One end USB HID device, other end lots (up to 50) of I/O pins, either freely programmable or with functions like LCD, I2C, SPI, IR RC5, LCD, LED matrix, keyboard matrix. There are also variants that can work as USB Joystick, USB Keyboard, USB Mouse.
Have a good boss. Really. He doesn't have to be the nice guy everybody loves. That probably won't help. His real job is to keep the management's political games away from the developers, and to translate between nerds and managers. Most times, your ideal boss will seem just to do some paper work, and not mess with nerds' stuff. From time to time, he will ask how far the project has progressed, and occasionally, he will tell you that the stuff really has do be done before a certain deadline, at least so far that the stuff does not crash within the first five minutes. And when things are really burning, he's the one that listens to you when you need someone to yell at.
That was my first boss, and I still miss his talents. My current boss is a moron. No clue of management and politics in management, no clue of project management, hardly a clue of software development, but he knows his computer well enough to find mouse, keyboard and power button. Unfortunately, this makes him think he could manage and administrate computers. And, my absolute favorite, his completely irrational optimism. If he would drive at 200 mph against a solid wall, his last words would be "I'm perfectly optimistic that I will survive the crash without a single scratch".
The most important thing: Keep end-user support away from developers. Nothing kills concentration more than a phone that rings every few minutes, with a completely clueless user on the other end of the line, telling you that his "computer does not work, and it's all your fault".
And, you may have already guessed that: My current boss forces me to support end-users, during development.
Yes. While DSL, UMTS and DOCSIS are quite common in urban areas, there are still several areas (villages) where dual-channel ISDN is the fastest way to get into the net (2x 64 kBit/s), and many people in those areas still use analog modems (V.90) simply because ISDN lines have a higher monthly fee and dual channel ISDN doubles the costs of each internet connection.
Of course, there is also satellite internet access, but it is expensive, overloaded, slow (despite opposite claims of the operators) and has a high latency. Plus, you need a free line of sight to the satellite and the permission to install a(n additional) satellite dish from the owner of the house. LTE is the latest promise for fast internet access in non-urban areas, following WiMAX. WiMAX exists only in prototype areas, it still is not commonly available in Germany. LTE is only planned, no prototype area exists, and despite legal restraints to install LTE first in areas without high speed internet connections, the first prototype areas will be big cities.
Another reason to use a modem is the ability to send and receive faxes, as others already posted.
Costs for 0900 calls are very high compared to other numbers, and the 0900 owner can define how much is charged. There are two mutually exclusive limits: Either max. 3.00 EUR per minute, or max. 10.00 EUR per call independantly from the length of the call. (Source: http://www.teltarif.de/i/sonderrufnummern-0900.html) So if you use the second option (charge 10.00 EUR per call) and distribute a dialer that makes one-second calls to your 0900 number, you gain 10.00 EUR per second and call. Gaining 8,000,000 EUR (roughly approximating 1 EUR = 1 $) requires 800,000 calls. If you can make 10 calls before getting caught by the modem owner, you need only 80,000 users. If you can make 100 calls before getting caught, you need just 8,000 users.
ISDN users are even more attractive than modem users. The V.90 handshake needs about 10 to 20 seconds, and it is noisy due to the modem speaker. Plus, the V.90 modem blocks the phone line. So it is very likely that the dialer is found very fast. The ISDN handshake takes much less time, about a second, it is silent, and ISDN offers two lines, so you can still use your phone while your computer is busy wasting your money with one second calls to a 0900 line. If that goes unnoticed for one hour, and each call lasts four seconds total, you have 900 calls from one user, 9,000 EUR. Trick just 900 users into using your dialler for one hour on an ISDN line and you gain 8,100,000 EUR.
Come on, this must be an April fools joke released too early!
The site is unusuable without Javascript, can't even configure without JS, no way to switch back to classic layout, lots of broken links (at least w/o JS), and the usual boring "look Ma, I can do round corners, shadows and non-scrolling sections on my web 2.0 site" shit. There is one thing that everyone writing a web site should know in 2011: Javascript is OPTIONAL. Make sure the page works 100% without Javascript. And by the way: In 2011, you should be able to produce valid HTML, encoded in UTF8. Even when working with templates. Especially when you pretend that the site is HTML5.
... in my last job, we had a lot of clients using Microsofts mail services. M$ gave you basically two choices: Implement SPF or have your mails delivered to the spam folder or refused. So, we made our DNS provider add SPF records and the problem was gone.
... you just need to know that your friends (and family members) DO NOT need to mess with their routers. Just YOUR router needs to open a single port (5500/tcp) and forward it to your workstation. Make your friends run the VNC server as usual, start the VNC client on your workstation in LISTENER mode, tell your friends to select "add new client" from the VNC server icon context menu, and make them enter your IP or dyndns address into the popup dialog.
(Technically, this swaps the roles of client and server on the TCP level, but VNC still behaves as expected.)
NTFS and ext3 have journaling, FAT12/16/32 and ext2 don't have journaling.
FAT12/16/32 have a central structure (the FAT). Damage it and your data is lost. ext2 and ext3 store their meta data redundantly.
RAID is no replacement for Backup.
A real hardware RAID is expensive, and appears to be a single disk to both BIOS and OS. Its on-disk meta data is propritary, i.e. if your HW RAID controller dies, you need exactly the same controller again to get access to your data. HW RAID works with every OS, because it appears to be a single disk (typically, SCSI). Booting from complex RAID configurations is no problem, as each RAID appears to be a single disk. The RAID controller is a small computer on its own, taking care of the reqired calculations for non-trivial RAID levels, of switching to hot-standby disks, and of detecting broken disks.
