes and datastores) doesn't work. The difference between a Yugo and a Porsche is irrelevant when the roads are flooded.
What Freenet needs, and what fredisdead hopes to accomplish, is a network on which routing actually routes, and datastores actually store data. It would be icing on the cake of address resolution keys actually resolved addresses, too. The trouble with the development network is that it's too big, and too unwieldy, to do anything efficiently with the current routing algorithms. Freenet has serious issues with scalability, and the fact that most users don't want to run the daily-upgrade treadmill doesn't seem to be helping.
We can move a lot of traffic, and most of the whiny users, onto a separate "production" network. If the effort takes off, it'll be big enough to provide useful anonymity but small enough that routing might still be functional. Then development can continue, hopefully with a more enthusiastic user base, which can upgrade every time Toad sneezes and help debug Next-Generation Routing, which I'm still optimistic about.
You're absolutely right that Freenet has always been straightforward about its status as a work in progress. "Stable" is, in the sense that it doesn't spontaneously stop accepting connections, or decide to use 100% CPU for no apparent reason. But "stable" and "useful" are two vastly different things. The users that Freenet has attracted want something useful. If the development network begins to outperform the production network, then perhaps another switch will be in order. But there's no sense in trying to force users to remain on a useless network when they obviously have things to get done and are willing to split off in order to accomplish them.
In the grand scheme of things, I agree that fredisdead is a minor event that's probably not deserving of a Slashdot story. But it's a social statement: Freenet is too interesting, and too widely publicized, to remain so broken for so long. Develop, test, and develop some more. But don't drag everyone along for the bumpy ride.
A year or two ago, a friend of mine from work bought his first computer, something to accompany his DV camera. It had a firewire card in it, but neither the computer nor the camera had included a firewire cable. Back to the store we went.
Best buy wanted $50 for a 4-foot cable. That struck me as obscenely high, so I drove around for a bit, and eventually found one at Radio Shack for $15, which I deemed acceptable for a retail outlet.
Just the previous month, another friend of mine had purchased a firewire card online (some pricewatch vendor) for $14 and it came with two cables... *sigh*
Seagate has some amazingly quiet drives based on fluid bearings, I'm assuming that this fairly obvious choice has already occured to you and was deemed unsuitable for some reason.
Barring a regular hard drive, the first and most obvious method is a solid-state disk that's designed for continuous use. They're not cheap, but they're totally silent and quite fast, too.
As was already suggested, a RAM disk that periodically backs itself up to CF would work too. RAM is cheap! If you don't need all that CPU power, consider underclocking your setup to reduce the memory's heat generation, and therefore your fan's duty cycle.
You could try a magneto-optical disk. Some of the old 230MB 3.5" MO drives are nearly silent, and the media's rated for millions of writes and decades in storage. I don't know how noisy the 5.25" versions are, but they should be pretty quiet too, mostly owing to low spin speeds and finely machined parts. Again they'd be better as backing stores for a large RAM disk, due to limited i/o speeds and seek times. Being removable, backups are a piece of cake too.
Laptop hard drives are also pretty quiet, because their spindle RPMs are lower than desktop drives (5400 as opposed to 7200 or 10,000). Their platters are also smaller, meaning that the airspeed of the edge of the platter is much lower, creating less turbulence. Being physically smaller also means that you can mount it in rubber vibration isolators, preventing the computer's case from acting as a sounding board for spindle noise and seek clatter.
Also, check hard drive makers' websites for quiet seek modes. The drive's firmware can choose to drive the head servo in a noisy "performance" mode, or to smooth out the edges of the seek motions in a "quiet" mode. It results in a modest performance drop but a distinct reduction in noise.
Next step: Throw the entire computer into an acoustic printer enclosure. Back when impact dot matrix printers were the norm (and they still are in businesses that use multipart forms), everyone hated the racket they made. Elaborate printer cages were built, lined with acoustic foam and equipped with quiet fans to keep the occupant cool. This will drop a few decibels off any obnoxious machine, and they're designed to be easily opened for paper feeding, ribbon changing, etc. The only downside is bulk.
You can also throw bits of acoustoabsorbent foam into the computer's case wherever you find room. I live a few miles from a foam supplier so I picked up a few scraps. Rubber cement or spray-on adhesive work well. Any car stereo shop can sell you little bits of Dynamat, with a self-adhesive backing. An ITX case won't afford much space, but every little bit helps to cut down on panel vibrations and reflected noise.
Good luck!
