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Comment by BillFranklin | Hacker News Reader

If you're interested in recent state-of-art improvements to TCP congestion control, check out the Remy project, it's pretty amazing https://web.mit.edu/remy/.

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> But there is a closely-related question, which is to ask: how much does Remy depend on the way the simulator works? Will it work on real networks? We have some confidence that the results don't depend on fine details of the simulator, because RemyCCs are optimized within Remy's own simulator but evaluated inside ns-2 and its TCP implementations, which were developed independently and long predate Remy. But the only way to know for sure is to try it on a real network, which we haven't done yet.

Did they try it on a real network?

Also, it seems unclear that using a Remy congestion control algorithm while all the machines around you are using Cubic will help very much.

I’m not sure if much more research has been done here from this team. I was able to produce similar results in my dissertation, also not in a production setting.

Regarding your second point, the way congestion avoidance algorithms typically work is to punish the local client for the state of the global congestion. If Remy can do that in a more efficient way (ie greater throughput or fairness for the local client) then it would be beneficial to use the algorithm before others switch.

The page mentions Ubuntu 13.04 and doesn't mention BBR, is the project still active ?

Out of curiosity, what do modern OSes use?

Cubic, or bbr I’ve seen in practice. Bbr is extremely efficient in particular ( and I’d like to know how Rémy compares to it )

Edit: bbr essentially builds and fits a model - in some ways it’s learning ( it’s stats essentially).

cubic and bbr

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