The Fairness Doctrine cannot be applied to Internet blogs because it violates the basic tests that the Supreme Court has come up with for regulating speech:
* TV and radio can be regulated because they are "pervasive" (the signal comes into your house whether you want it or not) and "scarce" (there is only so much useful spectrum in any given area, so only so many voices can be heard.) Internet blogs are not pervasive (you have to seek them out) and they certainly aren't scarce (anyone who wants to can build a blog using free tools.)
* Commercial speech can be regulated. Not applicable here.
* Dangerous/inciting/traitorous speech ("fire in a crowded theater", "clear and present danger") can be regulated. Not applicable here.
* Obscenity. Not applicable here.
Note that, unlike the Internet taxation issue, this is a basic Constitutional problem. Unless one of the rules above is violated, the Supreme Court will knock down any attempt to regulate speech on the Internet. So I don't think this much matters. Even if this were a majority of people rather than just 30%, they're not going to get any kind of law passed to regulate Internet blog speech.
I randomly generate passwords and the answers to the "personal" questions, and then PGP email them to myself. The PGP email includes the name of the site and the date that the password is effective. If I have to change a password, I send myself a new email but include in it the old password(s), along with the date they were effective, in the body. I started tracking "old" passwords as well because I found that sometimes, I needed to resurrect an old, decommissioned system from years ago, and it's really handy to have all the possible passwords for it in one place.
The way I figure it, encrypted email is a "solved" problem, so why not leverage the existing infrastructure?
"Essex", "Sussex", and "Scunthorpe" are some "real" British names that also trip profanity filters.
Most English taboo words are very short. Some -- particularly "sex", "tit", and "shit" -- are particularly likely to occur when combining two words, or when translating from other languages, because the patterns are so simple.
So if you're going to build a profanity filter, at least build in some kind of override mechanism that can be used for these cases.
Forging packets is better than blocking, when it works, because it can be done out-of-band. If you block the flow, you have to put the logic into an in-band device -- a router or switch that's passing the traffic. If you do it out-of-band, you can have some external device make the determination based on a tap or netflow export, and forge packets, without needing to add load or functionality to your in-band devices. [Adding a netflow export may be an additional load, but the netflow exports can then be used by multiple apps, so you can only pay the cost once for many apps.]
Servers run at low capacity for two important reasons:
* User load/demand is variable. A lot of the capacity sizing is not for average demand but for peak demand. For example, mail servers see a lot more use at 1pm on Monday than at 5am on Sunday. Mail servers need enough capacity to deliver an all-company email from the CEO in a timely manner. If you reduce capacity to "even it out", big spikes in email, such as that all-company email from the CEO, cause mail delivery to be delayed many hours. The same applies to many applications -- the servers housing financial apps, for example, might see low utilization most of the year, but when quarterly reports are due, the finance people will be unhappy because the servers are running so slowly. Servers doing network management can go crazy during event storms such as major outages, which is when you most need them to be responsive. Many/most other kinds of servers have their own patterns of variable demand.
* Demand increases over time. Upgrades are far more expensive than energy cost, not just because of new hardware, but because of labor and downtime. Over-specifying a server up-front lets the system go longer without an upgrade, which is cheaper.
Public key encryption can be broken by anyone with sufficient time and computing power. PGP, SSL, SMIME, et. al. are all inherently breakable. The theory is that the secrets protected by public key encryption have a relatively limited monetary value, so it's not worthwhile for an attacker to spend massive resources to try to get access to secrets that are probably worth less than the cost of breaking them.
Guess what? To the US government, uncovering possible information related to terrorism has a massive monetary value. That means that the NSA and other related government agencies have ample incentive to bring correspondingly massive computing resources to bear.
So while sidechannels such as keyloggers and tempest-style attacks are probably cheaper, I bet that the US government could crack a PGP key if it had a good reason to do so.
There is supposed to be an international registry of known satellites, although not all countries use it consistently, especially for military satellites.
Pretending that a spy satellite is a different kind of satellite probably wouldn't work too well. First, different kinds of satellites use different orbits. Even more importantly, non-military US satellites have lots of publicly available information. Non-military satellites are usually either scientific instruments or commercial assets. The paper trail on a "real" non-military satellite would be hard to reproduce in a convincing way.
NASA needs to spearhead projects that are useful, in collaboration with the rest of the space-viewing world. The fact that there isn't a loud voice shouting about this concept to the pols is embarrassing.
