Multipath TCP for Linux

Multipath TCP (MPTCP) builds on top of TCP to improve connection redundancy and performance by sharing a network data stream across multiple underlying TCP sessions. The MPTCP v1 protocol is defined in RFC 8684.

The Linux MPTCP community develops and maintains the MPTCP v1 stack in the Linux kernel (v5.6 or later) and associated userspace tools and libraries.

This site is new and still evolving, so please refer to the Linux MPTCP Upstream Project wiki for additional information.

For out-of-tree kernels before v5.6 and an implementation of the experimental MPTCP v0 protocol, see


As of Linux v5.19, major features of MPTCP include:

See the ChangeLog for more details.



Kernel Development