When something claims to be rugged, you never take its word for it do you? It's in that spirit that I present you with high-res photos of Toughbooks being shot at during this summer's Independence Day celebrations.
If you have a friend with a few acres of land, and a friend with a bunch of guns, and a pile of "ruggedized" hardware, I highly recommend trying this at home. Mouse kicking and keyboard throwing simply can't compare to putting slugs through magnesium laptops. We also ran over a Toughbook, and detonated a Nextel i1000 and a watermelon. Squibs are your friends, even more so when they're at the end of long pieces of wire. Eye and ear protection are cheap compared to the thrill of taking aim at a f00f-bugged Pentium.
This year's results were about as I expected: Shotgun blasts and small handguns bounce off and leave small dents, unless at point-blank range. Medium-sized handguns penetrate one or two layers, but based on the laptop's construction, it's likely that had a hard drive been mounted in the cavity, it would've been untouched. Large handguns and rifles go straight through, some of them fast enough to ignite the magnesium dust they generate, making a nice flash as they exit. (None of the weapons actually lit the thing on fire. We'll have to try a flare gun next year.)
Next year's July-4th festivities should be even more fun. The plan is to amass the widest possible variety of cheap "rugged" hardware, and set it all up running. Then shoot 'em all with progressively larger calibers until each stops responding to pings.
There were a few EPYX games that were self-booting on 720k floppies. Provided you had 512k of physical RAM and a CGA card, you were all set.
Made it tricky to break the copy-protection too, because the disk had bad sectors strategically placed, and it was a pain to disassemble the thing because it ran its own OS and everything.
Your project sounds very similar in needs to another application I'd discussed with a friend some time ago. When the Civil Air Patrol gets called out on a search-and-rescue mission, they frequently fly over the suspected area with a video camera, sending frames down to the ground with slow-scan TV so that an expert on the ground can identify likely spots to search. The image quality sucks and the data rate is worse.
:)
It'd be nice if these folks could carry a multi-megapixel digicam on the plane, snap pics of anything interesting, and have the images sent to the ground for viewing/zooming on a laptop. The only trouble is, the search area is usually several miles on a side, well over the range of normal 802.11a/b. The solution we came up with involves a cadet on the ground with a high-gain dish antenna being told "keep this pointed at that plane". Cheaper and more reliable than an automatic antenna tracker, for sure.
So what we need here is a way to interface with the digital camera. As soon as a photo is taken, we should suck it of the camera's memory and buffer it for transmission to the ground station as soon as possible. Point to ponder: Assume that wireless connectivity is intermittent. Do you transmit the most recent pictures first, or the oldest pictures first, to make sure the base station has the most useful data possible? (LIFO or FIFO?)
Some time ago, I proposed a bluetooth CF module which would appear as a large FAT filesystem. It would have a limited amount of "cache" memory, where images would immediately be written, and then it would then link to a large hard drive sitting in the user's pocket and free the cache for more images. An 802.11b version would suck more battery than bluetooth, but allow longer range operation. The trick isto emulate a filesystem, so firmware hacks aren't needed. (If you could mess with the camera's firmware, you could use an existing CF wireless card and let the camera handle the protocol, right?) Nikon seems to have released a similar product but it's vaporware and only works with one particular camera.
In lieu of sitting straight in the camera's media slot, there's always software that controls the camera via serial or USB. The problem is, most of it seems designed for interactive use. I don't know whether the protocols support lurking in the background to just suck files off the flash card, without interfering with the camera's normal operation. Several of the packages are based on a common code base with a protocol that's fairly well documented, so rolling your own isn't out of the question. Let's assume for the sake of discussion that your camera supports this and suitable software can be found or written.
If you can get by on RS232's peak speed of 115200bps, and if the software can be worked out, there are several hardware options. Several other posters have suggested PDAs with wireless cards. That's a great idea, especially if you can strip off the screen and case to save weight. Some suggested the Soekris net4511 or similar. It's got a low-power 486 chip, serial ports, ethernet ports, and a PCMCIA slot for your wireless card. Or, you could hack up an existing 802.11b accesspoint to run linux and use its console port to connect to the camera. (Note: The Eumitcom-based APs are getting hard to find now. Not a platform with future potential.) There's a similar project for the Apple Airport base station, but it's limited to etherbooting, probably not suitable for this application.
You could use a pair of Ricochet modems dialed to each other (auto-answer on the chopper, and dial from the ground), in which case they simp
Why not just move the research to Freenet? It has the tools for information sharing in a completely free environment. The Frost messageboard software, which runs on top of Freenet, already has an xbox board with some activity in it.
