Shaping the Linux kernel MPTCP implementation towards upstream acceptance
Doru-Cristian Gucea, Octavian Purdila · 2015
This paper describes the challenges that we face in trying to integrate MultiPath TCP (MPTCP) in the official Linux kernel repository. This is a non-trivial task because the MPTCP implementation is invasive and mixes the MPTCP and TCP code and thus substantially increases the complexity of Linux's kernel TCP/IP implementation. In this paper we present several changes done to the MPTCP implementation that move the MPTCP code in a separate layer with the purpose of managing the complexity of the kernel implementation. To do so a series of problems must be solved: extract the MPTCP specific code from the TCP hotpath, create an MPTCP specific layer on top of TCP, pass MPTCP specific options to/from the TCP layer and have an efficient TCP fallback mechanism.