Wire length. For low voltages, the voltage drop is important, which means that a longer cable needs to be thicker. If you replaced the 2 meter long cable from the wallwart to your TV with a 20m cable you would have to have a much bigger cable. RVs are small, so the cables in them are short, letting you get away with low voltage.
Actually it would be worse. For 220V AC the wiring is usually sized so it does not melt under full load (full load results in a specified temperature increase), which means that you can use the same size wire for a 1m or a 20m required.length. For low voltage (12V and especially 5V) the wire would have to be much bigger than the "don't melt" requirement since now the voltage drop would be more important. Also, a 20m wire would need to be thicker than a 1m wire.
Low voltage distribution won't work, even just inside the home for high power devices.
Low voltage both needs a bigger wire due to higher current and at the same time is more sensitive to voltage drop (5V drop for a 12V line is much worse than 5V drop for a 220V line). So, plugging in a computer (300-500W more if it's a gaming rig with four video cards) or a big TV (150W) or AC (1kW or more) or electric kettle (2kW) or something else that uses a lot of power is not practical with 12V.
OK, so let's up the voltage to 48V. Now the TV needs 3A, a PC needs 10A and the kettle needs 42A with permissible voltage drop of 4.8V. This can be doable (except the kettle), but you still need big wires and outlets. Also, you still need DC-DC converters for most devices as they do not run on 48V internally.
As for having three different voltages (12, 48, 220 AC), that would be really inconvenient. Do you want to be able to plug in you vacuum or kettle in every room? Well, every room has to have a 220V outlet. And those are where the highest power devices will be plugged in. OK, your phone can charge on 12V. Do you want to run a separate cable just for the phone? How much power will it save? When the cost of running the wire will pay off in the conversion savings?
As for battery backing the low voltage and not backing the 220V - well, if my heat pump, AC, furnace and servers are connected to it, while my phone charger is connected to 12V, guess which line I will want to have backup power?
Also, backward compatibility. If my radio can only work on AC, then I am going to need a 220V outlet for the radio.
Would it not be possible to repair the genes? If DNA gets messed up, why not keep a backup with multiple copies and (important) checksums to refresh the copies stored in the cells once in a while so it does not become too corrupt? The DNA is a few gigabytes IIRC, easily stored in a small chip.
Now, currently I do not know of a way to actually repair the DNA in cells, but maybe at some time in the future some smart people figure this out...
Yea, there are exceptions, but the "norm" is that girls are not into technology. I am not saying the "norm" is good, but it is what it is.
Also, women are diffrent from men in physical strength. Sure, there are a lot of women who could beat me up or lift more weight than I can, but if you chose a man and a woman at random there is over 50% chance that the man would be stronger than the woman. I do not know if this also applies to the ability to program.
In my opinion the current system, while not perfect, is still better than privately owned police (who would only do stuff for money, therefor, only for people who have (lots of) money).
Companies shouldshould try to pay as little as possible. That's the system: it depends on human greed at every exchange. Any system that doesn't is purest foolishness.
Sure, however, while Free Market looks good in theory, so does Communism. The problem with both is that they are not achievable in reality, we can only have weird mangled versions of them.
Let's have private companies in charge of everything! That will work great - they will not try to make more profit than they have to and if they still do, we can vote them out in the next election.
So, I am sure that I won't have to pay $100000 in case of a fire, $20000 to have the police find the guy who beat me up (and another $20000 to have the court send him to jail) and $1M to repair a road.
A woman can be equal or better (stronger etc) than a man. There probably are a lot of women who could lift more than I can or beat me up. However, on average, women are weaker than men. Also, the strongest woman is most likely weaker than the strongest man. Why else there would be a need for segregation in sports? Have women compete against men in weightlifting, boxing etc.
And yet, there is a difference - even the law recognizes it. The "no item is lost" is not because it's intangible, but also because making a copy does not destroy the original. Compare these two events:
1. I copy a CD borrowed from a friend. The studio still has as many copies of the album as they had before. 2. I break into the studio, grab the master tape, leave a blank tape (the same type) (or copy the tape then erase it) and run away. The studio no longer has the album, but I only stole the music - they did not lose the physical tape.