What makes you think this isn't already happening? NASA already does this. On the national level, the US has the Near Earth Object program headed out of NASA's JPL. The Spaceguard Foundation acts on the international level.
NASA has a fair number of other projects that are immediately "useful", as opposed to indirectly useful, as part of the Earth Observing System. The TRMM project, for example, monitors tropical rain, which is useful for predicting hurricanes.
It's interesting to me that over the millions of years of evolution life has gone through, we're still using the same basic outlines for anatomy.
100 million years is the recent past, in evolutionary terms. See the Timeline of evolution. Single-celled life evolved about 4 billion years ago. The even bigger leap to multi-celled life was 1 billion years ago. By 100 million years ago, we already had all the big developments except human brains: plants, fish, insects, amphibians, reptiles, mammals, birds, and flowers. So 100 million years ago isn't that old, in evolutionary terms.
Part of why people don't want to pay for access to "premium" newspapers is because they can access other "premium" newspapers for free. Why would I pay to read the New York Times when I can access the BBC, CNN, and Foxnews for free? For online charging to work, newspapers need to all illegally collude.
Consumer Reports doesn't have much competition at all, let alone free competition, so they can get away with charging.
Sometimes when looking at a translation dictionary you get the impression that one word translates precisely into another word. That is not true, the two words may have vastly different connotation. Also, connotations may change over time. I am no biblical scholar, but I believe that it has been well established that a more accurate translation of the ancient Hebrew text refers to "murder". not "kill".
As someone who speaks Hebrew, yes. The relevant words in the so-called "10 commandments" are "lo tir'tzakh" (Ashkenazi pronunciation: "lo sir'tzakh.") This translates closer to "don't murder" than "don't kill." When the killing is done for war or as an execution (i.e. justifiable) the form "la'harog" tends to be used rather than "l'r'tzoakh." "la'harog" can also sometimes be used to connote unjustified murder, but "l'r'tzoakh" is never justifiable killing. The English words "kill" and "murder" are actually quite parallel, in that "kill" can be used both for justified and unjustified homicide, while "murder" is consistently unjustified.
[Note: I didn't follow any of the official rule schemes for the above transliterations.]
A geosynchronous orbit stays above the equator, hovering over a particular spot on the Earth's surface. As such, it will spend, on average, exactly 50% of the time in sunlight (ie. when it is sunny at the point on the Earth directly below it), and 50% of the time in darkness (ie. when the Earth is between the satellite and the sun)./blockquote Even with your later correction, you've described a geostationary orbit. The article said geosynchronous orbit. Not all geosynchronous orbits are geostationary. An inclined geosynchronous orbit, such as the one planned for the Solar Dynamics Observatory spacecraft, can maintain continuous coverage of the Sun while also staying in almost constant view of the ground station. See google or wikipedia for more information.
And man would I kill for some real Sugar in my Coke too. The HFC crap they use instead tastes like garbage. Only took one trip to Japan with REAL Coke with sugar in it makes the stuff we have in the US impossible to drink now.
Around Passover time, you can find coca cola in the U.S. with real sugar instead of HFCS (high fructose corn syrup). You will still have to travel to certain major metro areas (i.e. the ones with lots of Jews.) Google for "passover coca cola" for more information.
There is something of an arms race between website content providers and users. Providers want revenue via various ad mechanisms. Users don't want intrusive ads, and the knowledgeable ones install tech that blocks intrusive ads -- popup blockers, adblock, even noscript with flash blocking enabled. Content providers respond by developing new ways to be intrusive -- popups via flash, DHTML-based ads, and the like. Users develop new client-side tech to block known threats, and the cycle continues.
So this is just a new step in the arms race, where some content providers will try to block users with tech that blocks ads, or encourages ad blocking, instead of developing better ad tech.
Problem one for this approach: such tech gradually becomes more mainsteam. Popup blockers are the best example of ad blocking tech becoming mainstream. Popup blockers started as third-party software, but first FF and then IE included integrated popup blocking. The author's own website endorses popup blocking (I'm not going to provide a direct link 'cuz I don't want to provide pagecount to this jerk), which is pretty ironic, since popups are all about ads. Now, all of the biggest browsers including IE can block ads via extensions; the complaint here is that FF "endorsed" adblock, not that adblock is available. Content providers are welcome to block FF, but they have to realize that tech like adblock is going to become more popular as a direct result of the intrusiveness of ads.
