[Bloat] sweet tcp

[Jaume Barcelo <jaume.barcelo@upf.edu>]

Hi,

I was explaining the bufferbloat problem to some undergrad students
showing them the "Bufferbloat: Dark Buffers in the Internet" paper. I
asked them to find a solution for the problem and someone pointed at
Fig. 1 and said "That's easy. All you have to do is to operate in the
sweet point where the throughput is maximum and the delay is minimum".

It seemed to me that it was a good idea and I tried to think a way to
force TCP to operate close to the optimal point. The goal is to
increase the congestion window until it is larger than the optimal
one. At that point, start decreasing the congestion window until is
lower than the optimal point.

To be more specific, TCP would be at any time increasing or decreasing
the congestion window. In other words, it will be moving in one
direction (right or left) along the x axis of Fig. 1 of Getty's paper.
Each RTT, the performance is measured in terms of delay and
throughput. If there is a performance improvement, we keep moving in
the same direction. If there is a performance loss, we change the
direction.

I tried to explain the algorithm here:
https://github.com/jbarcelo/sweet-tcp-paper/blob/master/document.pdf?raw=true

I am not an expert on TCP, so I decided to share it with this list to
get some expert opinions.

Thanks,
Jaume