Real-world use of Linux multipath TCP LWN
looked at the Linux multipath TCP
implementation back in 2013. That code remains out of tree, but it now
seems that
it is
being used in some Samsung phones in Korea. "
This service
enables smartphone users to reach bandwidth of up to 1 Gbps on existing
smartphones. This is probably the fastest commercially deployed mobile
network. They achieve this high bandwidth by combining both fast LTE (with
carrier aggregation) and fast WiFi networks on Multipath TCP enabled
smartphones."
(Thanks to Oliver Bonaventure).