DNS Poisoning is possible because of the way some DNS servers work.
When you want to lookup a site, you send a request to your DNS server, which then does the lookup and returns the results to you.
Say you need to know the address to www.yahoo.com. You ask the DNS server for it. It doesn't know, so it looks at what it does know. In the simplest case, it knows the address of the DNS server for *.com, so it asks him. He replies that he doesn't know either, but that he knows *.yahoo.com's DNS records are stored at x.x.x.x. So your DNS server goes and asks x.x.x.x. He does know where www.yahoo.com is, tells your DNS server, who then sends you back the address.
Typically, a DNS Server is running for a lot of users at once, so it improves speed by caching the results of these queries. So if you asked for www.yahoo.com again, your DNS server looks in the cache, finds that www.yahoo.com is in there, and gives you the answer right away. No need to look it up, time saved all around.
DNS Cache Poisoning is where an attacker tricks a DNS Server into caching incorrect information. This can happen by having a rogue server setup somewhere. So say the nameserver for www.badguy.com has records that say his name is also www.yahoo.com. When you lookup www.badguy.com, and get to that point, badguy.com says "hey, this is my address, and here's some other names that I'm known by: www.yahoo.com". Your DNS Server then stores all that info in his cache. Later you lookup www.yahoo.com and get back the address for www.badguy.com instead.
That's a slightly oversimplified way to explain it, but that's the gist of it. Somebody can trick your DNS server into giving back bad info. This is a critical security issue, because say they poison your cache and fool you into connecting to their server instead of, say, your bank's. They then give you a web page that looks just like your bank's does, you login as normal, and suddenly they have all your cash.
Many DNS servers are immune to this. How is simple: They don't cache stuff when badguy.com says he's also yahoo.com. They always go ask who yahoo.com is and only cache that more trustworthy answer.
However, the DNS system is setup as a hierarchy. Your DNS Server may not talk to root servers all the time, he might route all his queries through another, bigger DNS server. One of the bugs discovered here is that even if your DNS server is not vulnerable, the one just upstream of it might be, and that can propagate down to yours.
I also have a V3, and its USB power can only be used to "top off" an already existing charge. if you ever get the phone to a dead state, a USB port is useless. The usb charging doesnt begin until the software in the phone requests power from the port.
The problem here is that an actual computer needs to be told to provide power to the device by the device itself. A totally dead device clearly cannot do that. However, anything above totally dead, including when it is "off" has enough juice to talk to the computer and tell it to ramp up the power output to charge. Even a trickle of charge would be enough. It does work.
another problem, is that to charge a dead phone you need a motorola(TM) razr(TM) usb charger, which arent very redily available yet. You mean other than the AC adapter that comes with your phone?
The miniUSB port on the thing is the *only* connection the Razr has. The AC adapter just provides power to that connection regardless of WTF the phone asks for. It's just a simple transformer.
And for charging it from a computer, any standard USB->miniUSB cable works.
another problem is that a USB port cant provide enough juice to both charge the phone, and make a call. if you talk on USB power, your phone will eventually go into a totally dead state (see above for how fun that is).
Most cell phones are like this. They don't charge while talking. I've never seen one that isn't like this, in fact. Generally it's because they use more power to communicate than the power port provides, even when you have a dedicated power port. The use of USB power connectors isn't the problem there.
yet another problem, is that file transfer over USB isnt possible (it might be with additional software). I can exchange ringtones and pictures only via bluetooth, and can sync a phone book only with USB. totally wierd.
File transfer is possible over the wired connection. More so than over the bluetooth, in fact, as you need the wired connection to be able to flash the phone with new software and such. Check out motorola.howardforums.com for more info.
And the phone book sync works fine over USB. You can send/receive VCF files using the OBEX object transfer without any extra software other than the bluetooth stack, and do complete syncs if you have the right software to deal with it.
Pretty much, yeah. Of course, they wouldn't patent turning chunks of "000000000" into "01"'s, they'd patent "turning sets of numbers into other numbers by a predictable algorithim using intrinsic compression methods". Then they'd also be covered if you decided to turn it into "02" or something.:)
In general, you're right, however this is a specific case of opting-into a mailing list of whatever kind. Having a mailing list without having confirmed opt-in is almost the definition of a spammer.
No, I don't think they had anything like that. I don't think the idea ever really occured to them.
The point he's making is that your post was wrong in the first place. As you posted:
I used to work for a company that send a plain text newsletter to a 100% opt-in mailing list once a month.
