and much more "out of the box" than any open product.
Have you actually compared the software solutions available, or are you simply assuming that "open source" means "box of parts"? As a simple example, OpenOffice.org is open source - and it's as "out of the box" as software can be.
Price: Setting up a high quality FOSS POS terminal takes about $300 in POS hardware + an old computer. Turnkey COTS solutions generally cost about ten times that much.
No vendor lock-in: Any decent Linux-aware consultant can come up to speed on and support any of the major FOSS point-of-sale packages pretty quickly. Once they do, they can provide support up to and including the creation of custom features.
Ease of use: No lock-in means no annoying anti-features that could potentially prevent the administrator from getting work done. These FOSS programs generally use standard databases and standard file formats, which allows standard tools to manipulate the data. This may not apply in the same way to a non-technical user, but clearly the questioner is expecting to be able to personally take advantage of this point.
This *is* assuming that the original poster really is technically capable enough to plug in three hardware devices and set up a single piece of software. If they're not, it's probably worth hiring the consultant to begin with.
But have you *really* tried looking for a software project in SourceForge lately?
Yea. I have. And you're right, there's a lot of noise. But there's also enough signal to make it worth the time.
Here's the thing: If you want to make a good decision, you have to actually spend the time researching the topic. There's no way around it. And when the topic is availability of free software, freshmeat and sourceforge are the place to start.
Advice is great and all, but it should just be another component of your research. If everyone just relies on advice rather than looking into problems themselves, the same wrong answers and mistakes will just keep getting repeated over and over forever.
Now, my post was direct advice - based on real experience from actually implementing a POS system in a small retail environment like the one described in the question. And part of that advice - a small but key part - is to do the damn research before implementing anything.
The pieces to implement any sort of reasonable retail POS setup using FOSS are all available.
There are two things that it sounds like you're going to have problems with though:
Budget - Doing this sort of project poorly is worse than not doing it at all - you're going to want to cough up the money for a real barcode scanner and a real POS cash drawer to replace your current register.
Realistic features - This problem has already been solved, and well, but if you make up a bunch of random features beforehand (like OO.o spreadsheet output) you can be sure that none of the existing solutions will have the exact feature set that you're imagining. Unless you're prepared to write an entire system from scratch, see what exists and adapt to it.
The last time I looked into this specific problem the nicest looking piece of software for my requirements was L'âne, but you'll want to actually do the research yourself (try searching on Freshmeat and Sourceforge at minimum).
Christianity hasn't acted that way in hundreds of years.
You're talking about the religion that bombs abortion clinics, right?
Radical totalitarian Islam actually has entire countries where it has free reign. Radical totalitarian Christianity does not. That prevents Christianity from openly stoning adulterers and such. That doesn't mean that there aren't radical Christans who would do that if they could get away with it.
Christianity teaches its followers to spread their faith, but the core message contained therein is much more peaceful.
And Islam is the "religion of peace". Neither religion is purely peaceful or purely violent, and members of either religion claiming that theirs is "more peaceful" are worthy of distrust at best.
Between the Soviet Union and China, many more died for Communism than because of religious violence.
It's the same problem though - a group of people that is sure that they have the truth and that everyone else needs to be converted to their beliefs, by force if necessary.
Sure, "everyone has to follow our economic system" has been a big killer in the 20th century - but that doesn't make "everyone has to follow our spiritual beliefs" any less dangerous. In fact, religion has more *potential* for danger because at least the economic system thing is claiming its basis in rational thought so there's some hope of reasoning with it.
Well, I guess religion hasn't been the single greatest force for murder and oppression in the last century after all.
No. That force has been oppressive governments. Not terrorists (religious or not). Not even wars with other countries. The largest source of murder and oppression in the last century has been people's own national governments acting against them.
They've put quite a bit of thought into how to efficiently allocate time on a 60 million dollar compute cluster, I can assure you. If some jobs get time, it's because non-trivial progress can be made on those things in the time they've been allocated.