To me, only the second event would be stealing while leaving all tangible items are in place.
And you cannot steal a "right" - the studio still has the right to copy the album, I cannot take it away from them without getting a new law passed, since the right is just how the law sees it. I can however, infringe on the right, or rather, the exclusivity of it by making my own illegal copies.
And if the cable company did not disconnect the cable after I cancelled the service, then I sure can watch TV without paying.
The difference between real theft and copyright infringement is that if you steal a physical item (say a DVD of a movie), the legit owner of the item no longer has it. He is then out the money he paid for it (paid money, no item). I steal a DVD from you, you can no longer play that DVD.
Copyright infringement is different in that here no item is lost - the studio still has as many copies of the movie as they had before I downloaded it. What the studio considers a loss is the potential profit they would have had if I bought the movie instead, however, that assumes: 1) That I would have bought the movie new for the full price (and not buy used or wait for the price to drop). 2) That the movie is available for sale at all in the store (how do I get the Star Wars Holiday Special legally?)
Remember - if I buy a movie used, the studio gets zero dollars from me.
Even so, most of the time the updates come out, there usually is at least one that requires a reboot. Compare that to Linux where only a kernel update requires a reboot (and as I understand, in the latest kernel versions it no longer requires a reboot).
Because most people already have a good desktop or laptop PC at home. PCs do not change as much as they used to, so you do not need to buy a new one (or even upgrade your current one) every year like you used to (unless you play games and really want to have as high FPS as possible). A PC now lasts for many years for common tasks like web browsing.
On the other hand, tablets and phones change a lot, while the hardware may not change as much (or rather, as noticeably), you cannot most of the time upgrade to a newer software version on your old device (like you can upgrade Windows Vista to 7 for example).
Of all people I personally know, the majority have a PC at home (those that don't are usually older than 70 years - didn't need or use a PC all their lives, do not care to start now). Sure, some also have tablets or smartphones.
The measurement of sales for something that most people already have is weird for me. Sure, you can measure sales of some new technology or limited-use things to see how they are doing, but to say that, for example, radio is dead because people are not buying new radios as much as they used to even though most people have a radio and use it (at least in the car) is a bit wrong. Most people already have a radio, a TV and a PC at home, just because sales are dropping may not indicate that the technology is dying, it may be that the devices people already have are still good enough.
Lithuania. Haven't heard of this happening here. However, in some cases, both drivers can be declared guilty. If the insurance company tries to say that the driver in front stopped for no reason to get insurance money, this still does not excuse the driver behind of not keeping a safe distance (well, what if the driver in front had a reason to brake?).
In my country if you hit a car in front of you, you are guilty for the accident because you failed to keep at a safe distance. It does not matter if the driver in front stepped on the brakes for no reason (in some cases you may be both declared guilty). The reasoning is that even if he stepped on the brakes for no reason at that time, what if there was a reason (pothole, someone on the road etc) that you could not see? You would still have hit the car in front of you.
In my country, speed cameras are preceded with a sign announcing the presence of said camera. The signs far enough away that you can slow down without hitting the brakes too hard (unless you were really speeding). The government said that, yes, more fines would be collected without those signs, however, the intended result is not to collect fines, but to make people drive slow, at least in that area. Which the signs do well.
Well, one man in my country had 0.84% BAC. Yea, twice the LD50 level. He was driving but could not find his way out of an (almost) empty parking lot and a bystander called the police.
The record BAC was 1.4%, though that guy was unconscious on the side of a road.
Yea, in my country hitting a car from behind makes you guilty (should have kept the distance), unless the other driver is drunk (drunk driver is always guilty) or he changed lanes too close in front of you and braked immediately.
That may not be fine as well, since unless IPv6 can cram both host IPs into the packet, existing sessions will get dropped (which may not happen with IPv4, since IPs stay the same). Also, that requires more complex firewall configuration (what's the probability that one of the IPs will not be entered?).
My back-of-a-napkin solution to this a few years ago was that there's an obvious business model for a few ISP to conspire to jointly provide dual-homing.
