curl/docs/cmdline-opts/mptcp.md

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c: Copyright (C) Dorian Craps, dorian.craps@student.vinci.be SPDX-License-Identifier: curl Long: mptcp Added: 8.9.0 Help: Enable Multipath TCP Category: connection Multi: boolean See-also:

• tcp-fastopen Example:
• --mptcp $URL ---

--mptcp

Enables the use of Multipath TCP (MPTCP) for connections. MPTCP is an extension to the standard TCP that allows multiple TCP streams over different network paths between the same source and destination. This can enhance bandwidth and improve reliability by using multiple paths simultaneously.

MPTCP is beneficial in networks where multiple paths exist between clients and servers, such as mobile networks where a device may switch between WiFi and cellular data or in wired networks with multiple Internet Service Providers.

This option is currently only supported on Linux starting from kernel 5.6. Only TCP connections are modified, hence this option does not effect HTTP/3 (QUIC) or UDP connections.

The server curl connects to must also support MPTCP. If not, the connection seamlessly falls back to TCP.