Comment doable w/deep understanding of TCP (Score 1) 174
Ignorant troll remarks notwithstanding, this idea is sensible and doable, but requires deep understanding of TCP: e.g. yes it is supposed to be robust to duplicated or misordered packets, but no it will not perform acceptably with even low incidence rates of either. Symmetric PEPs w/explicit multipath packet processing will be needed: the Windows client is not a good candidate for one end of that pair; a lightweight Linux based transparent gateway, using e.g. tun/tap and netfilter, with some coding, can do it. We have been doing similar things for disadvantaged mobile wireless platforms (e.g. aircraft in flight) for years. Beware: transport mode IPSEC, if running between the ultimate client & server, makes it much more difficult (requiring guesstimates of what is happening with opaque transport layer headers). With an IP tunnel over a Type II Hybrid ARQ/FEC transport over packet by packet concurrent multipath routing, you can accomplish the OP's goal & more, but overhead is more than 100% unless you have 3 or more paths.