You're missing a source of inefficiency in the battery setup: The battery charger. Those things are damn inefficient, especially when they're being powered off a voltage other than the battery voltage.
So the question is this: Is the efficiency from battery charging + electric motor better or worse than air compression + air motor. You could easily go find numbers and prove yourself right, but assuming without the actual numbers is silly.
I think you're massively overestimating the amount of energy that humans can generate.
Here's some math:
The recommended daily energy intake for a person is around 2000 food calories. That's around 8 million joules. A Watt is a joule per second, so a humans entire daily food intake is (with perfect efficiency) is almost enough to constantly power a 100 Watt lightbulb.
The smallest engine that has been used in the Smart Fortwo is rated at 37,000 Watts. That means that the output of the engine on a tiny car is equal to the *entire energy usage* of 370 people.
In conclusion, when we accept the fact that humans probably can't use their entire energy supply to power your electricity generating bicycle, your idea is off by at least 3 orders of magnitude. Sorry.
I wouldn't just immediately assume that the efficiencies add up better for the EV. Batteries suck pretty bad, and the energy coming out of a compressed air tank is already mechanical energy in basically the form you want for moving a vehicle forward.
It's entirely possible that compressor + air tank + air motor is a more efficient path than charger + battery + electric motor.
You'd actually have to get Linux users who don't currently use Photoshop to buy it.
There's that, and then there's the Linux users who *do* currently use Photoshop and would be happy to buy the Linux version rather than having to deal with whatever complex scheme they have set up to run the Windows / Mac version.
A large percentage of Adobe's sales is existing customers buying new versions, and a Linux version would act a lot like a new version for some users.
Not enough return on investment... (at least in the near future)
That's the simple answer, and what Adobe would say to their stockholders.
The correct answer is this: It's impossible to estimate the return on investment and so they're erring on the side of not doing anything - since it's hard to blame someone for *not* taking an action that could be portrayed as risky.
When it comes to raw return on investment, a Linux port of the Adobe creative suite would probably pay for itself pretty quickly - porting is damn cheap compared to what they charge for a copy of their software.
The real issue here is one of business complexity. Corporate executives *hate* complexity because it makes it harder for them to hold all the business details in their head. They're perfectly willing to throw away a percent or two of revenue just to avoid the staff required to maintain and support something like a Linux port. It's not the cost of the staff, it's the slots on the organizational chart that allow for more risk of mismanagement.
The purpose of this document is not as a simple summary of some licenses, it's explicitly *advice* from a *team of lawyers* on the legal aspects of running a free software project. If you aren't running a free software project or don't want advice from the SFLC, then this document is not for you.
Itanic failed because the machines had horrible price/performance except in very tiny niches. One of the things that killed Itanic is x86 clusters - aka. parallel programs.
Multicore processors, in contrast, are free. What I mean by that is this: Dual core processors cost basically the same as single core processors at the same core speed. You can still buy single core processors today, but nobody does - there's no reason not to take the free second core. For a variety of reasons, the same thing will be true for quad core processors in a couple years.
By 2011 or so, everyone will have a multicore processor, every application will have multicore support, and looking back the question will seem stupid.
Itanic really was a good architecture - but nobody spent any time on it because nobody actually had the processors. Symmetric multicore x86 is quite a bit less elegant, but it'll get used extremely effectively because *everyone* will have one to play with.
Once a system has been compromised, you don't know what the attacker may have done that you don't know about.
What I said was "If an attacker gets full knowledge of your security system" not "If an attacker breaks into (and potentially modifies) your system". For the purpose of discussion of security properties, these are very different scenarios.
That's true, but it's also true (and, in my opinion, at least as relevant) that algorithms have been historically proven to be reliably impossible to keep secret.
Right. That's why the "security by obscurity" rule of thumb arose.
Here's an easy test to see if you're dealing with a "shared secret" as the term is used in the context of secure system: If every detail of your security system - including your shared secret - is discovered by an attacker, you can easily generate a new shared secret and have all the security you had before.