Eddie was pissed when I dropped my Toughbook down his stairs. Luckily, further examination revealed that the stairs had only taken 3 small dents, none of which were obvious to the casual observer.
The toughbook, of course, failed to notice.
Why would you carry around a computer that's so delicate you can't even nudge it off a table 40 or 50 times? It's just silly when your $1700 computer is less durable than a $30 dead-tree book. Don't put up with wimpy hardware.
Canon has used ultrasonic piezoelectric motors in their lenses for years. These are the "mexican wave" (wtf?) motors that the New Scientist article mentions. I'm not sure why they'd be any more expensive than the origami motors described here.
Piezoelectric stick-slip actuators are nothing new. Those units built at Cambridge apparently pre-date the units mentioned in the article, but the surface preparation technique is somewhat different.
I've seen these little "on the phone!" lights sold in the same catalogs that sell handset kits for desk phones and stuff like that. You could easily use white stencils or white-on-clear labels to make one into a nice little "on air" light for yourself.
Of course, be sure to turn it off once in a while. You don't want to be the boy who cried "do not disturb".
Not even in the lunchroom! Jeebus, that stuff reeks. There should be a special microwave, outside under an awning where the smokers sit, specifically for popcorn. It should be popped, shaken, opened, aired-out, and half eaten before bringing it indoors.
Waving your smelly popcorn in my airspace is an invitation for me to overindulge on burritos tonight, and tomrrow spend a lot of time inspecting the bulletin board right next to your cubicle.
Ditto on the perfume thing, people don't realize how intensely that stuff smells. I used to know when one particular secretary was in the office because I'd start sneezing in the hallway.
HVAC contractors frequently install fake thermostats so people can enjoy the placebo effect of twisting a knob, without actually changing the temperature. The real t-stat is in the hallway near the boss's office, of course.
GotchaNOW! is automatic motion-monitoring webcam software. They've got several testimonials from when gotchanow recorded someone stealing office supplies, etc... Unfortunately, it's payware.
You're right that optical media, or anything that rotates only when being accessed, is very secure in the event that the machine takes a hit while the media is in the drive. For this reason, you might want to keep the CD-RW drives in the machines even if you're using a different technique for nightly backup, and do weekly backups to an RW disc or something.
A USB flash device, left plugged in to the machine for days at a time, would be connected to the PC's power supply during such a strike and might sustain damage. However, there are USB surge protectors made by several companies, they're just not super cheap. (Personally, I'd throw a $2 16V MOV across VCC and GND, and call it a day.)
Look at the costs before selecting a keychain drive. You might be able to get a USB-CF reader, and a large CF card, cheaper than a straight USB keychain drive.
Why exactly are you worried about lightning anyway? I'm sure you've got a surge protector on the AC power input.. are these machines connected to a lot of weird interfaces that would be impractical to put protection on? I'm imagining a warehouse environment where RS232 links and stuff might make things difficult, but B&B makes surge protectors for just about every interface you can imagine. APC has a pretty wide selection of surge protectors too.
If the threat model didn't include "massive jolt frying everything in the box", you could get away with some much cheaper backup solutions. Get a batch of surplus or refurb hard drives. They're cheap in single quantities, and practically free if you buy by the crate! Set your software to spin the drive down except during the nightly backup run. This reduces the chances of all sorts of failures, including data corruption risks caused by power glitches during operation.
I don't know if it would be of any use to your application, but having a ten-gig backup device means you could keep old backups for quite a while before reusing the space.
The hot-swap features are dubious. They technically won't hurt the drive, but your OS will be royally pissed at you if you yank a drive right off an IDE chain. Particularly if it was jumpered as Master.
There's a simple solution, though: USB/Firewire external drives have support in the drivers for hot connection and disconnection. Usually you have to click an icon to tell the drivers to prepare, but after a moment you'll be permitted to remove such a device. "But!", you say, "that's an extra power supply and an extra case sitting around!"
"Not so fast", I reply. You can combine the drive-bay-mounted removable racks that we all know and love, with the hot insertion and removal of USB or Firewire! Check out this one which I particularly like because of the easy availability of extra trays.
That model is USB2.0 capable, but of course all such devices are USB1.1 backwards compatible, so if your motherboard has a 1.1 controller and you're only backing up a bit of data, there's no need to buy a 2.0 controller.