A software RAID is cheep as dirt, every single disk of the RAID appears in BIOS and lower levels of the OS. The on-disk meta data depends only on the OS, so you can mix controllers as you like. A broken controller is no problem, replace it with any controller that has the same connectors and your data is back. Booting can be a problem, because the BIOS does not know anything about the RAID. Usually, booting is only possible for RAID-0 and RAID-1. Booting another OS is problematic, because there is no standard for Software RAIDs. Linux may be able to work with Windows RAID volumes, but Windows can't work with Linux RAID volumes. Calculation and monitoring is done by the host CPU.
A host RAID is nearly as cheep, the only difference to a software RAID is that the BIOS decides about the on-disk meta data. Special drivers for each supported OS know the structure of the meta-data, but they don't allow to use other controllers in the same RAID. A broken controller is a problem, because drivers will refuse to work with other controllers. Booting is no problem, because the BIOS knows about the RAID.
I prefer pure software RAIDs, for a simple reason: They do not depend on available hardware. If one controller dies, switch to another one: Other brand, other type, other drivers, and the RAID still works. If you insist, you can even mix an IDE drive, a USB drive, a SATA drive and a SCSI drive into a single RAID. Try that with a hardware or host RAID. Some people even built RAIDs of floppy disks or USB sticks (not for pemanent use, of course).
My faithful old Linux home server runs two RAIDs, both in software: a RAID-1 for the OS (remember: the BIOS does not know about the RAID), and a RAID-5 for the data. The RAID-1 used to run on old SCA drives, but recently, I switched to two small IDE drives due to unrecoverable SCA cabling problems. The RAID-5 is composed of four IDE drives, connected to two IDE controllers, each disk on a single IDE cable. An external USB disk is used to back up my data, rotating through 10 days. All filesystems are ext3, all disks are monitored using SMART, all RAIDs are monitored. If anything wents wrong, I will get an e-mail from the monitoring software.
Until recently, one of the controllers was an el-cheapo non-RAID controller, and the other one was a donated, expensive, well-known brand, RAID-capable controller running in non-RAID mode. The latter one decided to randomly take some free time on the job, and either disconnected from the PCI bus or disturbed it, causing panics in the OS above. Only pure luck protected me from data loss. I ripped it out of the machine, kicked it into the trash bin, rewired the RAID to use two disks per IDE cable, and verified and reconstructed my data. Some days later, another el-cheapo non-RAID IDE controller arrived, the same brand, model and type that already sat in the next PCI slot. So I rewired the RAID again to work with one disk per cable, everything was fine again.
For a new small business or home server, I would use nearly the same setup again: Two software RAIDs, one for the OS, and one for the data. Upgrading the OS is just fun when you can
It is called "GEZ Gebühr" (fee for the GEZ, the Gebühreneinzugszentrale - Central for fee collecting, a divison of the public broadcast services ARD and ZDF), everyone in Germany has to pay the GEZ fee to receive radio broadcasts (reduced fee, about 5 Euro per month) or TV and radio broadcasts (full fee, about 15 Euro per month). It does not depend on the number of devices, you have to pay 15 Euro no matter if you own one TV set or 10.000. Some group of persons may apply for exemption.
The original idea of the "internet fee" was that you could receive internet streams from the websites of the public broadcast services with an internet capable device (not only PCs, but also UMTS mobile phones), so a PC would be equal to a TV set (yes, that's how german politicans think) and you have to pay the full GEZ fee. It simply does not matter if you actually do receive those streams, all that counts is that you are able to recevie them.
After lots of complaints from nearly every organisation, the "internet fee" was changed to the reduced radio fee. This does not affect common households, because they usually already pay for receiving radio and TV broadcasts, so the PC is "just another TV set". But each and every company that uses even only one PC now has to pay 5 Euro per month for the ability(!) to receive TV and radio broadcasts via internet. A related information: The german tax authorities force you to use an internet capable PC for your monthly tax declaration, so nearly every company now has to pay the GEZ fee.
Tux2000, nearly becoming mad during the attempt to translate this nonsense into english
I use an ugly HP LJ 1200N for my home office. The "N" indicates two things for this model: an external, ugly HP Jetdirect USB print server powered from an external power supply, and 16 MBytes RAM instead of 8 MBytes. I found that upgrading the RAM to 32 MBytes (ripped out of a dead LJ 8500) makes it a little bit more responsive. A refurbished 1200N would fit into your budget, at about $300 according to cnet. A new toner cartridge costs about $65 for 2500 pages, $80 for 3500 pages if you buy from HP, $40 or less if you use a 3rd party cartridge.
There is also a 1220 model with a scanner on top of the printer. HP has replaced the 1200 series with the 1300 series.
I know the HP LJ 4000 Series (4000N, 4050N, 4100N) from my former employeer, they are very reliable until someone tortures it with inkjet overhead transparancy films. Their big advantages over the 1200 are the build-in print server, a completely closed paper cartridge below the printer, a button to cancel a print job running amok, and they need less space on the table than the 1200, because of the paper cartridges and the build-in print server. After two or three years (several 10.000 pages), they needed a new kit of paper wheels, easy to swap and low cost. And once a year, someone came to clean the printers from paper and toner dust.