Cryptographic keys, passwords, and port knocking sequences are all explicitly designed to be easily changed - in fact, there's usually a set schedule for changing them. PRNG algorithms (or any other sort of algorithm) are generally not designed to be frequently and easily changed, and relying algorithms that are only secure if kept secret is the classic example of security by obscurity.
Sure, you could probably come up with edge cases if you tried really hard - but just because I can't tell you the exact decimal representation of PI doesn't mean that it might be greater than 20.
Passwords are essentially a form of security through obscurity.
The phrase "security through obscurity" has a well established meaning in the discussion of security measures. It refers specifically to systems that are only secure if the design is not known to the attacker.
Specific passwords (or other shared secrets like symmetric keys) are not part of the design. The design merely says that you use one, not which one you use - and security of the shared secret is only based on keeping which key / password is being used secret.
I've never understood why Americans seem to admire people who fight in wars so much; could you enlighten me as to why?
Consider the case where the war was obviously important - say some force was invading your country - wouldn't it be *obvious* to admire soldiers who fought in your defense? The situation in the United States is merely what you get when you take that sentiment and apply fuzzy logic to it (claiming that that Iraq war is "Defending America" for example).
Even if the federal government hiring people with tax dollars to create jobs is an efficient plan economically (and only an economist can answer that question), there are better ways to do that than the military. As an example, funding NASA as an employer would be a less destructive use of tax dollars.
[ Isolationist thinking ] while your butt is sticking in the air.
Or maybe I'm looking very carefully, and think that it might possibly be a good idea to stop punching the giant hornet's nest and get the hell out of there. Constantly interfering in the rights of other sovereign nations can only come out in two ways (world war or world government), and I want to see neither.
Maybe your job should be cut and save money?
If my job was threatening people with military force, and it was being paid for with tax dollars, I'd vote to have it cut. No-one has a right to a government job - and no-one argues that they should outside of France and maybe Italy.
Supporting big government spending with the "jobs" argument continues to be lame, especially for non-economists. I'm not an economist, but the one thing I do know is that there are better policies to create many good jobs than to pay military personnel to hang out and play golf in Japan.
The President could do quite a bit for the military budget by simply ordering the personnel home. Once they were hanging out on military bases here, it'd be really easy to argue that their positions could be safely cut (and the money saved) - and the president does have quite a bit of influence on the budget in practice.
To translate it into plain English, he thinks we should have nothing to do with a government-sponsored space-race.
He actually didn't even say that.
What he said was this: First, we need to get rid of our insane military budget. Then we can have wonderfully interesting debate on whether we should have a 25% tax cut or double NASA's budget and have a 24% tax cut.
A good standard is possible - and once a specific good standard is finalized I can see myself being for that standard. But we both know what happened the last time the federal government tried to standardize something about voting: Mandatory DREs. Given that, I'm going to have to stand by my position of being strongly against any non-specific standard.
Slashdot Mirror
Have you actually compared the software solutions available, or are you simply assuming that "open source" means "box of parts"? As a simple example, OpenOffice.org is open source - and it's as "out of the box" as software can be.
There are three counter arguments:
This *is* assuming that the original poster really is technically capable enough to plug in three hardware devices and set up a single piece of software. If they're not, it's probably worth hiring the consultant to begin with.
Yea. I have. And you're right, there's a lot of noise. But there's also enough signal to make it worth the time.
Here's the thing: If you want to make a good decision, you have to actually spend the time researching the topic. There's no way around it. And when the topic is availability of free software, freshmeat and sourceforge are the place to start.
Advice is great and all, but it should just be another component of your research. If everyone just relies on advice rather than looking into problems themselves, the same wrong answers and mistakes will just keep getting repeated over and over forever.
Now, my post was direct advice - based on real experience from actually implementing a POS system in a small retail environment like the one described in the question. And part of that advice - a small but key part - is to do the damn research before implementing anything.
The pieces to implement any sort of reasonable retail POS setup using FOSS are all available.
