I have a Dell Latitude D800 (Pentium M 1.4 GHz). I can get a solid five hours out of it if the screen brightness is down and the processor isn't too heavily loaded.
It's a welcome jump from many other notebooks where the battery could be more accurately labeled "UPS"...
It works! The usefulness is that I can send the four packets WITHOUT error correction to ensure that they actually arrived. The listener doesn't have to say: "Whoops, I missed packet 2, please resend it", it just has to keep listening. Packets 1, 3, and 4 are sufficient to reconstruct the original message.
If the listener successfully received packets 1,2 and 3, it would signal the sender to stop. Packet 4 wouldn't be needed.
The point is that the communication back and forth to resend missing packets takes time and adds latency. This scheme (obviously extended to more than 3 packets) allows the sender to keep sending at full speed, and to not worry about dropped packets. The receiver just listens until it receives the expected number of packets, and no matter which packets were dropped (whether it received 123, 134, 234, or 124) it can reconstruct the entire message!
It is tremendously useful in improving throughput, esp. on connections will large latency. For example, if I were communicating with Mars, I wouldn't want to have to go back and say: "Please resend packet #434" as it would add a 6 minute latency!! I can just keep listening for ONE extra packet, and I will have the entire message.
Here is a simple example that works the way the article describes. Suppose the original data can be broken into 3 equal length packets A, B, and C.
Send the following 4 packets (where # represents XOR):
A#B
B#C
C
A
Note that ANY three of the four packets can be used to recontruct A, B and C! You just have to XOR them appropriately. It is a bit like solving a linear equation. I haven't tried to extend it to more packets, but I will fiddle with it more tonight.
If you look closely at the diagram and article, it does NOT allow you to see objects hidden inside a container. It can see only completely uncovered objects placed in a special, light-sensitive sphere with a hole to let light in. So much for "objects sealed in closed containers"...
I'm surprised that the fourth book in particular would win a Hugo. In comparison to the third book, it was full of plot holes and tended to meander a bit. It does feel a bit bloated as a book, which she herself admits.
--- BEGIN SPOILER WARNING ---
1) there is the problem with the order of people coming out of the wand (a well-publicized flaw)
2) Prof. "Moody's" assisting of Harry Potter in the first two challenges makes no sense, as they have no bearing on whether he will be the first to touch the cup in the third challenge (only on whether he will win in overall points, which is irrelevant to his purpose)
3) Voldemort's plan is unnecessarily complex. Why not portkey a brick and get Harry to touch that?
Slashdot Mirror
> Iran, on the other hand, has repeatedly declared it's desire for the total annihilation of the the nation of Israel (among others).
Well, no, actually. He did call for the regime to fall, a much different meaning. Did Iran threaten Israel with nuclear attack? No.
On the other hand, we had a U.S. presidential candidate singing "Let's Bomb Iran". Why the double standard?
> demonstrated intent to export insurrection with the stated goal of complete domination
Source? (other than Fox News, of course)
I have a Dell Latitude D800 (Pentium M 1.4 GHz). I can get a solid five hours out of it if the screen brightness is down and the processor isn't too heavily loaded.
It's a welcome jump from many other notebooks where the battery could be more accurately labeled "UPS"...
If the listener successfully received packets 1,2 and 3, it would signal the sender to stop. Packet 4 wouldn't be needed.
The point is that the communication back and forth to resend missing packets takes time and adds latency. This scheme (obviously extended to more than 3 packets) allows the sender to keep sending at full speed, and to not worry about dropped packets. The receiver just listens until it receives the expected number of packets, and no matter which packets were dropped (whether it received 123, 134, 234, or 124) it can reconstruct the entire message!
It is tremendously useful in improving throughput, esp. on connections will large latency. For example, if I were communicating with Mars, I wouldn't want to have to go back and say: "Please resend packet #434" as it would add a 6 minute latency!! I can just keep listening for ONE extra packet, and I will have the entire message.
I hope that clears up my example above.
Send the following 4 packets (where # represents XOR):
A#B
B#C
C
A
Note that ANY three of the four packets can be used to recontruct A, B and C! You just have to XOR them appropriately. It is a bit like solving a linear equation. I haven't tried to extend it to more packets, but I will fiddle with it more tonight.
Alas, it was too cool to be true.
--- BEGIN SPOILER WARNING ---
1) there is the problem with the order of people coming out of the wand (a well-publicized flaw)
2) Prof. "Moody's" assisting of Harry Potter in the first two challenges makes no sense, as they have no bearing on whether he will be the first to touch the cup in the third challenge (only on whether he will win in overall points, which is irrelevant to his purpose)
3) Voldemort's plan is unnecessarily complex. Why not portkey a brick and get Harry to touch that?
--- END SPOILER WARNING ---