A more logical response to adblock is to make less-intrusive ads (i.e. text ads, simple image ads) that are harder to block, and/or less intrusive. There is a reason why popup blocking is standard in all major browsers, but adblock and similar tech is not -- popups are very intrusive, while regular ads are less so. If content providers want ad-related revenue, they have to provide ads that don't annoy their potential customers. This is why superbowl ads, and many TV ads, are funny and interesting instead of annoying.
On a personal note, I like to support websites, so I browse using FF but no longer use adblock as of about a year ago. That said, popups and flash exceed my tolerance threshold, so I use noscript with flash blocking enabled by default, and leave the popup blocker enabled.
Perhaps I'm missing something critical here, but wouldn't the complexity of this attack make it largely un-useful. In order to switch the user's DNS back and forth between external and internal, you would need control of that user's DNS server, or at least a DNS server further up the chain.
RTFA. The attacker doesn't manipulate the user's DNS, the attacker manipulates his/her own DNS. The attacker uses records with low or 0 TTLs, so the user's DNS doesn't cache them as per spec. The trick is that the attacker changes his/her own DNS to point at the user's own names or addresses.
Beyond that, some knowledge of the internal network is required so the attacker knows where to go.
Yes. Which, for targetted attacks (think corporate espionage or hostile national governments) is not unrealistic.
Does the javascript exploit change the user's DNS server to something malicious?
RTFA. No; the attacker manipulates his/her own DNS, using a low TTL.
Any DNS server that *can't* be configured to ignore requests for internal names from external addresses is pretty broken.
That's not the problem. The problem is requests from internal addresses for external names that resolve to internal addresses. How do you block *that*?
It still relies on the user going to a malicious website in the first place.
If you read the original article, you will note that they generated exploit stats by utilizing an ad network. You don't need to visit a "bad" website, you just need a "bad" ad while visiting a normal website.
And considering that I've already (after reading the article mind you) changed my DNS servers to not return results matching our internal address range for lookups resolved from external hosts, its ever less useful.
Cool! What server do you use, and how did you configure it to do this?
Worse than that, they are assuming that the OS itself is not caching the result. I sometimes have to manually flush my cache (OS X) when playing with DNS records. OS X can't be the only system that caches lookups. The article explicitly says that the attack assumes low or 0 TTLs. Your OS cache should not be caching 0 TTLs per RFC1034. Normally, you need to flush the cache because you are editing a record with a high(er) TTL, so your local cache legitimately retains the old version of the record. Some caches do ignore record TTLs, though.
Now they do say that the attacker DNS returns more then one A record for each request. But they are ignoring the fact that the serial number of the zone would have to change for a refresh to not get cached.
DNS servers cache based on the resource record's TTL, not based on the zone's SOA's serial. The serial is used by secondaries.
And even if they did create a new zone record for each visit, with the target's IP (seems unlikely), all the servers back to the client would need to respect it. Again, my ISP Qwest, has a bad habit of ignoring the TTL in my zone files.
The article assumes that third-party caches respect low and 0 TTLs. RFC1034 and RFC1035 say that a TTL of 0 should work. Many (most?) DNS caching servers obey the RFCs and respect low/0 TTLs. Changing this default would be a valid workaround for this problem, but would break legitimate use of low/0 TTLs (i.e. for high-availability solutions to do rapid failover.)
Computing is driven by requirements -- we want a program or system that does X, and it needs to do it in total time Y, cost less than Z, and respond to operator input in less than W milliseconds. This in turn drives us to design programs, OSs, drivers, and systems that run "quickly" and consume resources such as RAM and disk space within certain limits. To meet this requirements, we need to quantitatively measure the performance of hardware and code to determine time and resource consumption. The tools with which we do this require mathematics. So computing inherently needs math to analyze potential solutions against qualitative requirements. This is pervasive at all levels of CS, whether it's a logic path that needs to complete a calculation before a clock cycle deadline, a sort that needs to complete in a reasonable amount of time, a network transfer that needs to deal with latency and bandwidth constraints, an OS that needs to grab data off a disk as quickly and fairly as possible to meet the various demands of running programs, or a user interface that needs to respond to user input in a timely manner while creating a DVD image.
There are also plenty of areas of CS that are even more fundamentally mathematical in nature. Network dynamic routing protocols don't work without various graph-related algorithms. Cryptography leans heavily on number theory. Sets/relations revolutionized databases. It's hard to imagine these advances in CS occurring without the strong connection between CS and mathematics.