Whatever printer you buy, think about buying a printer with a Postscript interpreter. I can use my 1200 (with Postscript) from each and every computer I own, even without manufacturer-supplied drivers, simply because all of my computers are able to create Postscript output. Compare that with a "GDI printer", where the printer driver does the job of putting pixels onto the paper. If you have no driver, you can not print. Will Windows Vista include support for your GDI printer? Perhaps not. Will the printer manufacturer deliver a driver for Vista? Perhaps not. Will the old driver work with Vista? Perhaps not. Will the printer work with the next iteration of Windows? Perhaps not. Will Vista be able to generate Postscript? Yes. Will it work with my 1200? Yes. A related example: Windows 98 supported all features of the Soundblaster AWE32, Windows 2000 detects it as a Soundblaster 16, no AWE features available. Creative does not deliver a driver for Windows 2000, but recommends to replace a working device with a new device.
Why does each server has its own UPS? Use a single UPS with more power. To notify all machines about a power outage or a low battery state, use either a special distribution box from the UPS manufacturer, or make one server the "UPS master" and let it notify the other servers via ethernet. (Connect the ethernet switch to the UPS.) Have a look at http://www.apcupsd.com/ for a free (as in speak and as in beer) solution that works not only with APC UPSes.
Why do you need three servers? One more powerful machine and some virtualisation software could emulate the three servers. Such software is available for free (as in beer). That would also solve the UPS notification problem, because only the host OS has to be notified.
Separate servers and user(s). You simply cannot work in a room where at least three servers and a UPS generate noise and heat. And the machines can't, either. You need an air conditioning system to cool down the machines, so you get even more noise. Put the servers into a separate room, perhaps a broom closet or into the basement. At least, use some wood and a folding door to separate a small part of the room from the rest for the servers, that's what I did in my home office. Folding doors aren't the perfect noise guard, but they attenuate the noise a little bit, especially the high frequencies.
Think about housing the three servers at some hosting provider, that gives you a reliable power supply without your own UPSes and air conditioning for the servers. Use a high-bandwith connection and VPN and you do not need more room than a single ethernet socket for any amount of servers.
Just drop your RFID-contaminated passport into a microwave oven and turn the oven on for a few seconds. Tadaa!, toasted RFID chip with no visible sign of manipulation.
Even worse, assume someone is able to gain access to the child porn database. Child porn distributed by a big ISP is a real nightmare, not only for the ISP.
Let's hope that some detail has been lost: A database with some kind of hash sum of the images (and *not* the images themselves) would be a good idea. The big problem is to identify images (and videos) without (or with a very low rate of) false positives and false negatives. There are known ways to bypass simple file checksum algorithms: Append some junk bytes, recompress, rotate, mirror, and so on. The hash sum algorithm has to be able to detect this. The images could be packed into archives or iso files, and so on. There are nearly infinite possibilities to bypass blacklist filters. I won't go into details, for obvious reasons.
The "Zeroth Law" (from Robots and Empire) is "A robot may not injure humanity or, through inaction, allow humanity to come to harm." It is not acceptable by all robots, only by the most advanced. It was developed by R. Giskard and R. Daneel, not by humans.
If you like, you may interpret this accident as protected by the zeroth law...
How I write web pages (and web applications): Code it, open in Opera, look for obvious errors, hit Ctrl-Alt-V to validate the page using the W3C validator. If W3C says the page is valid HTML, my work on that page is done. Else, fix what the validator marks as wrong. If a browser can't render the final page properly, the browser is broken, not my page. I don't have to test my page for hours with a heap of browsers, some quick validator runs are all I need.
No, I'm not a web designer. I prefer pages that can be scaled up and down using the browser settings, as preferred by the user. I prefer simple, formatted text (simple HTML, perhaps without CSS) to webpages that torture the browser into a pixel resolution grid. Those pages are easily written, easily validated, easily rendered, and look pretty good in all browsers.
Dr. Zefram Cochrane (James Cromwell) from Star Trek: First Contact. After 30 years of hero worship for Zefram Cochrane in the various series and movies, this Zefram Cochrane is finally not the typical Einstein-style geek scientist.
(No, I won't explain the plot. If you read slashdot without knowing that film, you must come from another planet. Welcome on earth.)
I use pen and paper for a large part of my job: Notes, ideas, tracking working hours, appointments. No cables, no empty batteries, no chargers, weights less than a PDA and can be bent without loss of data. What else does a PDA offer? A calculator - also offered by my cell phone, and my brain can also shuffle around some numbers. A phone book? In my cell phone, and more convienient. E-Mail addresses? On my laptop. "Pocket Office"? A full-featured office package runs on my laptop. MP3 player? On my laptop. Perhaps, some day, I may buy an iPod.
I use an old (should I say antique) Nokia 5130 cell phone with a third party li-ion battery, giving me at least a week runtime without needing a charger. When I'm longer away from home, I can pack the small charger somewhere into my luggage; when I travel by car, the handsfree car kit charges the cell phone battery. And a second cell phone "as backup" is just nonsense. The last time a 5130 refused to work was when it fell into a bucket full with dirty soap water, about five years ago. It has no camera, no color display, no "screensaver", no fancy ringtones, it can't even show a custom logo. But I can use it to call people. That's why I bought it.
Sure, I also need to work with a laptop, but I don't carry a PVR around. Why should I want to do that?
I also have a GPS for my car, based on a cheap PDA, but that stays either at home in its cradle or in a locked box inside the car. I don't need the PDA features, just the GPS software. Inside the car, the PDA is powered by the car. So I don't need to carry around a charger. The cradle stays at home. The GPS software does not need to be backed up or synced, so I use the cradle just as a charger. The USB cable is plugged nowhere.