There are two things that it sounds like you're going to have problems with though:
The last time I looked into this specific problem the nicest looking piece of software for my requirements was L'âne, but you'll want to actually do the research yourself (try searching on Freshmeat and Sourceforge at minimum).
You're talking about the religion that bombs abortion clinics, right?
Radical totalitarian Islam actually has entire countries where it has free reign. Radical totalitarian Christianity does not. That prevents Christianity from openly stoning adulterers and such. That doesn't mean that there aren't radical Christans who would do that if they could get away with it.
And Islam is the "religion of peace". Neither religion is purely peaceful or purely violent, and members of either religion claiming that theirs is "more peaceful" are worthy of distrust at best.
It's the same problem though - a group of people that is sure that they have the truth and that everyone else needs to be converted to their beliefs, by force if necessary.
Sure, "everyone has to follow our economic system" has been a big killer in the 20th century - but that doesn't make "everyone has to follow our spiritual beliefs" any less dangerous. In fact, religion has more *potential* for danger because at least the economic system thing is claiming its basis in rational thought so there's some hope of reasoning with it.
No. That force has been oppressive governments. Not terrorists (religious or not). Not even wars with other countries. The largest source of murder and oppression in the last century has been people's own national governments acting against them.
They've put quite a bit of thought into how to efficiently allocate time on a 60 million dollar compute cluster, I can assure you. If some jobs get time, it's because non-trivial progress can be made on those things in the time they've been allocated.
The GPL allows competition.
Microsoft's entire business model is to exploit the monopolies granted by copyright and patent law.
You're missing a source of inefficiency in the battery setup: The battery charger. Those things are damn inefficient, especially when they're being powered off a voltage other than the battery voltage.
So the question is this: Is the efficiency from battery charging + electric motor better or worse than air compression + air motor. You could easily go find numbers and prove yourself right, but assuming without the actual numbers is silly.
Excellent plan. Just don't ever hold two paperclips of the wrong length in opposing hands in that room or you *die*.
I think you're massively overestimating the amount of energy that humans can generate.
Here's some math:
The recommended daily energy intake for a person is around 2000 food calories. That's around 8 million joules. A Watt is a joule per second, so a humans entire daily food intake is (with perfect efficiency) is almost enough to constantly power a 100 Watt lightbulb.
The smallest engine that has been used in the Smart Fortwo is rated at 37,000 Watts. That means that the output of the engine on a tiny car is equal to the *entire energy usage* of 370 people.
In conclusion, when we accept the fact that humans probably can't use their entire energy supply to power your electricity generating bicycle, your idea is off by at least 3 orders of magnitude. Sorry.
I wouldn't just immediately assume that the efficiencies add up better for the EV. Batteries suck pretty bad, and the energy coming out of a compressed air tank is already mechanical energy in basically the form you want for moving a vehicle forward.
It's entirely possible that compressor + air tank + air motor is a more efficient path than charger + battery + electric motor.
There's that, and then there's the Linux users who *do* currently use Photoshop and would be happy to buy the Linux version rather than having to deal with whatever complex scheme they have set up to run the Windows / Mac version.
A large percentage of Adobe's sales is existing customers buying new versions, and a Linux version would act a lot like a new version for some users.
That's the simple answer, and what Adobe would say to their stockholders.
The correct answer is this: It's impossible to estimate the return on investment and so they're erring on the side of not doing anything - since it's hard to blame someone for *not* taking an action that could be portrayed as risky.
When it comes to raw return on investment, a Linux port of the Adobe creative suite would probably pay for itself pretty quickly - porting is damn cheap compared to what they charge for a copy of their software.
The real issue here is one of business complexity. Corporate executives *hate* complexity because it makes it harder for them to hold all the business details in their head. They're perfectly willing to throw away a percent or two of revenue just to avoid the staff required to maintain and support something like a Linux port. It's not the cost of the staff, it's the slots on the organizational chart that allow for more risk of mismanagement.