Your initial post is self-contradictory. If you had a 100% opt-in system, then nobody on the list would have been able to be signed up without them confirming it. That's what "opt-in" means. Just having a web page with a textbox to stick an email address into is not "opt-in", because, as you yourself discovered, somebody else can sign up other people to your list. You have to confirm email addresses before actually spamming them in order to be able to call yourself "100% opt-in".
Yay, you win, you have a program that is messing up your security center settings.
Now take the 15 seconds to disable the service.
Wow, that was tough.
Uh huh. The point being that the WSC loses its settings under some circumstances. I don't have a program that goes and erases the settings, it's a bug in the WSC itself, somehow, somewhere.
Some user that knows shit about services would have a fairly frustrating time of it, having to reset the damned thing every time they reboot or log in.
You sure? Cool air in the *top*? All the ones I've seen (and all the rack equipment manufacturers accessories) pull cool air from under the raised floor and pull it *up* through the rack. This is because the hot air your systems are exhausting is already rising, and pulling the cool air up and exhausting at the top makes a lot more sense!
You might be right, but I know what I saw and it worked incredibly well.
Sucking the hot air out the top would certainly work, but feeding cool air into the bottom is not a particularly easy thing to do for most racks. You'd basically need to cool the whole room then, and that seems cost less effective than cooling the racks only.
As for "can't be proven/disproven", you're the one who's full of crap. It's easily "proven". Come over to my place, I'll turn the security center back on, disable those alerts, reboot, and you can bloody well watch it continue to alert me.
If you mean that you can't "prove" it by sitting on your ass and spouting off shit you know absolutely nothing about, then yeah, you have a point.
Yeah, I know, clicking 'do not monitor firewall' was real tough, took 6 clicks total.
And then turned itself back on after a reboot. There is/was some kind of bug there where it can lose/ignore those settings and default back to trying to monitor everything in some circumstances.
Of course, given that people ignore popups, what's that worth?
Ignore it or click cancel or whatever, and it pops back up every 10 minutes or so. Disabling it can be done, but that's actually more difficult than enabling the firewall.
I don't use the software firewall on my XP box (hardware firewall is enough for me) and getting it to disable checking for the software firewall status and actually have that *stay* disabled was a bit of an exercise in patience.:)
Exactly. OSDL and BitMoover had an agreement, and OSDL violated it. That makes OSDL the "bad guys".
No, it makes BitMover the bad guys for including that in the agreement in the first place.
Even if you think they didn't violate the letter of the contract, they definitely violated the spirit of it. IMHO, that's just as bad, if not worse.
See, I say just the opposite. They might have violated the letter of the agreement, but there's no way they violated the spirit of it. I cannot see them agreeing in spirit to something which essentially says "you'll fire employees for what they do in their spare time if we tell you to".
Of the many server rooms I've been in, the most effective cooling I've seen has been to enclose the racks into sealed cabinets (adding a cheapish layer of physical security as well, by locking the things) and then piping cooled air directly into the top of the cabinets.
If you buy your own racks to put gear in, then getting these things is easy, if you buy whole racks from a vendor with gear in it already (custom systems type of thing), then the thing comes in a cabinet which usually has some kind of a fan/vent arrangement on top. Rip that off, attach some ducting straight up to the ducts running across the rows, and voila, cool air flows straight down and out the bottom.
All you need is to build your room with several ducts running across the ceiling, with removable plates every so often. The AC system pushes air into that, which then goes directly into the racks. You don't even need to cool the room really, since the air coming out of the racks gets cool enough to keep the room itself cool. The servers in the racks stay at fairly chilly temp in there. Only downside is when you need to open one, you're hit in the face with this freezing air pouring out of the rack.:)
I only steal on my own free time. They can't fire me for that.
What, exactly, was stolen here? Not BitKeeper, it was freely available.
Either this guy did one of two things:
-Reverse engineered it to make his own product interoperable with it, which is not only 100% legal but a very useful thing to do from BitMover's perspective. More software that works with their stuff means more people buying their stuff to use with this software.
-Wrote his own software with features similar to those in BitKeeper, which can in no possible way be considered "stealing". Considering that most of those features were probably the ones more useful for the OSS community, and that most of those features in BitKeeper were suggested by the OSS community (as Larry himself says in TFA), then they're not even BitMover's original feature ideas in the first place.
No, this is a gut reaction by BitMover and Larry. They're not thinking it through all the way because they don't have the open source mindset. They were using Linus and the popularity factor to promote their product, they think that they've milked that cash cow for all they can, and now they use an excuse to end that support because it's not as profitable for them to keep up the pretense anymore. Simple decision there.
Bitmover is not an open source company and they don't understand open source principles. All the rest is just side issues.