... just wait until I find some pictures of my granny naked at the age of 80 that I can hang in front of the camera, covering the entire lens. You want to add a microphone? Sure, if you want me to add a headphone and an mp3 player playing an endless loop of my entire modem handshake sound collection.;-)
Microsoft included a virus scanner already in MS DOS 6.00, released 1993. They also offered one or two updates during the lifetime of MS DOS. "Nice try, better luck next time" was the common answer. The other AV software (like McAfee) was simply much better, faster and simply up-to-date.
I doubt Microsoft will do it better this time. Sure, they finally learned that you have to update your OS and some major applications. But they decided to distribute the updates not when the updates are ready, but when the regular patch-day happens. Bad luck if the update is not ready at that point. In 1993, experts recommended to update the AV software weekly or at least monthly. Now, we are told to update the AV software at least daily. The AV software I use checks for updates every eight hours by default. IMHO, that's simply too fast for Microsoft. My guess is they won't release more than one update per week for the scanner, and I think they will do it via the Windows update service.
"Managing programmers is like herding cats", so think "cats":
Cats love NEW toys, so do many programmers. All this shiny new stuff with those shiny cases, fancy buttons, wheels, displays, and new features (drool). If you can't give them the money, give them their new toys. Some toys that may be useful later (like a new compact PC or a hackable NAS), some toys that are just for their private fun (like iPods, but they are OLD toys). Look at thinkgeek.com for a lot of toys...
Relaxed dress code. Do you know those old ladys carrying their mini-dogs in fancy dresses (dog-cinderella, dog-ballerina, dog-barbie,...)? Did you ever see a cat wearing such a stupid dress (for more than 5 minutes)? Allow (almost) any dress that covers the private parts, because pin striped suits are at least as stupid as those dog ballerina dresses for real programmers.
Cats aren't always hunting, they spend a lot time of the day relaxing. For me, having some time for surfing slashdot.org, heise.de, freshmeat.net, and cpan.org is very relaxing, and I always took that time.
Cats can play with almost anything, sometimes, a leaf can be a toy for half an hour. Allow smaller, private projects. I built a web-controlled FM radio from an ISA radio card, an old PC and some Linux tools. It is now running for years and anyone in the team can control it from his computer.
Also have a look at Googles way of motivating their "cats".
One line output driving a bundle of line inputs: works, but not good (impedance problems, ground loops unless you use symmetrical inputs, cables and output)
One amplifier output driving a bundle of speakers: too many speakers kill the amplifier (impedance goes too low), lots of loss on long cables. Driving a 4 ohm speaker via a long, thin cable having 2 ohm per wire uses half of the power to heat the cable.
The standard technique for distributing audio to a bunch of speakers is to use 100 volts (I don't know about USA, I've read another comment about 25 volts, which seems to be the same trick on an idiot-proof voltage level). Nearly all super markets that I know use 100 V sound distribution for the background music and anouncements. The power amplifier drives the line with 100 volts at maximum output (usually using an output transformer), each speaker has a transformer that matches 100 volts to the power and impedance of the speaker. This sounds like a hifi enthusiasts nightmare, but it sounds pretty good when done right. There are several benefits: You can not kill a 100 V / 10 W speaker with a 100 V / 1000 W amplifier at full power, it will simply emit 10 W. (But a 100 V / 10 W amplifier will be killed by a 100 V / 1000 W speaker.) The high voltage makes wire resistance nearly irrelevant, you can wire 100 V sound as you would wire light bulbs. You can even use the same switches. Most speaker transformers have several inputs, allowing you to reduce the volume by switching to another input. There are also wall-mount potentiometers to adjust the volume, but they trade volume for heat. The main disadvantage is pretty obvious: You need one transformer per channel in or behind your amplifier, and one transformer per speaker. You can add the transformers to common hifi equipment, but there are also professional amplifiers with build-in transformers, usually rack mounted, and professional wall-mounted or ceiling-mounted speakers with transformers. At least the latter will kill your budget.
If your house does not have much metal inside the walls, i.e. if you can use one set of wireless speakers even through several walls, you could buy several identical sets, one set for each room. Set up all receivers (speakers) to "listen" to the same transmitter, connected to your PC. No cables (except for the speaker's power line), no impedance trouble, but depending on the quality of the sets, you may have some RF interferences (especially with a mobile phone nearby).
There are power line audio distribution systems (Devolo is very popular in Germany). You run a wire from your PC to a wall brick, that modulates your audio signal onto a HF carrier, and injects it into your power line. Other wall bricks in other rooms filter the HF carrier from your power line and demodulate the audio signal. Another wire runs from the brick to some amplified speakers. Like before, no cables, no impedance trouble. No RF interfaces, but the Develo bricks may kill your budget.
The best protection for any kind of application you hand over to a customer is a clear license agreement stating what is allowed and what not, together with a good lawyer. It is probably the best way to make the lawyer write the license agreement together with you.
Just as a good hint for you and your customer(s), you may digitally sign your code with a private key (using PGP or similar). Refuse any kind of support when the signature validation fails, i.e. the code is modified. Think of it as a "warranty void if seal broken" in code. Don't check the signature in the code, this is just stupid. The first step of modifying your code would be to remove the signature checker. The signature checker is a separate application on your computer(s) that you do not give away. It may be just a simple shell script using PGP and your public key.
