ScienceDaily (Sep. 24, 2010) — http://www.sciencedaily.com/releases/2010/09/100923142448.htm
Pentagon Study Excerpts: "When there are no delays, the more you communicate with your neighbor, the better global performance becomes," …
"Understanding the impact of delays can enable network operators to know when less communication effort can … be more efficient for overall performance." …
"If there are delays, for a while performance will increase, but even if you work harder to better communicate with your neighbors, eventually performance will decrease until it reaches zero. …
“you also need to know when to "shut up," Korniss explained. After a certain period of poor communication, he said, no matter how fast or accurate you attempt to make your future communication, all communication is counterproductive. …
It took me some time to penetrate my thick skull that sending out too much information is contra-productive. If you go to http://jimboguy.blogspot.com , you can read what you want by looking at the blog summaries on the left column monthly.
Jim Kawakami, Sept 24, 2010
Individuals within a networked system coordinate their activities by communicating to each other information such as their position, speed, or intention. At first glance, it seems that more of this communication will increase the harmony and efficiency of the network. However, scientists at Rensselaer Polytechnic Institute have found that this is only true if the communication and its subsequent action are immediate.
Using statistical physics and network science, the researchers were able to find something very fundamental about synchronization and coordination: if there are sustained delays in communication between just two or three parts of a system, performance of the entire system will eventually collapse.
The findings apply to any network system where individuals interact with each other to collectively create a better outcome. This ranges from a flock of birds suddenly dodging to the right in one unified movement to avoid a predator to balancing load in large-scale computer networks to the spread of a rumor throughout an online social network.
The findings were published last month in Physical Review Letters.
Previous studies by the researchers have revealed that the minute interactions between neighboring individuals, referred to as nodes, are the foundation for overall network performance. The fast, accurate, and balanced movement of information between neighboring nodes is what prevents the birds from scattering and allows a story to accurately spread on the Web.
But, as is frequently the case in real-world scenarios, what happens when the information from your neighbor is not up to date? What occurs when there are delays in the transmission or processing of the information between neighbors? The researchers utilized stochastic differential equations, a type of mathematical equation used to model the time evolution of complex systems with random variables, to determine what happens when delays are input into the system. … http://www.sciencedaily.com/releases/2010/09/100923142448.htm
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