I've used "PC Inspector File Recovery" with great success in recovering files from a smartmedia card that I accidentally deleted from the camera's interface. Compactflash should be similar.
CF cards shouldn't get wet! They have plenty of space inside for moisture to linger. You got lucky. If I got a CF card wet and it didn't work after blowing the holes dry, I'd crack it open and rinse the innards with alcohol, then try again. I've got pics of the insides of a CF card on my photo gallery under the Tech album.
For those who want to attach CF cards directly to IDE controllers, adapters are available.
If someone wants to insert this into Freenet and post the CHK, all other mirrors will pale in comparison.
For the first few minutes things were fine, my ISP was still up when I decided to shut down early, rather than running the UPS battery down hard. Cell phones were fine too, for a couple hours.
Later Thursday night I tried to get back online from my laptop, and my local ISP (who uses Megapop for dialin ports) would answer and connect, I'd get an IP address, but my packets went nowhere. Tracert stopped at hop 1.
So, knowing that the phone system was up, I simply dialed out of the affected area. Calling a POP in another city worked fine, and I was able to touch base with a few friends online before the laptop battery gave out.
Friday morning, having recharged the laptop in the car, I gave it another go. This time, the far-away ISP connected but wouldn't route packets. I decided it wasn't very important, that the fridge wouldn't stay cold much longer, and I gave up on the internet in favor of starting the generator.
Megapop: B for staying up as long as they did, F for eventually failing. Big batteries followed by dead generator? Final grade, low D.
When I signed up with Nextel as a cell phone carrier, I did so with the knowledge that their history had been as a mobile radio provider to law enforcement and public safety agencies. I figured if anyone's network would be well engineered, it would be theirs. Oops.
For the first few hours, my phone said it could see the tower, but circuits were predictably busy. That's understandable. Then some time Thursday evening the tower went off the air, and didn't come back until Friday afternoon, for 2 hours, then it disappeared again. I took to checking my voicemail from a POTS line. During the next day I got and lost signal several times, including one weird moment when the phone's light blinked red (It's only supposed to know solid red or blinking green) and the display said "Ready", instead of "NEXTEL".
Starting Thursday afternoon, my (quite expensive) Packetstream service was useless. Even when I could make voice calls, the internet was unreachable. This has me really baffled. The cell site was up, but something at the back-end was down? If anything, I'd expect their switching facilities to be better protected than the individual sites! I'm cancelling Packetstream in favor of the much cheaper and probably equally unreliable data service from T-Mobile.
Nextel: C- for unreliable service starting immediately, F for getting even worse after that. Shame on you.
POTS remained working perfectly the whole time, despite the fact that I know my line to be carried through a SLIC-hut. Those batteries did exceptionally well. Except for the first busy hour following the blackout when everybody called around to check up on family, I never had problems making calls. After replacing all the cordless phones in the house with corded models, life returned to a sweaty version of normal. Curiously enough, one of our three POTS lines failed midway through the outage, and didn't come back until late Sunday. Coincidental failure?
SBC: A for having dialtone the whole time, B+ for only giving "all circuits busy" messages a few times under what must have been heavy load.
I'd bet otherwise. The local telco's CO has 18+ hours of battery and a week of diesel/kerosene, and they test-run their turbine every 6 months to make sure it can carry the load. CO's just don't go down, the uptime of switches is measured in decades, and most offices have never had a power hit on the equipment side.
It's possible that your line doesn't come straight from the CO, rather it hops through a remote equipment location (a "hut" or "vault"), which has batteries but no generator.
Huts, vaults, and cellular base stations aren't considered big enough to deserve their own generators, but they have big sockets outside, where a trailer-mounted generator can be plugged in. Unfortunately, nobody plans for all however-many-thousand sites to be off the grid at the same time, and there are usually only 2 or 3 techs with trucks towing generators around for any given region.
It's also possible that your circuits aren't carried on copper at all. If you have more than 4 T-1's, it's more economical to bring them in on a fiber loop than maintaining a bunch of T-1 spans. An OC-3 ring can carry 3 DS3 (T-3) circuits, or 84 DS1 (T-1) circuits. Therefore, such a ring will usually leave the CO and wander through town, with "nodes" in many different customers' buildings before returning to the CO. Each node on customer premises lives in a big blue cabinet, with batteries at the bottom which will sustain it for a few hours. SONET ring architecture is such that a single failure doesn't kill traffic, but if nodes on either side of you fail, you're isolated.
Without knowing more about your situation, this is all I can say, but I'm very certain that the C.O. never lost battery.