Don't even think about encrypting your code, this is plain stupid. Your application needs to know how to decrypt the code, and the decryption engine must be unencrypted to run. So with a minimal modification of the decryption engine, your customer can read your code anyway. A binary decryption engine (XS in Perl) is not directly readable, but it makes the job just a little bit harder. There are decompilers out there.
Tux2000 <- gave away 100.000 lines of code to paying customers, multiple times
Impressive, but not really useful for daily use. I know the first 11 digits, that's more than enough if I have to use a cheap calculator without PI and trigonometric functions.
For common daily calculations, knowing 3.14 or 3.1416 (rounded!) is usually sufficient:
The german car taxes are calculated based on the volume of the engine, calculated with PI = 3.14. This (technically wrong) value is also written into the vehicle registration certificate, with three to five digits. The calculation rule origins to the the time after WW II, when most calculations were done on paper. Using only three digits of PI instead of six, eight, or ten reduced the amount of work and caused only a negligible error (less than 1%).
Slashdot Mirror
Peter principle
IO-Warrior:
One end USB HID device, other end lots (up to 50) of I/O pins, either freely programmable or with functions like LCD, I2C, SPI, IR RC5, LCD, LED matrix, keyboard matrix. There are also variants that can work as USB Joystick, USB Keyboard, USB Mouse.
Tux2000
Have a good boss. Really. He doesn't have to be the nice guy everybody loves. That probably won't help. His real job is to keep the management's political games away from the developers, and to translate between nerds and managers. Most times, your ideal boss will seem just to do some paper work, and not mess with nerds' stuff. From time to time, he will ask how far the project has progressed, and occasionally, he will tell you that the stuff really has do be done before a certain deadline, at least so far that the stuff does not crash within the first five minutes. And when things are really burning, he's the one that listens to you when you need someone to yell at.
That was my first boss, and I still miss his talents. My current boss is a moron. No clue of management and politics in management, no clue of project management, hardly a clue of software development, but he knows his computer well enough to find mouse, keyboard and power button. Unfortunately, this makes him think he could manage and administrate computers. And, my absolute favorite, his completely irrational optimism. If he would drive at 200 mph against a solid wall, his last words would be "I'm perfectly optimistic that I will survive the crash without a single scratch".
The most important thing: Keep end-user support away from developers. Nothing kills concentration more than a phone that rings every few minutes, with a completely clueless user on the other end of the line, telling you that his "computer does not work, and it's all your fault".
And, you may have already guessed that: My current boss forces me to support end-users, during development.
Tux2000
Yes. While DSL, UMTS and DOCSIS are quite common in urban areas, there are still several areas (villages) where dual-channel ISDN is the fastest way to get into the net (2x 64 kBit/s), and many people in those areas still use analog modems (V.90) simply because ISDN lines have a higher monthly fee and dual channel ISDN doubles the costs of each internet connection.
Of course, there is also satellite internet access, but it is expensive, overloaded, slow (despite opposite claims of the operators) and has a high latency. Plus, you need a free line of sight to the satellite and the permission to install a(n additional) satellite dish from the owner of the house. LTE is the latest promise for fast internet access in non-urban areas, following WiMAX. WiMAX exists only in prototype areas, it still is not commonly available in Germany. LTE is only planned, no prototype area exists, and despite legal restraints to install LTE first in areas without high speed internet connections, the first prototype areas will be big cities.
Another reason to use a modem is the ability to send and receive faxes, as others already posted.
Costs for 0900 calls are very high compared to other numbers, and the 0900 owner can define how much is charged. There are two mutually exclusive limits: Either max. 3.00 EUR per minute, or max. 10.00 EUR per call independantly from the length of the call. (Source: http://www.teltarif.de/i/sonderrufnummern-0900.html) So if you use the second option (charge 10.00 EUR per call) and distribute a dialer that makes one-second calls to your 0900 number, you gain 10.00 EUR per second and call. Gaining 8,000,000 EUR (roughly approximating 1 EUR = 1 $) requires 800,000 calls. If you can make 10 calls before getting caught by the modem owner, you need only 80,000 users. If you can make 100 calls before getting caught, you need just 8,000 users.
ISDN users are even more attractive than modem users. The V.90 handshake needs about 10 to 20 seconds, and it is noisy due to the modem speaker. Plus, the V.90 modem blocks the phone line. So it is very likely that the dialer is found very fast. The ISDN handshake takes much less time, about a second, it is silent, and ISDN offers two lines, so you can still use your phone while your computer is busy wasting your money with one second calls to a 0900 line. If that goes unnoticed for one hour, and each call lasts four seconds total, you have 900 calls from one user, 9,000 EUR. Trick just 900 users into using your dialler for one hour on an ISDN line and you gain 8,100,000 EUR.
Tux2000
Come on, this must be an April fools joke released too early!
The site is unusuable without Javascript, can't even configure without JS, no way to switch back to classic layout, lots of broken links (at least w/o JS), and the usual boring "look Ma, I can do round corners, shadows and non-scrolling sections on my web 2.0 site" shit. There is one thing that everyone writing a web site should know in 2011: Javascript is OPTIONAL. Make sure the page works 100% without Javascript. And by the way: In 2011, you should be able to produce valid HTML, encoded in UTF8. Even when working with templates. Especially when you pretend that the site is HTML5.
Summary: Slashdot new design = BIG FAIL!
Tux2000
... in my last job, we had a lot of clients using Microsofts mail services. M$ gave you basically two choices: Implement SPF or have your mails delivered to the spam folder or refused. So, we made our DNS provider add SPF records and the problem was gone.