If you cannot reap the fruits of your innovation, why bother to innovate? Where's the stimulus? Yeah, because everybody knows we wouldn't have the internet without proprietary software IP. Oh, wait, the internet was built on open sourced protocols and open sourced software. Okay, bad example.
Why is it when someone says something that is true, it is an "attack"? Because they say it as if it's a bad thing. The "bad" part of it makes it an "attack".
It's just that the response to this particular attack is "Well, of course it's true! That's the whole point! It's not a bad thing, it's the intended design of the thing! We like it that way!" and so on...
Personally, I don't think that the engineers in developing nations are so stupid that they fail to recognize this fact and need our help to remind them. I do think, however, that many engineering companies management teams will seriously pause at the idea of giving up their research under the GPL, for the same reasons as any management team which sees a value in proprietary knowledge.
While this is no doubt true, they have a simple remedy to this: Don't use software under the GPL. Easy. What I really don't understand is anybody thinking that they are free to use this software made by other people and extend it into their systems and projects, without doing the same in return by giving back to those they got the software from.
Yes, yes, greed, I get it, but in that case this sort of argument that Schwartz is making is still wrong, because he's basically saying that preventing people from being greedy is a bad thing, that greed is somehow good. When it should be pretty obvious that greed, in general, is bad. Now, I'm not arguing against capitalism here, but at the same time there's plenty of precedent to backup "greed is bad" overall.
While this proprietary knowledge has a value from their standpoint, it's a simple matter of balance. They are receiving the GPL software freely. That software has value as well. If they are going to develop using it, they must give value back in return. TANSTAAFL.
Otherwise, they can not use the GPLd stuff and develop their own software all the way around. If they think their software will have more value than the GPL software they start from, then they shouldn't use GPL software.
BitMover is in the right (but only legally)
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No More BitKeeper Linux
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OSDL had an agreement with BitMoover, and therefore the contractors they hire must also abide with that agreement.
Which is, of course, the biggest line of bullshit ever. A company does not own its employees. While BitMover is legally in the clear here (the contract is the contract), they're morally in the wrong to have included such a line in the first place.
It's one thing to tell companies you're giving free stuff to "hey, don't develop a competing product". That's cool. But OSDL wasn't developing a competing product. Some guy who worked for them was developing stuff on his own time and OSDL didn't fire him for it. BitMover's agreement basically says "not only can't you develop a competing product, but if you pay anybody who does or offer them any assistance or do anything other than kick the hell out of them, we're through".
Making other companies into your goon squad to prevent competing products from appearing just because you're giving them some free software isn't morally sound. Competition is good, unless you're the one being competed against, right? Expecting that relationship to actually last, especially in a world where people think software should not only be free as in beer but also free as in speech, was perhaps a bit foolish on all sides, but in no way can you make BitMover out to be the good guy here.
Larry is being a jackass, he probably knows it, and he probably doesn't much care.
Does it allow you to convert selected session cookies into persistant cookies as well?
No, however I can think of very, very few reasons to do that. A session cookie is generally used to hold data for only short amounts of time, usually an ID that the website uses to look something up in a database or what have you. There's no case I can think of where you would want a session cookie to persist, off the top of my head.
Anyway, it'll let you protect a session cookie, but FF will still kill them when you close the browser. CookieCuller's protection only applies to CookieCuller.
Personally, I think time runs backwards inside the event horizon, as the ever-increasing energy density (from an outsider's point of view) is anentropic, and time always flows in the entropic direction. But I can't back that up.:)
Actually, if you buy Einstein's Field Equations and more specifically solution that defines the Schwarzschild metric, then it tells you that for regions close to a mass with distance that is smaller than the Schwarzschild radius, some damned odd things occur. Considered in radial coordinates, r (the radius) and t (time) swap places. r becomes timelike and t becomes spacelike. To the effect that r can no longer be held constant over any given period of increasing time. In other words, even holding your position becomes impossible. Going forward in time means going towards the singularity.
As I understand it, for a trillion-solar-mass black hole, gravitational acceleration at the event horizon is only about 1G.
Don't know where you got that idea. If you assume a simple non-rotating black hole, then the Schwarzschild radius (aka the event horizon) is the distance from the singularity at which the gravitational field is so powerful that the black hole's escape velocity is greater than the speed of light. r = 2GM/c^2, where r is the Schwarzschild radius - the distance from the singularity to the event horizon. You can even get this from the Newtonian escape velocity equation, just set v = c and solve for r.
Now, plug that radius into the standard acceleration formula: a = GM / r^2. Result: a = c^4 / 4GM. a = acceleration due to gravity at the event horizon, M = mass of black hole.
So about 1551 G's. If you add more mass, the acceleration drops off, of course.