There are a few problems with this: 1. The ISPs must be willing to cooperate (unlike now, they only have to provide BGP access). 2. The customer still cannot change ISPs (now I can take my AS to another ISP if I do not like the current one or another pair of ISPs if I'm moving and the current ISPs do not provide service in the new location). 3. The failure of an ISP must trigger a BGP announce to stop traffic from coming to it. This may not happen. Currently we had multiple problems where the main ISP failed but did not announce that - out BGP router still though that the ISP is good. I had to write a script that checks if the internet is accessible and if not (for a few minutes) forces our BGP router to use the other ISP (done with prepends and priorities).
It's so great that all dangerous diseases are immediately obvious to averyone and the sick person himself. I mean there is no way that you could be sick, but not know that yet and transmit the disease to others. Right?
No, it's not. A NAT router works as a good firewall straight out of the box, you may not even need to configure it other than setting the admin password. Uplink IP is configured using DHCP, the router has its own DHCP server for internal network and no incoming connections are allowed.
I remember quite a few v4 IPs of my own machines, machines of the company I work for and of clients.
Adding all that to a DNS server would be a pain (either having one private server with all of them or adding to the servers of the appropriate client, assuming the client has a DNS server, some don't, after all a network of x Windows PCs and a single samba server does not really need DNS, especially if the network is just a bunch of Windows PCs with no server).
When a program does not work, I just run tcpdump (on both ends) and figure out the problem. A port scanner may only be able to scan a limited number of hosts at once, so if it spends a couple of hours trying to scan me, it won't scan others. Also, if the scanning is not automated (like a bot or virus) but is instead because somebody ran nmap, they might get bored and stop.
This is especially useful if the server does not have publicly accessible resources (that is, all incoming connections are limited by source IP). Dropping packets makes it look like that host isn't even there. Also useful in case of a DOS (that is not enough to completely saturate the uplink) as there are no packets going back.
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Wire length. For low voltages, the voltage drop is important, which means that a longer cable needs to be thicker. If you replaced the 2 meter long cable from the wallwart to your TV with a 20m cable you would have to have a much bigger cable. RVs are small, so the cables in them are short, letting you get away with low voltage.
Actually it would be worse. For 220V AC the wiring is usually sized so it does not melt under full load (full load results in a specified temperature increase), which means that you can use the same size wire for a 1m or a 20m required.length. For low voltage (12V and especially 5V) the wire would have to be much bigger than the "don't melt" requirement since now the voltage drop would be more important. Also, a 20m wire would need to be thicker than a 1m wire.
Low voltage distribution won't work, even just inside the home for high power devices.
Low voltage both needs a bigger wire due to higher current and at the same time is more sensitive to voltage drop (5V drop for a 12V line is much worse than 5V drop for a 220V line). So, plugging in a computer (300-500W more if it's a gaming rig with four video cards) or a big TV (150W) or AC (1kW or more) or electric kettle (2kW) or something else that uses a lot of power is not practical with 12V.
OK, so let's up the voltage to 48V. Now the TV needs 3A, a PC needs 10A and the kettle needs 42A with permissible voltage drop of 4.8V. This can be doable (except the kettle), but you still need big wires and outlets. Also, you still need DC-DC converters for most devices as they do not run on 48V internally.
As for having three different voltages (12, 48, 220 AC), that would be really inconvenient. Do you want to be able to plug in you vacuum or kettle in every room? Well, every room has to have a 220V outlet. And those are where the highest power devices will be plugged in. OK, your phone can charge on 12V. Do you want to run a separate cable just for the phone? How much power will it save? When the cost of running the wire will pay off in the conversion savings?
As for battery backing the low voltage and not backing the 220V - well, if my heat pump, AC, furnace and servers are connected to it, while my phone charger is connected to 12V, guess which line I will want to have backup power?
Also, backward compatibility. If my radio can only work on AC, then I am going to need a 220V outlet for the radio.
Would it not be possible to repair the genes? If DNA gets messed up, why not keep a backup with multiple copies and (important) checksums to refresh the copies stored in the cells once in a while so it does not become too corrupt? The DNA is a few gigabytes IIRC, easily stored in a small chip.
Now, currently I do not know of a way to actually repair the DNA in cells, but maybe at some time in the future some smart people figure this out...
