Say I have 3 networks with 20mbps connections and a server with

Of course I do have 3 seperate network adapters

>>59303122
>Could I possibly chroot into a different environment where the network adapter is specific to that environment?
It's called network namespaces.
You can create a network namespace with "ip netns add NAME". You can "chroot" inside with "ip netns exec [NAME] bash". Somehow you have to attach each network interface to each specific namespace, chroot inside them and set up ip address and maybe routing.

TL;DR: keyword: you want "network namespaces"

For your specific problem I think there is a specific protocol, so you don't have to hack around like this though. I forget its name though.

>>59303122
Ok, I found the protocol you are looking for. It's called MPTCP.

https://www.multipath-tcp.org/

Never used it, AFAIK it needs both server and client support and is implemented for linux. Have fun setting it up. Once set up it should be much more painless than the network namespace hackery.

>>59303677
>>59303746
Interesting, thanks for the help.

>>59303746
Actually I think I'll use network namespaces as it looks very easy to setup: http://blog.scottlowe.org/2013/09/04/introducing-linux-network-namespaces/

Plus the AUR linux-mptcp is using an outdated kernel.

>>59303844
Yeah, go with that. Especially if it's a one-off thing.