That said, articles are notoriously bad at summarizing books. After all, if the book could be meaningfully summarized in a few paragraphs, the book wouldn't have been published; instead, the author would have just written an article to begin with. Certainly, there are aspects of computing that are heavily abstracted away from CS's mathematical underpinnings -- for example, non-modal application user interfaces, usability, software engineering techniques, and access controls. Perhaps this guy has a method for describing computer systems that makes it easier to think about these problems. Or perhaps not -- even if he has a "new model," if it doesn't make it easier to solve problems in CS, it's not particularly useful. Hard to tell without more detail.
3. As has been mentioned time and again, until developers actually embrace multi-threading this will be relatively useless. Tests from various hardware sites have shown that going from the Core 2 Duo to the Core 2 Quad offers very little benefit except for a very small subset of users... who should probably be running workstations anyway (Video editing, 3D rendering, etc.)
RTFA. The article claims:
"The 'software' challenge is: Can you manage all the different tasks and workers so that the job is completed in 3 minutes instead of 300?" Vishkin continued. "Our algorithms make that feasible for general-purpose computing tasks for the first time."... To show how easy it is to program, Vishkin is also providing access to the prototype to students at Montgomery Blair High School in Montgomery County, Md.
Parallel computing has been around for a while. One of the challenges of parallel computing has always been that it is inherently harder to code. These guys acknowledged this, but they say their prototype is "easy" to program. We'll see if they're right.
It may be an old trick, but it's now an illegal trick. Fax spam is illegal, since unlike telephone spam and email spam, there are easy-to-quantify material costs associated with fax spam. Basically, you can't send unsolicited faxes. See the FCC's rules on unwanted faxes.
While you can block caller-id of your fax machine and anonymize its identity info, if you're going to run the fax in a loop as described, it would be possible for the receiving business to notice what's going on and call the phone company to find out who you are. Not only are you doing something illegal, but you're clearly aware of it, because you're trying to hide your identity. From a legal perspective, this is called "bad faith", and makes it more likely that you can be successfully prosecuted.
So while this may have worked 20 years ago, doing this kind of thing in 2007 may be a bad idea.
Going back some time, all software developed for the US government, including NASA, had to be released for free in source form unless specially exempted (i.e. for military or strategic reasons.) At some point, this government-wide requirement went away -- I'm not sure when or why. If anyone remembers, please speak up.
Where I work, not only can you drink with the boss, but when good people leave, we stay friends. We encourage them to come back if they want to. And most of the people are good people. And, in fact, most of them come back.
One of the current bosses himself left and came back.
One of the guys left, came back, left, and we're in talks to bring him back again.
One guy "left" on a Friday, and was back at work on Monday -- they made him an offer he couldn't refuse.
IMHO, it's in the interest of an employer to do this kind of thing. It's a lot easier to bring a former employee back up to speed than to train a completely new person. But, of course, different work situations vary.
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The Fairness Doctrine cannot be applied to Internet blogs because it violates the basic tests that the Supreme Court has come up with for regulating speech:
* TV and radio can be regulated because they are "pervasive" (the signal comes into your house whether you want it or not) and "scarce" (there is only so much useful spectrum in any given area, so only so many voices can be heard.) Internet blogs are not pervasive (you have to seek them out) and they certainly aren't scarce (anyone who wants to can build a blog using free tools.)
* Commercial speech can be regulated. Not applicable here.
* Dangerous/inciting/traitorous speech ("fire in a crowded theater", "clear and present danger") can be regulated. Not applicable here.
* Obscenity. Not applicable here.
Note that, unlike the Internet taxation issue, this is a basic Constitutional problem. Unless one of the rules above is violated, the Supreme Court will knock down any attempt to regulate speech on the Internet. So I don't think this much matters. Even if this were a majority of people rather than just 30%, they're not going to get any kind of law passed to regulate Internet blog speech.
I randomly generate passwords and the answers to the "personal" questions, and then PGP email them to myself. The PGP email includes the name of the site and the date that the password is effective. If I have to change a password, I send myself a new email but include in it the old password(s), along with the date they were effective, in the body. I started tracking "old" passwords as well because I found that sometimes, I needed to resurrect an old, decommissioned system from years ago, and it's really handy to have all the possible passwords for it in one place.