It's not that you can't accellerate hard enough to overcome gravity, but the effects of a massive object on space itself that makes a black hole inescapable.
Yes, I see your point now. Say you're in a spaceship just inside the event horizon of that trillion sun hole above, and decide to gun the engine to 2000 G's to get the hell out. Why can't you? And the answer is that it's because of a the way space is curved inside the event horizon, so yeah, Newtonian mechanics can't cover this situation. Light can't change its speed, only it's direction. You can change either one, but are still screwed for different reasons.
There's a Firefox plugin called CookieCuller that I find very convienent. Basically, it deletes all your cookies when you close the browser (or perhaps when you start it up.. either way). It will also allow you to see the current cookies easily and to set individual ones as "protected", meaning it won't touch these.
It's extremely useful, as it will allow you to keep some persistent cookies (like your slashdot login, for example) while auto-killing the rest of them. All you have to do is login to a site, open the CookieCuller window, then find that site and tell it to protect that site's cookies. Voila. Very easy and handy.
An object does not have to reach escape velocity to escape a planet's gravitational pull.
You're partly right. You can NEVER escape a planet's gravitational pull. It just keeps pulling, no matter how far you go.;)
Escape velocity is the inital speed needed for a ballistic object to ensure that the gravitational pull of the planet will never be able to bring it to a complete stop, relative to the planet. As you move away from the planet, the gravitational force weakens. If you can move away faster than the force can slow you down, then the gravity of the planet can never stop you. That's the escape velocity.
However, for a rocket (or other powered device) to escape a planet's gravitational pull, as the GP said, all it has to do is provide enough vertical thrust to provide a positive acceleration. That acceleration does not have to accelerate it to the escape velocity - in fact, you could adjust it to compensate for the falling gravitational pull and so maintain a constant velocity of whatever you want, and (if you have sufficient power/fuel) you'll still escape.
In theory, you're partly correct here. If you could overcome gravity to provide a 1 foot per second squared upward accelleration, then yeah, you'd get to outer space. Eventually. It'd take one hell of a lot of fuel though, because you're only barely overcoming gravity. It's not actually *possible* because no ship exists that can do that and also have enough fuel to do it.
Any acceleration larger than gravity will get you there eventually if you assume enough fuel. And as gravity drops off due to distance, eventually you'll be travelling faster than escape velocity for the given height you happen to be at. And then you're free.
That doesn't work for a black hole because all of that is based on Newtonian mechanics, which do not apply in the large gravitational fields close to the event horizon. There, you must use General Relativity, which is counter to our everyday common sense view of the world (precisely because on our scales, it's irrelevant). I don't know enough about GR to demonstrate why this is, however.
The main reason is similar to the above: You don't have enough fuel. And not just because the technology doesn't exist, but because inside the event horizon, the acceleration due to gravity is so high that even light itself isn't moving fast enough to go "up". No amount of acceleration will let you make any forward progress at all, because you cannot possibly give it enough speed to exceed the speed of light. So you can't even go up at 1 foot per second, you can only go down.
To put it another way, inside the event horizon, space is bent in such a way that moving away from the singularity is no longer an available option.
Outside the event horizon, the normal, simple, equations still apply, more or less. The gravity is high, but the concept is the same. With a higher gravity comes a higher escape velocity, that's all. Also time dilation, but that's rather irrelevent to this discussion.;)
Also google for "Oxford Electric Bell". This particular type of battery has been ringing a bell (albeit inaudibly) in the foyer of a lab in Oxford for over 160 years.
The gist of it is that you get small circles of zinc foil, silver foil, and paper. Then you stack 'em up (silver, zinc, paper, repeat). Next you stick the whole thing in a glass tube and compress it. You want several thousand of them, basically. Once you're done, coat the whole thing in plastic to prevent oxidation from eating it away.
What you end up with is a battery that will power something reasonably small for a long, long, long time. Certainly could power a simplistic clock for a thousand years. Once your clock goes off, you make some sort of signal. Audio perhaps, since that's probably more reliable than radio would be over that time period.
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DNS Poisoning is possible because of the way some DNS servers work.
When you want to lookup a site, you send a request to your DNS server, which then does the lookup and returns the results to you.
Say you need to know the address to www.yahoo.com. You ask the DNS server for it. It doesn't know, so it looks at what it does know. In the simplest case, it knows the address of the DNS server for *.com, so it asks him. He replies that he doesn't know either, but that he knows *.yahoo.com's DNS records are stored at x.x.x.x. So your DNS server goes and asks x.x.x.x. He does know where www.yahoo.com is, tells your DNS server, who then sends you back the address.