Yea, there are exceptions, but the "norm" is that girls are not into technology. I am not saying the "norm" is good, but it is what it is.
Also, women are diffrent from men in physical strength. Sure, there are a lot of women who could beat me up or lift more weight than I can, but if you chose a man and a woman at random there is over 50% chance that the man would be stronger than the woman. I do not know if this also applies to the ability to program.
In my opinion the current system, while not perfect, is still better than privately owned police (who would only do stuff for money, therefor, only for people who have (lots of) money).
Companies shouldshould try to pay as little as possible. That's the system: it depends on human greed at every exchange. Any system that doesn't is purest foolishness.
Sure, however, while Free Market looks good in theory, so does Communism. The problem with both is that they are not achievable in reality, we can only have weird mangled versions of them.
Let's have private companies in charge of everything! That will work great - they will not try to make more profit than they have to and if they still do, we can vote them out in the next election.
So, I am sure that I won't have to pay $100000 in case of a fire, $20000 to have the police find the guy who beat me up (and another $20000 to have the court send him to jail) and $1M to repair a road.
Real buttons is why I am using a Nokia E90 communicator instead of something newer.
A bit better:
ssh your-router-ip
iptables -F FB /`
iptables -X FB
iptables -N FB
for ip in `whois -h whois.radb.net '!gAS32934' | grep
do
iptables -A FB -o eth0 -d $ip -j REJECT
done
iptables -I FORWARD -o eth0 -j FB
A woman can be equal or better (stronger etc) than a man. There probably are a lot of women who could lift more than I can or beat me up. However, on average, women are weaker than men. Also, the strongest woman is most likely weaker than the strongest man. Why else there would be a need for segregation in sports? Have women compete against men in weightlifting, boxing etc.
And yet, there is a difference - even the law recognizes it. The "no item is lost" is not because it's intangible, but also because making a copy does not destroy the original. Compare these two events:
1. I copy a CD borrowed from a friend. The studio still has as many copies of the album as they had before.
2. I break into the studio, grab the master tape, leave a blank tape (the same type) (or copy the tape then erase it) and run away. The studio no longer has the album, but I only stole the music - they did not lose the physical tape.
To me, only the second event would be stealing while leaving all tangible items are in place.
And you cannot steal a "right" - the studio still has the right to copy the album, I cannot take it away from them without getting a new law passed, since the right is just how the law sees it. I can however, infringe on the right, or rather, the exclusivity of it by making my own illegal copies.
And if the cable company did not disconnect the cable after I cancelled the service, then I sure can watch TV without paying.
The difference between real theft and copyright infringement is that if you steal a physical item (say a DVD of a movie), the legit owner of the item no longer has it. He is then out the money he paid for it (paid money, no item). I steal a DVD from you, you can no longer play that DVD.
Copyright infringement is different in that here no item is lost - the studio still has as many copies of the movie as they had before I downloaded it. What the studio considers a loss is the potential profit they would have had if I bought the movie instead, however, that assumes:
1) That I would have bought the movie new for the full price (and not buy used or wait for the price to drop).
2) That the movie is available for sale at all in the store (how do I get the Star Wars Holiday Special legally?)
Remember - if I buy a movie used, the studio gets zero dollars from me.
What if the company sends your report to /dev/null ? If this guy figured it out, so can someone who is less concerned with ethics.
Even so, most of the time the updates come out, there usually is at least one that requires a reboot. Compare that to Linux where only a kernel update requires a reboot (and as I understand, in the latest kernel versions it no longer requires a reboot).
Now... not many are buying home PCs.
Because most people already have a good desktop or laptop PC at home. PCs do not change as much as they used to, so you do not need to buy a new one (or even upgrade your current one) every year like you used to (unless you play games and really want to have as high FPS as possible). A PC now lasts for many years for common tasks like web browsing.
On the other hand, tablets and phones change a lot, while the hardware may not change as much (or rather, as noticeably), you cannot most of the time upgrade to a newer software version on your old device (like you can upgrade Windows Vista to 7 for example).
Of all people I personally know, the majority have a PC at home (those that don't are usually older than 70 years - didn't need or use a PC all their lives, do not care to start now). Sure, some also have tablets or smartphones.