Tux2000
... you just need to know that your friends (and family members) DO NOT need to mess with their routers. Just YOUR router needs to open a single port (5500/tcp) and forward it to your workstation. Make your friends run the VNC server as usual, start the VNC client on your workstation in LISTENER mode, tell your friends to select "add new client" from the VNC server icon context menu, and make them enter your IP or dyndns address into the popup dialog.
(Technically, this swaps the roles of client and server on the TCP level, but VNC still behaves as expected.)
Tux2000
Fast facts:
I prefer pure software RAIDs, for a simple reason: They do not depend on available hardware. If one controller dies, switch to another one: Other brand, other type, other drivers, and the RAID still works. If you insist, you can even mix an IDE drive, a USB drive, a SATA drive and a SCSI drive into a single RAID. Try that with a hardware or host RAID. Some people even built RAIDs of floppy disks or USB sticks (not for pemanent use, of course).
My faithful old Linux home server runs two RAIDs, both in software: a RAID-1 for the OS (remember: the BIOS does not know about the RAID), and a RAID-5 for the data. The RAID-1 used to run on old SCA drives, but recently, I switched to two small IDE drives due to unrecoverable SCA cabling problems. The RAID-5 is composed of four IDE drives, connected to two IDE controllers, each disk on a single IDE cable. An external USB disk is used to back up my data, rotating through 10 days. All filesystems are ext3, all disks are monitored using SMART, all RAIDs are monitored. If anything wents wrong, I will get an e-mail from the monitoring software.
Until recently, one of the controllers was an el-cheapo non-RAID controller, and the other one was a donated, expensive, well-known brand, RAID-capable controller running in non-RAID mode. The latter one decided to randomly take some free time on the job, and either disconnected from the PCI bus or disturbed it, causing panics in the OS above. Only pure luck protected me from data loss. I ripped it out of the machine, kicked it into the trash bin, rewired the RAID to use two disks per IDE cable, and verified and reconstructed my data. Some days later, another el-cheapo non-RAID IDE controller arrived, the same brand, model and type that already sat in the next PCI slot. So I rewired the RAID again to work with one disk per cable, everything was fine again.
For a new small business or home server, I would use nearly the same setup again: Two software RAIDs, one for the OS, and one for the data. Upgrading the OS is just fun when you can
Joe has just met someone from the GEZ ... (who, by the way, is being paid a bonus for each and every TV not yet registered with the GEZ)
Tux2000
It is called "GEZ Gebühr" (fee for the GEZ, the Gebühreneinzugszentrale - Central for fee collecting, a divison of the public broadcast services ARD and ZDF), everyone in Germany has to pay the GEZ fee to receive radio broadcasts (reduced fee, about 5 Euro per month) or TV and radio broadcasts (full fee, about 15 Euro per month). It does not depend on the number of devices, you have to pay 15 Euro no matter if you own one TV set or 10.000. Some group of persons may apply for exemption.
The original idea of the "internet fee" was that you could receive internet streams from the websites of the public broadcast services with an internet capable device (not only PCs, but also UMTS mobile phones), so a PC would be equal to a TV set (yes, that's how german politicans think) and you have to pay the full GEZ fee. It simply does not matter if you actually do receive those streams, all that counts is that you are able to recevie them.
After lots of complaints from nearly every organisation, the "internet fee" was changed to the reduced radio fee. This does not affect common households, because they usually already pay for receiving radio and TV broadcasts, so the PC is "just another TV set". But each and every company that uses even only one PC now has to pay 5 Euro per month for the ability(!) to receive TV and radio broadcasts via internet. A related information: The german tax authorities force you to use an internet capable PC for your monthly tax declaration, so nearly every company now has to pay the GEZ fee.
Tux2000, nearly becoming mad during the attempt to translate this nonsense into english
I use an ugly HP LJ 1200N for my home office. The "N" indicates two things for this model: an external, ugly HP Jetdirect USB print server powered from an external power supply, and 16 MBytes RAM instead of 8 MBytes. I found that upgrading the RAM to 32 MBytes (ripped out of a dead LJ 8500) makes it a little bit more responsive. A refurbished 1200N would fit into your budget, at about $300 according to cnet. A new toner cartridge costs about $65 for 2500 pages, $80 for 3500 pages if you buy from HP, $40 or less if you use a 3rd party cartridge.
There is also a 1220 model with a scanner on top of the printer. HP has replaced the 1200 series with the 1300 series.
I know the HP LJ 4000 Series (4000N, 4050N, 4100N) from my former employeer, they are very reliable until someone tortures it with inkjet overhead transparancy films. Their big advantages over the 1200 are the build-in print server, a completely closed paper cartridge below the printer, a button to cancel a print job running amok, and they need less space on the table than the 1200, because of the paper cartridges and the build-in print server. After two or three years (several 10.000 pages), they needed a new kit of paper wheels, easy to swap and low cost. And once a year, someone came to clean the printers from paper and toner dust.
Whatever printer you buy, think about buying a printer with a Postscript interpreter. I can use my 1200 (with Postscript) from each and every computer I own, even without manufacturer-supplied drivers, simply because all of my computers are able to create Postscript output. Compare that with a "GDI printer", where the printer driver does the job of putting pixels onto the paper. If you have no driver, you can not print. Will Windows Vista include support for your GDI printer? Perhaps not. Will the printer manufacturer deliver a driver for Vista? Perhaps not. Will the old driver work with Vista? Perhaps not. Will the printer work with the next iteration of Windows? Perhaps not. Will Vista be able to generate Postscript? Yes. Will it work with my 1200? Yes. A related example: Windows 98 supported all features of the Soundblaster AWE32, Windows 2000 detects it as a Soundblaster 16, no AWE features available. Creative does not deliver a driver for Windows 2000, but recommends to replace a working device with a new device.