Typically, a DNS Server is running for a lot of users at once, so it improves speed by caching the results of these queries. So if you asked for www.yahoo.com again, your DNS server looks in the cache, finds that www.yahoo.com is in there, and gives you the answer right away. No need to look it up, time saved all around.
DNS Cache Poisoning is where an attacker tricks a DNS Server into caching incorrect information. This can happen by having a rogue server setup somewhere. So say the nameserver for www.badguy.com has records that say his name is also www.yahoo.com. When you lookup www.badguy.com, and get to that point, badguy.com says "hey, this is my address, and here's some other names that I'm known by: www.yahoo.com". Your DNS Server then stores all that info in his cache. Later you lookup www.yahoo.com and get back the address for www.badguy.com instead.
That's a slightly oversimplified way to explain it, but that's the gist of it. Somebody can trick your DNS server into giving back bad info. This is a critical security issue, because say they poison your cache and fool you into connecting to their server instead of, say, your bank's. They then give you a web page that looks just like your bank's does, you login as normal, and suddenly they have all your cash.
Many DNS servers are immune to this. How is simple: They don't cache stuff when badguy.com says he's also yahoo.com. They always go ask who yahoo.com is and only cache that more trustworthy answer.
However, the DNS system is setup as a hierarchy. Your DNS Server may not talk to root servers all the time, he might route all his queries through another, bigger DNS server. One of the bugs discovered here is that even if your DNS server is not vulnerable, the one just upstream of it might be, and that can propagate down to yours.
So there you go.
I also have a V3, and its USB power can only be used to "top off" an already existing charge. if you ever get the phone to a dead state, a USB port is useless. The usb charging doesnt begin until the software in the phone requests power from the port.
The problem here is that an actual computer needs to be told to provide power to the device by the device itself. A totally dead device clearly cannot do that. However, anything above totally dead, including when it is "off" has enough juice to talk to the computer and tell it to ramp up the power output to charge. Even a trickle of charge would be enough. It does work.
another problem, is that to charge a dead phone you need a motorola(TM) razr(TM) usb charger, which arent very redily available yet.
You mean other than the AC adapter that comes with your phone?
The miniUSB port on the thing is the *only* connection the Razr has. The AC adapter just provides power to that connection regardless of WTF the phone asks for. It's just a simple transformer.
And for charging it from a computer, any standard USB->miniUSB cable works.
another problem is that a USB port cant provide enough juice to both charge the phone, and make a call. if you talk on USB power, your phone will eventually go into a totally dead state (see above for how fun that is).
Most cell phones are like this. They don't charge while talking. I've never seen one that isn't like this, in fact. Generally it's because they use more power to communicate than the power port provides, even when you have a dedicated power port. The use of USB power connectors isn't the problem there.
yet another problem, is that file transfer over USB isnt possible (it might be with additional software). I can exchange ringtones and pictures only via bluetooth, and can sync a phone book only with USB. totally wierd.
File transfer is possible over the wired connection. More so than over the bluetooth, in fact, as you need the wired connection to be able to flash the phone with new software and such. Check out motorola.howardforums.com for more info.
And the phone book sync works fine over USB. You can send/receive VCF files using the OBEX object transfer without any extra software other than the bluetooth stack, and do complete syncs if you have the right software to deal with it.
does that mean i can't use that kind of code?
:)
Pretty much, yeah. Of course, they wouldn't patent turning chunks of "000000000" into "01"'s, they'd patent "turning sets of numbers into other numbers by a predictable algorithim using intrinsic compression methods". Then they'd also be covered if you decided to turn it into "02" or something.
And now you see why software patents are bad.
Confirmed opt-in is not the universal solution.
In general, you're right, however this is a specific case of opting-into a mailing list of whatever kind. Having a mailing list without having confirmed opt-in is almost the definition of a spammer.
The point he's making is that your post was wrong in the first place. As you posted:
Your initial post is self-contradictory. If you had a 100% opt-in system, then nobody on the list would have been able to be signed up without them confirming it. That's what "opt-in" means. Just having a web page with a textbox to stick an email address into is not "opt-in", because, as you yourself discovered, somebody else can sign up other people to your list. You have to confirm email addresses before actually spamming them in order to be able to call yourself "100% opt-in".
Yay, you win, you have a program that is messing up your security center settings.
Now take the 15 seconds to disable the service.
Wow, that was tough.
Uh huh. The point being that the WSC loses its settings under some circumstances. I don't have a program that goes and erases the settings, it's a bug in the WSC itself, somehow, somewhere.
Some user that knows shit about services would have a fairly frustrating time of it, having to reset the damned thing every time they reboot or log in.