The measurement of sales for something that most people already have is weird for me. Sure, you can measure sales of some new technology or limited-use things to see how they are doing, but to say that, for example, radio is dead because people are not buying new radios as much as they used to even though most people have a radio and use it (at least in the car) is a bit wrong. Most people already have a radio, a TV and a PC at home, just because sales are dropping may not indicate that the technology is dying, it may be that the devices people already have are still good enough.
Lithuania. Haven't heard of this happening here. However, in some cases, both drivers can be declared guilty. If the insurance company tries to say that the driver in front stopped for no reason to get insurance money, this still does not excuse the driver behind of not keeping a safe distance (well, what if the driver in front had a reason to brake?).
In my country if you hit a car in front of you, you are guilty for the accident because you failed to keep at a safe distance. It does not matter if the driver in front stepped on the brakes for no reason (in some cases you may be both declared guilty). The reasoning is that even if he stepped on the brakes for no reason at that time, what if there was a reason (pothole, someone on the road etc) that you could not see? You would still have hit the car in front of you.
In my country, speed cameras are preceded with a sign announcing the presence of said camera. The signs far enough away that you can slow down without hitting the brakes too hard (unless you were really speeding). The government said that, yes, more fines would be collected without those signs, however, the intended result is not to collect fines, but to make people drive slow, at least in that area. Which the signs do well.
Well, one man in my country had 0.84% BAC. Yea, twice the LD50 level. He was driving but could not find his way out of an (almost) empty parking lot and a bystander called the police.
The record BAC was 1.4%, though that guy was unconscious on the side of a road.
Yea, in my country hitting a car from behind makes you guilty (should have kept the distance), unless the other driver is drunk (drunk driver is always guilty) or he changed lanes too close in front of you and braked immediately.
your outgoing traffic will still be fine
That may not be fine as well, since unless IPv6 can cram both host IPs into the packet, existing sessions will get dropped (which may not happen with IPv4, since IPs stay the same). Also, that requires more complex firewall configuration (what's the probability that one of the IPs will not be entered?).
My back-of-a-napkin solution to this a few years ago was that there's an obvious business model for a few ISP to conspire to jointly provide dual-homing.
There are a few problems with this:
1. The ISPs must be willing to cooperate (unlike now, they only have to provide BGP access).
2. The customer still cannot change ISPs (now I can take my AS to another ISP if I do not like the current one or another pair of ISPs if I'm moving and the current ISPs do not provide service in the new location).
3. The failure of an ISP must trigger a BGP announce to stop traffic from coming to it. This may not happen. Currently we had multiple problems where the main ISP failed but did not announce that - out BGP router still though that the ISP is good. I had to write a script that checks if the internet is accessible and if not (for a few minutes) forces our BGP router to use the other ISP (done with prepends and priorities).
It's so great that all dangerous diseases are immediately obvious to averyone and the sick person himself. I mean there is no way that you could be sick, but not know that yet and transmit the disease to others. Right?
No, it's not. A NAT router works as a good firewall straight out of the box, you may not even need to configure it other than setting the admin password. Uplink IP is configured using DHCP, the router has its own DHCP server for internal network and no incoming connections are allowed.
I remember quite a few v4 IPs of my own machines, machines of the company I work for and of clients.
Adding all that to a DNS server would be a pain (either having one private server with all of them or adding to the servers of the appropriate client, assuming the client has a DNS server, some don't, after all a network of x Windows PCs and a single samba server does not really need DNS, especially if the network is just a bunch of Windows PCs with no server).
When a program does not work, I just run tcpdump (on both ends) and figure out the problem. A port scanner may only be able to scan a limited number of hosts at once, so if it spends a couple of hours trying to scan me, it won't scan others. Also, if the scanning is not automated (like a bot or virus) but is instead because somebody ran nmap, they might get bored and stop.
This is especially useful if the server does not have publicly accessible resources (that is, all incoming connections are limited by source IP). Dropping packets makes it look like that host isn't even there. Also useful in case of a DOS (that is not enough to completely saturate the uplink) as there are no packets going back.