Tux2000
Why does each server has its own UPS? Use a single UPS with more power. To notify all machines about a power outage or a low battery state, use either a special distribution box from the UPS manufacturer, or make one server the "UPS master" and let it notify the other servers via ethernet. (Connect the ethernet switch to the UPS.) Have a look at http://www.apcupsd.com/ for a free (as in speak and as in beer) solution that works not only with APC UPSes.
d ex.htm
Why do you need three servers? One more powerful machine and some virtualisation software could emulate the three servers. Such software is available for free (as in beer). That would also solve the UPS notification problem, because only the host OS has to be notified.
Think about alternative doors. There are doors that can be folded instead of swinging into the room, like this one: http://www.marley.de/produkte/falttueren/rapid/in
Separate servers and user(s). You simply cannot work in a room where at least three servers and a UPS generate noise and heat. And the machines can't, either. You need an air conditioning system to cool down the machines, so you get even more noise. Put the servers into a separate room, perhaps a broom closet or into the basement. At least, use some wood and a folding door to separate a small part of the room from the rest for the servers, that's what I did in my home office. Folding doors aren't the perfect noise guard, but they attenuate the noise a little bit, especially the high frequencies.
Think about housing the three servers at some hosting provider, that gives you a reliable power supply without your own UPSes and air conditioning for the servers. Use a high-bandwith connection and VPN and you do not need more room than a single ethernet socket for any amount of servers.
Tux2000
Just drop your RFID-contaminated passport into a microwave oven and turn the oven on for a few seconds. Tadaa!, toasted RFID chip with no visible sign of manipulation.
Tux2000
Even worse, assume someone is able to gain access to the child porn database. Child porn distributed by a big ISP is a real nightmare, not only for the ISP.
Let's hope that some detail has been lost: A database with some kind of hash sum of the images (and *not* the images themselves) would be a good idea. The big problem is to identify images (and videos) without (or with a very low rate of) false positives and false negatives. There are known ways to bypass simple file checksum algorithms: Append some junk bytes, recompress, rotate, mirror, and so on. The hash sum algorithm has to be able to detect this. The images could be packed into archives or iso files, and so on. There are nearly infinite possibilities to bypass blacklist filters. I won't go into details, for obvious reasons.
Tux2000
I agree, the robot was properly protected. There could have been more safety devices, but a fence and "big red switch" should be sufficient.
s 13
...
On the other hand, there are not three, but four laws of robotics: http://www.asimovonline.com/asimov_FAQ.html#serie
The "Zeroth Law" (from Robots and Empire) is "A robot may not injure humanity or, through inaction, allow humanity to come to harm." It is not acceptable by all robots, only by the most advanced. It was developed by R. Giskard and R. Daneel, not by humans.
If you like, you may interpret this accident as protected by the zeroth law
Tux2000
How I write web pages (and web applications): Code it, open in Opera, look for obvious errors, hit Ctrl-Alt-V to validate the page using the W3C validator. If W3C says the page is valid HTML, my work on that page is done. Else, fix what the validator marks as wrong. If a browser can't render the final page properly, the browser is broken, not my page. I don't have to test my page for hours with a heap of browsers, some quick validator runs are all I need.
No, I'm not a web designer. I prefer pages that can be scaled up and down using the browser settings, as preferred by the user. I prefer simple, formatted text (simple HTML, perhaps without CSS) to webpages that torture the browser into a pixel resolution grid. Those pages are easily written, easily validated, easily rendered, and look pretty good in all browsers.
Tux2000
Dr. Zefram Cochrane (James Cromwell) from Star Trek: First Contact. After 30 years of hero worship for Zefram Cochrane in the various series and movies, this Zefram Cochrane is finally not the typical Einstein-style geek scientist.
(No, I won't explain the plot. If you read slashdot without knowing that film, you must come from another planet. Welcome on earth.)
Tux2000
I use pen and paper for a large part of my job: Notes, ideas, tracking working hours, appointments. No cables, no empty batteries, no chargers, weights less than a PDA and can be bent without loss of data. What else does a PDA offer? A calculator - also offered by my cell phone, and my brain can also shuffle around some numbers. A phone book? In my cell phone, and more convienient. E-Mail addresses? On my laptop. "Pocket Office"? A full-featured office package runs on my laptop. MP3 player? On my laptop. Perhaps, some day, I may buy an iPod.
I use an old (should I say antique) Nokia 5130 cell phone with a third party li-ion battery, giving me at least a week runtime without needing a charger. When I'm longer away from home, I can pack the small charger somewhere into my luggage; when I travel by car, the handsfree car kit charges the cell phone battery. And a second cell phone "as backup" is just nonsense. The last time a 5130 refused to work was when it fell into a bucket full with dirty soap water, about five years ago. It has no camera, no color display, no "screensaver", no fancy ringtones, it can't even show a custom logo. But I can use it to call people. That's why I bought it.
Sure, I also need to work with a laptop, but I don't carry a PVR around. Why should I want to do that?
I also have a GPS for my car, based on a cheap PDA, but that stays either at home in its cradle or in a locked box inside the car. I don't need the PDA features, just the GPS software. Inside the car, the PDA is powered by the car. So I don't need to carry around a charger. The cradle stays at home. The GPS software does not need to be backed up or synced, so I use the cradle just as a charger. The USB cable is plugged nowhere.