You sure? Cool air in the *top*? All the ones I've seen (and all the rack equipment manufacturers accessories) pull cool air from under the raised floor and pull it *up* through the rack. This is because the hot air your systems are exhausting is already rising, and pulling the cool air up and exhausting at the top makes a lot more sense!
You might be right, but I know what I saw and it worked incredibly well.
Sucking the hot air out the top would certainly work, but feeding cool air into the bottom is not a particularly easy thing to do for most racks. You'd basically need to cool the whole room then, and that seems cost less effective than cooling the racks only.
Can't find a KB article, but then MS's KB search is fairly annoying. So how about user reports instead?
t ml?p=231678
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http://extremetechsupport.org/forum/showthread.ph
http://www.codecomments.com/archive299-2005-2-409
As for "can't be proven/disproven", you're the one who's full of crap. It's easily "proven". Come over to my place, I'll turn the security center back on, disable those alerts, reboot, and you can bloody well watch it continue to alert me.
If you mean that you can't "prove" it by sitting on your ass and spouting off shit you know absolutely nothing about, then yeah, you have a point.
Yeah, I know, clicking 'do not monitor firewall' was real tough, took 6 clicks total.
And then turned itself back on after a reboot. There is/was some kind of bug there where it can lose/ignore those settings and default back to trying to monitor everything in some circumstances.
Of course, given that people ignore popups, what's that worth?
:)
Ignore it or click cancel or whatever, and it pops back up every 10 minutes or so. Disabling it can be done, but that's actually more difficult than enabling the firewall.
I don't use the software firewall on my XP box (hardware firewall is enough for me) and getting it to disable checking for the software firewall status and actually have that *stay* disabled was a bit of an exercise in patience.
I never said they were wrong legally. I said the exact opposite, in point of fact.
;-)
If you want to break it down to absolute basics, I was saying that Larry McVoy is basically an asshole.
Exactly. OSDL and BitMoover had an agreement, and OSDL violated it. That makes OSDL the "bad guys".
No, it makes BitMover the bad guys for including that in the agreement in the first place.
Even if you think they didn't violate the letter of the contract, they definitely violated the spirit of it. IMHO, that's just as bad, if not worse.
See, I say just the opposite. They might have violated the letter of the agreement, but there's no way they violated the spirit of it. I cannot see them agreeing in spirit to something which essentially says "you'll fire employees for what they do in their spare time if we tell you to".
Of the many server rooms I've been in, the most effective cooling I've seen has been to enclose the racks into sealed cabinets (adding a cheapish layer of physical security as well, by locking the things) and then piping cooled air directly into the top of the cabinets.
:)
If you buy your own racks to put gear in, then getting these things is easy, if you buy whole racks from a vendor with gear in it already (custom systems type of thing), then the thing comes in a cabinet which usually has some kind of a fan/vent arrangement on top. Rip that off, attach some ducting straight up to the ducts running across the rows, and voila, cool air flows straight down and out the bottom.
All you need is to build your room with several ducts running across the ceiling, with removable plates every so often. The AC system pushes air into that, which then goes directly into the racks. You don't even need to cool the room really, since the air coming out of the racks gets cool enough to keep the room itself cool. The servers in the racks stay at fairly chilly temp in there. Only downside is when you need to open one, you're hit in the face with this freezing air pouring out of the rack.
I only steal on my own free time. They can't fire me for that.
What, exactly, was stolen here? Not BitKeeper, it was freely available.
Either this guy did one of two things:
-Reverse engineered it to make his own product interoperable with it, which is not only 100% legal but a very useful thing to do from BitMover's perspective. More software that works with their stuff means more people buying their stuff to use with this software.
-Wrote his own software with features similar to those in BitKeeper, which can in no possible way be considered "stealing". Considering that most of those features were probably the ones more useful for the OSS community, and that most of those features in BitKeeper were suggested by the OSS community (as Larry himself says in TFA), then they're not even BitMover's original feature ideas in the first place.
No, this is a gut reaction by BitMover and Larry. They're not thinking it through all the way because they don't have the open source mindset. They were using Linus and the popularity factor to promote their product, they think that they've milked that cash cow for all they can, and now they use an excuse to end that support because it's not as profitable for them to keep up the pretense anymore. Simple decision there.
Bitmover is not an open source company and they don't understand open source principles. All the rest is just side issues.
If you cannot reap the fruits of your innovation, why bother to innovate? Where's the stimulus?
Yeah, because everybody knows we wouldn't have the internet without proprietary software IP. Oh, wait, the internet was built on open sourced protocols and open sourced software. Okay, bad example.
Why is it when someone says something that is true, it is an "attack"?
