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MIT Uses Machine Learning Algorithm To Make TCP Twice As Fast
An anonymous reader writes "MIT is claiming they can make the Internet faster if we let computers redesign TCP/IP instead of coding it by hand. They used machine learning to design a version of TCP that's twice the speed and causes half the delay, even with modern bufferbloated networks. They also claim it's more 'fair.' The researchers have put up a lengthy FAQ and source code where they admit they don't know why the system works, only that it goes faster than normal TCP."
We're already in that boat. One of the reasons it's so hard to make changes is that nobody really knows why the internet works. We know how and why individual networks work. We can understand and model RIP and OSPF just fine. And we know how BGP operates too. But that large scale structure is a mess. It's unstable. The techniques we use could easily create disconnected or even weakly connected networks. But they don't except for occasionally a single autonomous system falling off. We've built ourselves a nice big gordian knot already. We know what it's made of, and we know how it operates, but good luck actually describing the thing.
Huh? Did you read the same article as I did? As far as I can tell, the article is about a TCP congestion control algorithm, which runs on both endpoints of the connection, and has nothing to do with QoS on intermediate routers. The algorithm generates a set of rules based on three parameters resulting in a set of actions to take like increasing advertised receive window and tx rate control. The result of which is a vastly improved total network throughput (and lower latency) without changing the network itself.
I fail to see the relevance of predictive/adaptive caching. It isn't even mentioned in the article.
One of the reasons it's so hard to make changes is that nobody really knows why the internet works.
We still don't know how to deal with congestion in the middle of a pure datagram network. The Internet works because last-mile congestion is worse than backbone congestion. If you have a backbone switch today with more traffic coming in than the output links can handle, the switch is unlikely to do anything intelligent about which packets to drop. Fortunately, fiber optic links are cheap enough that the backbone can be over-provisioned.
The problem with this is video over the Internet. Netflix is a third of peak Internet traffic. Netflix plus Youtube is about half of Internet traffic during prime time. This is creating demand for more and more bandwidth to home links. Fortunately the backbone companies are keeping up. Where there's been backbone trouble, it's been more political than technical. It also helps that there are so few big sources. Those sources are handled as special cases. Most of the bandwidth used today is one-to-many. That can be handled. If everybody was making HDTV video calls, we'd have a real problem.
(I was involved with Internet congestion control from 1983-1986, and the big worry was congestion in the middle of the network. The ARPANET backbone links were 56Kb/s. Leased lines typically maxed out at 9600 baud. Backbone congestion was a big deal back then. This is partly why TCP was designed to avoid it at all costs.)
As complex systems goes there are far worse. Go ask an engineer or a scientist.
I am a scientist--specifically, a bioinformaticist, which means I try to build mathematical and computational models of processes in living organisms, which are kind of the canonical example of complex systems. And I will cheerfully admit that the internet, taken as a whole, is at least as complex as anything I deal with.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
We should keep investigating why it works but, to be fair, the history of communications is implementing tech before we understand it (e.g. the first trans-Atlantic cable, implemented before we understood wave-particle duality, and therefore couldn't troubleshoot it well when it broke).
...that's Isaac Newton telling us, "I can explain the effects of gravity but I have no clue WTF it is."
Let's not forget this important quote: "I frame no hypotheses; for whatever is not deduced from the phenomena is to be called a hypothesis; and hypotheses, whether metaphysical or physical, whether of occult qualities or mechanical, have no place in experimental philosophy."
Geeks like to think that they can ignore politics, you can leave politics alone, but politics won't leave you alone.-rms