Tux2000
It works because a lot of people are idiots.
Not idiots, but ignorant people who don't care and don't want to know how the technology works that they use.
Tux2000
... just wait until I find some pictures of my granny naked at the age of 80 that I can hang in front of the camera, covering the entire lens. You want to add a microphone? Sure, if you want me to add a headphone and an mp3 player playing an endless loop of my entire modem handshake sound collection. ;-)
Tux2000
Microsoft included a virus scanner already in MS DOS 6.00, released 1993. They also offered one or two updates during the lifetime of MS DOS. "Nice try, better luck next time" was the common answer. The other AV software (like McAfee) was simply much better, faster and simply up-to-date.
I doubt Microsoft will do it better this time. Sure, they finally learned that you have to update your OS and some major applications. But they decided to distribute the updates not when the updates are ready, but when the regular patch-day happens. Bad luck if the update is not ready at that point. In 1993, experts recommended to update the AV software weekly or at least monthly. Now, we are told to update the AV software at least daily. The AV software I use checks for updates every eight hours by default. IMHO, that's simply too fast for Microsoft. My guess is they won't release more than one update per week for the scanner, and I think they will do it via the Windows update service.
Tux2000
"Managing programmers is like herding cats", so think "cats":
Also have a look at Googles way of motivating their "cats".
Tux2000
One line output driving a bundle of line inputs: works, but not good (impedance problems, ground loops unless you use symmetrical inputs, cables and output)
One amplifier output driving a bundle of speakers: too many speakers kill the amplifier (impedance goes too low), lots of loss on long cables. Driving a 4 ohm speaker via a long, thin cable having 2 ohm per wire uses half of the power to heat the cable.
The standard technique for distributing audio to a bunch of speakers is to use 100 volts (I don't know about USA, I've read another comment about 25 volts, which seems to be the same trick on an idiot-proof voltage level). Nearly all super markets that I know use 100 V sound distribution for the background music and anouncements. The power amplifier drives the line with 100 volts at maximum output (usually using an output transformer), each speaker has a transformer that matches 100 volts to the power and impedance of the speaker. This sounds like a hifi enthusiasts nightmare, but it sounds pretty good when done right. There are several benefits: You can not kill a 100 V / 10 W speaker with a 100 V / 1000 W amplifier at full power, it will simply emit 10 W. (But a 100 V / 10 W amplifier will be killed by a 100 V / 1000 W speaker.) The high voltage makes wire resistance nearly irrelevant, you can wire 100 V sound as you would wire light bulbs. You can even use the same switches. Most speaker transformers have several inputs, allowing you to reduce the volume by switching to another input. There are also wall-mount potentiometers to adjust the volume, but they trade volume for heat. The main disadvantage is pretty obvious: You need one transformer per channel in or behind your amplifier, and one transformer per speaker. You can add the transformers to common hifi equipment, but there are also professional amplifiers with build-in transformers, usually rack mounted, and professional wall-mounted or ceiling-mounted speakers with transformers. At least the latter will kill your budget.
If your house does not have much metal inside the walls, i.e. if you can use one set of wireless speakers even through several walls, you could buy several identical sets, one set for each room. Set up all receivers (speakers) to "listen" to the same transmitter, connected to your PC. No cables (except for the speaker's power line), no impedance trouble, but depending on the quality of the sets, you may have some RF interferences (especially with a mobile phone nearby).
There are power line audio distribution systems (Devolo is very popular in Germany). You run a wire from your PC to a wall brick, that modulates your audio signal onto a HF carrier, and injects it into your power line. Other wall bricks in other rooms filter the HF carrier from your power line and demodulate the audio signal. Another wire runs from the brick to some amplified speakers. Like before, no cables, no impedance trouble. No RF interfaces, but the Develo bricks may kill your budget.
Tux2000
The best protection for any kind of application you hand over to a customer is a clear license agreement stating what is allowed and what not, together with a good lawyer. It is probably the best way to make the lawyer write the license agreement together with you.
Just as a good hint for you and your customer(s), you may digitally sign your code with a private key (using PGP or similar). Refuse any kind of support when the signature validation fails, i.e. the code is modified. Think of it as a "warranty void if seal broken" in code. Don't check the signature in the code, this is just stupid. The first step of modifying your code would be to remove the signature checker. The signature checker is a separate application on your computer(s) that you do not give away. It may be just a simple shell script using PGP and your public key.
Don't even think about encrypting your code, this is plain stupid. Your application needs to know how to decrypt the code, and the decryption engine must be unencrypted to run. So with a minimal modification of the decryption engine, your customer can read your code anyway. A binary decryption engine (XS in Perl) is not directly readable, but it makes the job just a little bit harder. There are decompilers out there.
Tux2000 <- gave away 100.000 lines of code to paying customers, multiple times
Impressive, but not really useful for daily use. I know the first 11 digits, that's more than enough if I have to use a cheap calculator without PI and trigonometric functions.
For common daily calculations, knowing 3.14 or 3.1416 (rounded!) is usually sufficient:
The german car taxes are calculated based on the volume of the engine, calculated with PI = 3.14. This (technically wrong) value is also written into the vehicle registration certificate, with three to five digits. The calculation rule origins to the the time after WW II, when most calculations were done on paper. Using only three digits of PI instead of six, eight, or ten reduced the amount of work and caused only a negligible error (less than 1%).
Tux2000