Because they say it as if it's a bad thing. The "bad" part of it makes it an "attack".
It's just that the response to this particular attack is "Well, of course it's true! That's the whole point! It's not a bad thing, it's the intended design of the thing! We like it that way!" and so on...
Personally, I don't think that the engineers in developing nations are so stupid that they fail to recognize this fact and need our help to remind them. I do think, however, that many engineering companies management teams will seriously pause at the idea of giving up their research under the GPL, for the same reasons as any management team which sees a value in proprietary knowledge.
While this is no doubt true, they have a simple remedy to this: Don't use software under the GPL. Easy. What I really don't understand is anybody thinking that they are free to use this software made by other people and extend it into their systems and projects, without doing the same in return by giving back to those they got the software from.
Yes, yes, greed, I get it, but in that case this sort of argument that Schwartz is making is still wrong, because he's basically saying that preventing people from being greedy is a bad thing, that greed is somehow good. When it should be pretty obvious that greed, in general, is bad. Now, I'm not arguing against capitalism here, but at the same time there's plenty of precedent to backup "greed is bad" overall.
While this proprietary knowledge has a value from their standpoint, it's a simple matter of balance. They are receiving the GPL software freely. That software has value as well. If they are going to develop using it, they must give value back in return. TANSTAAFL.
Otherwise, they can not use the GPLd stuff and develop their own software all the way around. If they think their software will have more value than the GPL software they start from, then they shouldn't use GPL software.
OSDL had an agreement with BitMoover, and therefore the contractors they hire must also abide with that agreement.
Which is, of course, the biggest line of bullshit ever. A company does not own its employees. While BitMover is legally in the clear here (the contract is the contract), they're morally in the wrong to have included such a line in the first place.
It's one thing to tell companies you're giving free stuff to "hey, don't develop a competing product". That's cool. But OSDL wasn't developing a competing product. Some guy who worked for them was developing stuff on his own time and OSDL didn't fire him for it. BitMover's agreement basically says "not only can't you develop a competing product, but if you pay anybody who does or offer them any assistance or do anything other than kick the hell out of them, we're through".
Making other companies into your goon squad to prevent competing products from appearing just because you're giving them some free software isn't morally sound. Competition is good, unless you're the one being competed against, right?
Expecting that relationship to actually last, especially in a world where people think software should not only be free as in beer but also free as in speech, was perhaps a bit foolish on all sides, but in no way can you make BitMover out to be the good guy here.
Larry is being a jackass, he probably knows it, and he probably doesn't much care.
Does it allow you to convert selected session cookies into persistant cookies as well?
No, however I can think of very, very few reasons to do that. A session cookie is generally used to hold data for only short amounts of time, usually an ID that the website uses to look something up in a database or what have you. There's no case I can think of where you would want a session cookie to persist, off the top of my head.
Anyway, it'll let you protect a session cookie, but FF will still kill them when you close the browser. CookieCuller's protection only applies to CookieCuller.
Everything you just listed can be done through Firefox's normal cookie management system (tools-> options-> privacy-> cookies).
True, however, CookieCuller makes it easier and simpler to do. The existing cookie management in FF is hard to use in this particular manner.
Personally, I think time runs backwards inside the event horizon, as the ever-increasing energy density (from an outsider's point of view) is anentropic, and time always flows in the entropic direction. But I can't back that up. :)
Actually, if you buy Einstein's Field Equations and more specifically solution that defines the Schwarzschild metric, then it tells you that for regions close to a mass with distance that is smaller than the Schwarzschild radius, some damned odd things occur. Considered in radial coordinates, r (the radius) and t (time) swap places. r becomes timelike and t becomes spacelike. To the effect that r can no longer be held constant over any given period of increasing time. In other words, even holding your position becomes impossible. Going forward in time means going towards the singularity.
Hah. I left off 3 zeros from that google query. Here's the corrected one:l ight%5E4+%2F+%28gravitational+constant+*+100000000 0000+solar+mass+*+4%29%29+%2F+gravity+on+earth
http://www.google.com/search?hl=en&q=%28speed+of+
Giving you about 1.551 G's at the event horizon. My mistake.
As I understand it, for a trillion-solar-mass black hole, gravitational acceleration at the event horizon is only about 1G.
l ight%5E4+%2F+%28gravitational+constant+*+100000000 0+solar+mass+*+4%29%29+%2F+gravity+on+earth
Don't know where you got that idea. If you assume a simple non-rotating black hole, then the Schwarzschild radius (aka the event horizon) is the distance from the singularity at which the gravitational field is so powerful that the black hole's escape velocity is greater than the speed of light. r = 2GM/c^2, where r is the Schwarzschild radius - the distance from the singularity to the event horizon. You can even get this from the Newtonian escape velocity equation, just set v = c and solve for r.