The way I figure it, encrypted email is a "solved" problem, so why not leverage the existing infrastructure?
"Essex", "Sussex", and "Scunthorpe" are some "real" British names that also trip profanity filters.
Most English taboo words are very short. Some -- particularly "sex", "tit", and "shit" -- are particularly likely to occur when combining two words, or when translating from other languages, because the patterns are so simple.
So if you're going to build a profanity filter, at least build in some kind of override mechanism that can be used for these cases.
Forging packets is better than blocking, when it works, because it can be done out-of-band. If you block the flow, you have to put the logic into an in-band device -- a router or switch that's passing the traffic. If you do it out-of-band, you can have some external device make the determination based on a tap or netflow export, and forge packets, without needing to add load or functionality to your in-band devices. [Adding a netflow export may be an additional load, but the netflow exports can then be used by multiple apps, so you can only pay the cost once for many apps.]
Servers run at low capacity for two important reasons:
* User load/demand is variable. A lot of the capacity sizing is not for average demand but for peak demand. For example, mail servers see a lot more use at 1pm on Monday than at 5am on Sunday. Mail servers need enough capacity to deliver an all-company email from the CEO in a timely manner. If you reduce capacity to "even it out", big spikes in email, such as that all-company email from the CEO, cause mail delivery to be delayed many hours. The same applies to many applications -- the servers housing financial apps, for example, might see low utilization most of the year, but when quarterly reports are due, the finance people will be unhappy because the servers are running so slowly. Servers doing network management can go crazy during event storms such as major outages, which is when you most need them to be responsive. Many/most other kinds of servers have their own patterns of variable demand.
* Demand increases over time. Upgrades are far more expensive than energy cost, not just because of new hardware, but because of labor and downtime. Over-specifying a server up-front lets the system go longer without an upgrade, which is cheaper.
Public key encryption can be broken by anyone with sufficient time and computing power. PGP, SSL, SMIME, et. al. are all inherently breakable. The theory is that the secrets protected by public key encryption have a relatively limited monetary value, so it's not worthwhile for an attacker to spend massive resources to try to get access to secrets that are probably worth less than the cost of breaking them.
Guess what? To the US government, uncovering possible information related to terrorism has a massive monetary value. That means that the NSA and other related government agencies have ample incentive to bring correspondingly massive computing resources to bear.
So while sidechannels such as keyloggers and tempest-style attacks are probably cheaper, I bet that the US government could crack a PGP key if it had a good reason to do so.
There is supposed to be an international registry of known satellites, although not all countries use it consistently, especially for military satellites.
Pretending that a spy satellite is a different kind of satellite probably wouldn't work too well. First, different kinds of satellites use different orbits. Even more importantly, non-military US satellites have lots of publicly available information. Non-military satellites are usually either scientific instruments or commercial assets. The paper trail on a "real" non-military satellite would be hard to reproduce in a convincing way.
What makes you think this isn't already happening? NASA already does this. On the national level, the US has the Near Earth Object program headed out of NASA's JPL. The Spaceguard Foundation acts on the international level.
NASA has a fair number of other projects that are immediately "useful", as opposed to indirectly useful, as part of the Earth Observing System. The TRMM project, for example, monitors tropical rain, which is useful for predicting hurricanes.
DISCLOSURE: my job is in aerospace.
100 million years is the recent past, in evolutionary terms. See the Timeline of evolution.
Single-celled life evolved about 4 billion years ago. The even bigger leap to multi-celled life was 1 billion years ago. By 100 million years ago, we already had all the big developments except human brains: plants, fish, insects, amphibians, reptiles, mammals, birds, and flowers. So 100 million years ago isn't that old, in evolutionary terms.
Part of why people don't want to pay for access to "premium" newspapers is because they can access other "premium" newspapers for free. Why would I pay to read the New York Times when I can access the BBC, CNN, and Foxnews for free? For online charging to work, newspapers need to all illegally collude.
Consumer Reports doesn't have much competition at all, let alone free competition, so they can get away with charging.
As someone who speaks Hebrew, yes. The relevant words in the so-called "10 commandments" are "lo tir'tzakh" (Ashkenazi pronunciation: "lo sir'tzakh.") This translates closer to "don't murder" than "don't kill." When the killing is done for war or as an execution (i.e. justifiable) the form "la'harog" tends to be used rather than "l'r'tzoakh." "la'harog" can also sometimes be used to connote unjustified murder, but "l'r'tzoakh" is never justifiable killing. The English words "kill" and "murder" are actually quite parallel, in that "kill" can be used both for justified and unjustified homicide, while "murder" is consistently unjustified.
