Instance Property


A service type that specifies the Multipath TCP connection policy for transmitting data over Wi-Fi and cellular interfaces.


var multipathServiceType: URLSessionConfiguration.MultipathServiceType { get set }


Multipath TCP, defined by the IETF in RFC 6824, is an extension to TCP that permits multiple interfaces to transmit a single data stream. This capability allows a seamless handover from Wi-Fi to cellular, aimed at making both interfaces more efficient and improving the user experience.

The multipathServiceType property defines which policy the Multipath TCP stack uses to schedule traffic across Wi-Fi and cellular interfaces. The default value is none, meaning Multipath TCP is disabled. You can also select handover mode, which provides seamless handover between Wi-Fi and cellular.

Multipath TCP requires server support. Resources for Linux-based systems are available at

See Also

Supporting Multipath TCP

enum URLSessionConfiguration.MultipathServiceType

Constants that specify the type of service that Multipath TCP uses.


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