Multipath TCP Support - There's a new porting attempt in progress by a University

[ilikenwf]

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Is your feature request related to a problem? Please describe.

For multi wan connection aggregation through a VPS, a multipath TCP feature would be nice.

Describe the solution you like

I realize this may be beating a dead horse, but in the past there have been efforts to add MPTCP support to FreeBSD. Every time this happens it usually is a fork of a prior project. Recently I located another in progress work on MPTCP for FreeBSD 13, based on the prior patches, however it is in active development by a university in Australia, and is funded by a Comcast Grant. I think it may be worth revisiting, but it is a bit beyond my skills as I'm more software oriented and not the best network engineer.

https://github.com/MPTCP-FreeBSD

In addition, another useful resource on this topic is Steve Jacobson's FreeBSD MPTCP information page:

https://xenon.stanford.edu/~sjac/freebsd_mptcp_info.html

Describe alternatives you considered

Right now the only option I have is to setup OpenMPTCP router and use it in between opensense and my wans.

[AdSchellevis]

There's ROUTE_MPATH in FreeBSD since freebsd 13 (https://www.freebsd.org/releases/13.0R/relnotes/), which is disabled by default on our end (net.route.multipath=0). I do expect quite some regressions, but if it does help for your user-case, you could always take a look (https://man.freebsd.org/cgi/man.cgi?route).

Documentation is quite limited as far as I could find, which also makes it less likely we will spend time on it as it might break current routing assumptions in core.

Our experience with a lot of these type of additions is similar to yours I'm afraid, one time efforts without long term commitment leading to bugs nobody cares to look at.

[ilikenwf]

Thank you for the information - I'll look into ROUTE_MPATH.

I suspect this may later become more of a topic of conversation as more and more people migrate to full or partial remote work as time goes on.