[Note: I didn't follow any of the official rule schemes for the above transliterations.]
Around Passover time, you can find coca cola in the U.S. with real sugar instead of HFCS (high fructose corn syrup). You will still have to travel to certain major metro areas (i.e. the ones with lots of Jews.) Google for "passover coca cola" for more information.
There is something of an arms race between website content providers and users. Providers want revenue via various ad mechanisms. Users don't want intrusive ads, and the knowledgeable ones install tech that blocks intrusive ads -- popup blockers, adblock, even noscript with flash blocking enabled. Content providers respond by developing new ways to be intrusive -- popups via flash, DHTML-based ads, and the like. Users develop new client-side tech to block known threats, and the cycle continues.
So this is just a new step in the arms race, where some content providers will try to block users with tech that blocks ads, or encourages ad blocking, instead of developing better ad tech.
Problem one for this approach: such tech gradually becomes more mainsteam. Popup blockers are the best example of ad blocking tech becoming mainstream. Popup blockers started as third-party software, but first FF and then IE included integrated popup blocking. The author's own website endorses popup blocking (I'm not going to provide a direct link 'cuz I don't want to provide pagecount to this jerk), which is pretty ironic, since popups are all about ads. Now, all of the biggest browsers including IE can block ads via extensions; the complaint here is that FF "endorsed" adblock, not that adblock is available. Content providers are welcome to block FF, but they have to realize that tech like adblock is going to become more popular as a direct result of the intrusiveness of ads.
Also, with FF estimated at 14% market share, blocking FF means blocking a whole lot of potential customers.
A more logical response to adblock is to make less-intrusive ads (i.e. text ads, simple image ads) that are harder to block, and/or less intrusive. There is a reason why popup blocking is standard in all major browsers, but adblock and similar tech is not -- popups are very intrusive, while regular ads are less so. If content providers want ad-related revenue, they have to provide ads that don't annoy their potential customers. This is why superbowl ads, and many TV ads, are funny and interesting instead of annoying.
On a personal note, I like to support websites, so I browse using FF but no longer use adblock as of about a year ago. That said, popups and flash exceed my tolerance threshold, so I use noscript with flash blocking enabled by default, and leave the popup blocker enabled.
- Morty
RTFA. The attacker doesn't manipulate the user's DNS, the attacker manipulates his/her own DNS. The attacker uses records with low or 0 TTLs, so the user's DNS doesn't cache them as per spec. The trick is that the attacker changes his/her own DNS to point at the user's own names or addresses.
Yes. Which, for targetted attacks (think corporate espionage or hostile national governments) is not unrealistic.
RTFA. No; the attacker manipulates his/her own DNS, using a low TTL.
That's not the problem. The problem is requests from internal addresses for external names that resolve to internal addresses. How do you block *that*?
If you read the original article, you will note that they generated exploit stats by utilizing an ad network. You don't need to visit a "bad" website, you just need a "bad" ad while visiting a normal website. Cool! What server do you use, and how did you configure it to do this?
For now, bind9 does not support this. See the relevant thread.
Worse than that, they are assuming that the OS itself is not caching the result. I sometimes have to manually flush my cache (OS X) when playing with DNS records. OS X can't be the only system that caches lookups.
The article explicitly says that the attack assumes low or 0 TTLs. Your OS cache should not be caching 0 TTLs per RFC1034. Normally, you need to flush the cache because you are editing a record with a high(er) TTL, so your local cache legitimately retains the old version of the record. Some caches do ignore record TTLs, though.
- Morty
Now they do say that the attacker DNS returns more then one A record for each request. But they are ignoring the fact that the serial number of the zone would have to change for a refresh to not get cached.
DNS servers cache based on the resource record's TTL, not based on the zone's SOA's serial. The serial is used by secondaries.
And even if they did create a new zone record for each visit, with the target's IP (seems unlikely), all the servers back to the client would need to respect it. Again, my ISP Qwest, has a bad habit of ignoring the TTL in my zone files.
The article assumes that third-party caches respect low and 0 TTLs. RFC1034 and RFC1035 say that a TTL of 0 should work. Many (most?) DNS caching servers obey the RFCs and respect low/0 TTLs. Changing this default would be a valid workaround for this problem, but would break legitimate use of low/0 TTLs (i.e. for high-availability solutions to do rapid failover.)