The purpose of this document is not as a simple summary of some licenses, it's explicitly *advice* from a *team of lawyers* on the legal aspects of running a free software project. If you aren't running a free software project or don't want advice from the SFLC, then this document is not for you.
Itanic failed because the machines had horrible price/performance except in very tiny niches. One of the things that killed Itanic is x86 clusters - aka. parallel programs.
Multicore processors, in contrast, are free. What I mean by that is this: Dual core processors cost basically the same as single core processors at the same core speed. You can still buy single core processors today, but nobody does - there's no reason not to take the free second core. For a variety of reasons, the same thing will be true for quad core processors in a couple years.
By 2011 or so, everyone will have a multicore processor, every application will have multicore support, and looking back the question will seem stupid.
Itanic really was a good architecture - but nobody spent any time on it because nobody actually had the processors. Symmetric multicore x86 is quite a bit less elegant, but it'll get used extremely effectively because *everyone* will have one to play with.
What I said was "If an attacker gets full knowledge of your security system" not "If an attacker breaks into (and potentially modifies) your system". For the purpose of discussion of security properties, these are very different scenarios.
Right. That's why the "security by obscurity" rule of thumb arose.
Here's an easy test to see if you're dealing with a "shared secret" as the term is used in the context of secure system: If every detail of your security system - including your shared secret - is discovered by an attacker, you can easily generate a new shared secret and have all the security you had before.
Cryptographic keys, passwords, and port knocking sequences are all explicitly designed to be easily changed - in fact, there's usually a set schedule for changing them. PRNG algorithms (or any other sort of algorithm) are generally not designed to be frequently and easily changed, and relying algorithms that are only secure if kept secret is the classic example of security by obscurity.
Sure, you could probably come up with edge cases if you tried really hard - but just because I can't tell you the exact decimal representation of PI doesn't mean that it might be greater than 20.
The phrase "security through obscurity" has a well established meaning in the discussion of security measures. It refers specifically to systems that are only secure if the design is not known to the attacker.
Specific passwords (or other shared secrets like symmetric keys) are not part of the design. The design merely says that you use one, not which one you use - and security of the shared secret is only based on keeping which key / password is being used secret.
Consider the case where the war was obviously important - say some force was invading your country - wouldn't it be *obvious* to admire soldiers who fought in your defense? The situation in the United States is merely what you get when you take that sentiment and apply fuzzy logic to it (claiming that that Iraq war is "Defending America" for example).
Even if the federal government hiring people with tax dollars to create jobs is an efficient plan economically (and only an economist can answer that question), there are better ways to do that than the military. As an example, funding NASA as an employer would be a less destructive use of tax dollars.
Or maybe I'm looking very carefully, and think that it might possibly be a good idea to stop punching the giant hornet's nest and get the hell out of there. Constantly interfering in the rights of other sovereign nations can only come out in two ways (world war or world government), and I want to see neither.
If my job was threatening people with military force, and it was being paid for with tax dollars, I'd vote to have it cut. No-one has a right to a government job - and no-one argues that they should outside of France and maybe Italy.
Supporting big government spending with the "jobs" argument continues to be lame, especially for non-economists. I'm not an economist, but the one thing I do know is that there are better policies to create many good jobs than to pay military personnel to hang out and play golf in Japan.
The President could do quite a bit for the military budget by simply ordering the personnel home. Once they were hanging out on military bases here, it'd be really easy to argue that their positions could be safely cut (and the money saved) - and the president does have quite a bit of influence on the budget in practice.
He actually didn't even say that.
What he said was this: First, we need to get rid of our insane military budget. Then we can have wonderfully interesting debate on whether we should have a 25% tax cut or double NASA's budget and have a 24% tax cut.
A good standard is possible - and once a specific good standard is finalized I can see myself being for that standard. But we both know what happened the last time the federal government tried to standardize something about voting: Mandatory DREs. Given that, I'm going to have to stand by my position of being strongly against any non-specific standard.
Centralizing important things is a bad idea.
Having the federal government do it wrong for everyone is much worse than having some local communities doing it wrong for themselves.