Now, plug that radius into the standard acceleration formula: a = GM / r^2.
Result: a = c^4 / 4GM. a = acceleration due to gravity at the event horizon, M = mass of black hole.
And here's a nice google query to tell you how much acceleration there would be at the event horizon of a black hole of a trillion solar masses: http://www.google.com/search?hl=en&q=%28speed+of+
So about 1551 G's. If you add more mass, the acceleration drops off, of course.
It's not that you can't accellerate hard enough to overcome gravity, but the effects of a massive object on space itself that makes a black hole inescapable.
Yes, I see your point now. Say you're in a spaceship just inside the event horizon of that trillion sun hole above, and decide to gun the engine to 2000 G's to get the hell out. Why can't you? And the answer is that it's because of a the way space is curved inside the event horizon, so yeah, Newtonian mechanics can't cover this situation. Light can't change its speed, only it's direction. You can change either one, but are still screwed for different reasons.
There's a Firefox plugin called CookieCuller that I find very convienent. Basically, it deletes all your cookies when you close the browser (or perhaps when you start it up.. either way). It will also allow you to see the current cookies easily and to set individual ones as "protected", meaning it won't touch these.
It's extremely useful, as it will allow you to keep some persistent cookies (like your slashdot login, for example) while auto-killing the rest of them. All you have to do is login to a site, open the CookieCuller window, then find that site and tell it to protect that site's cookies. Voila. Very easy and handy.
An object does not have to reach escape velocity to escape a planet's gravitational pull.
;)
;)
You're partly right. You can NEVER escape a planet's gravitational pull. It just keeps pulling, no matter how far you go.
Escape velocity is the inital speed needed for a ballistic object to ensure that the gravitational pull of the planet will never be able to bring it to a complete stop, relative to the planet. As you move away from the planet, the gravitational force weakens. If you can move away faster than the force can slow you down, then the gravity of the planet can never stop you. That's the escape velocity.
However, for a rocket (or other powered device) to escape a planet's gravitational pull, as the GP said, all it has to do is provide enough vertical thrust to provide a positive acceleration. That acceleration does not have to accelerate it to the escape velocity - in fact, you could adjust it to compensate for the falling gravitational pull and so maintain a constant velocity of whatever you want, and (if you have sufficient power/fuel) you'll still escape.
In theory, you're partly correct here. If you could overcome gravity to provide a 1 foot per second squared upward accelleration, then yeah, you'd get to outer space. Eventually. It'd take one hell of a lot of fuel though, because you're only barely overcoming gravity. It's not actually *possible* because no ship exists that can do that and also have enough fuel to do it.
Any acceleration larger than gravity will get you there eventually if you assume enough fuel. And as gravity drops off due to distance, eventually you'll be travelling faster than escape velocity for the given height you happen to be at. And then you're free.
That doesn't work for a black hole because all of that is based on Newtonian mechanics, which do not apply in the large gravitational fields close to the event horizon. There, you must use General Relativity, which is counter to our everyday common sense view of the world (precisely because on our scales, it's irrelevant). I don't know enough about GR to demonstrate why this is, however.
The main reason is similar to the above: You don't have enough fuel. And not just because the technology doesn't exist, but because inside the event horizon, the acceleration due to gravity is so high that even light itself isn't moving fast enough to go "up". No amount of acceleration will let you make any forward progress at all, because you cannot possibly give it enough speed to exceed the speed of light. So you can't even go up at 1 foot per second, you can only go down.
To put it another way, inside the event horizon, space is bent in such a way that moving away from the singularity is no longer an available option.
Outside the event horizon, the normal, simple, equations still apply, more or less. The gravity is high, but the concept is the same. With a higher gravity comes a higher escape velocity, that's all. Also time dilation, but that's rather irrelevent to this discussion.
Google for "Duluc Dry Pile".
Also google for "Oxford Electric Bell". This particular type of battery has been ringing a bell (albeit inaudibly) in the foyer of a lab in Oxford for over 160 years.
The gist of it is that you get small circles of zinc foil, silver foil, and paper. Then you stack 'em up (silver, zinc, paper, repeat). Next you stick the whole thing in a glass tube and compress it. You want several thousand of them, basically. Once you're done, coat the whole thing in plastic to prevent oxidation from eating it away.
What you end up with is a battery that will power something reasonably small for a long, long, long time. Certainly could power a simplistic clock for a thousand years. Once your clock goes off, you make some sort of signal. Audio perhaps, since that's probably more reliable than radio would be over that time period.