- Morty
Computing is driven by requirements -- we want a program or system that does X, and it needs to do it in total time Y, cost less than Z, and respond to operator input in less than W milliseconds. This in turn drives us to design programs, OSs, drivers, and systems that run "quickly" and consume resources such as RAM and disk space within certain limits. To meet this requirements, we need to quantitatively measure the performance of hardware and code to determine time and resource consumption. The tools with which we do this require mathematics. So computing inherently needs math to analyze potential solutions against qualitative requirements. This is pervasive at all levels of CS, whether it's a logic path that needs to complete a calculation before a clock cycle deadline, a sort that needs to complete in a reasonable amount of time, a network transfer that needs to deal with latency and bandwidth constraints, an OS that needs to grab data off a disk as quickly and fairly as possible to meet the various demands of running programs, or a user interface that needs to respond to user input in a timely manner while creating a DVD image.
There are also plenty of areas of CS that are even more fundamentally mathematical in nature. Network dynamic routing protocols don't work without various graph-related algorithms. Cryptography leans heavily on number theory. Sets/relations revolutionized databases. It's hard to imagine these advances in CS occurring without the strong connection between CS and mathematics.
That said, articles are notoriously bad at summarizing books. After all, if the book could be meaningfully summarized in a few paragraphs, the book wouldn't have been published; instead, the author would have just written an article to begin with. Certainly, there are aspects of computing that are heavily abstracted away from CS's mathematical underpinnings -- for example, non-modal application user interfaces, usability, software engineering techniques, and access controls. Perhaps this guy has a method for describing computer systems that makes it easier to think about these problems. Or perhaps not -- even if he has a "new model," if it doesn't make it easier to solve problems in CS, it's not particularly useful. Hard to tell without more detail.
3. As has been mentioned time and again, until developers actually embrace multi-threading this will be relatively useless. Tests from various hardware sites have shown that going from the Core 2 Duo to the Core 2 Quad offers very little benefit except for a very small subset of users... who should probably be running workstations anyway (Video editing, 3D rendering, etc.)
RTFA. The article claims:
"The 'software' challenge is: Can you manage all the different tasks and workers so that the job is completed in 3 minutes instead of 300?" Vishkin continued. "Our algorithms make that feasible for general-purpose computing tasks for the first time."
To show how easy it is to program, Vishkin is also providing access to the prototype to students at Montgomery Blair High School in Montgomery County, Md.
Parallel computing has been around for a while. One of the challenges of parallel computing has always been that it is inherently harder to code. These guys acknowledged this, but they say their prototype is "easy" to program. We'll see if they're right.
It may be an old trick, but it's now an illegal trick. Fax spam is illegal, since unlike telephone spam and email spam, there are easy-to-quantify material costs associated with fax spam. Basically, you can't send unsolicited faxes. See
the FCC's rules on unwanted faxes.
While you can block caller-id of your fax machine and anonymize its identity info, if you're going to run the fax in a loop as described, it would be possible for the receiving business to notice what's going on and call the phone company to find out who you are. Not only are you doing something illegal, but you're clearly aware of it, because you're trying to hide your identity. From a legal perspective, this is called "bad faith", and makes it more likely that you can be successfully prosecuted.
So while this may have worked 20 years ago, doing this kind of thing in 2007 may be a bad idea.
There are a whole lot of NASA Open-source projects. For example, see http://opensource.arc.nasa.gov/ and http://opensource.gsfc.nasa.gov/ .
Going back some time, all software developed for the US government, including NASA, had to be released for free in source form unless specially exempted (i.e. for military or strategic reasons.) At some point, this government-wide requirement went away -- I'm not sure when or why. If anyone remembers, please speak up.
Whoa.
Where I work, not only can you drink with the boss, but when good people leave, we stay friends. We encourage them to come back if they want to. And most of the people are good people. And, in fact, most of them come back.
One of the current bosses himself left and came back.
One of the guys left, came back, left, and we're in talks to bring him back again.
One guy "left" on a Friday, and was back at work on Monday -- they made him an offer he couldn't refuse.
IMHO, it's in the interest of an employer to do this kind of thing. It's a lot easier to bring a former employee back up to speed than to train a completely new person. But, of course, different work situations vary.