Several motivations and one main objective
Multi-Path Transmission Control Protocol

The widespread use of multi-interface terminals opens up interesting prospects for users: the ability to aggregate several links associated with the different interfaces available means substantial gains in bandwidth, to the benefit of communication quality (downloading a video file, for example). Similarly, the ability to maintain an active session, while dynamically selecting the access network that offers the best guarantees in terms of availability or robustness at a given moment, or that offers the best pricing conditions (for example, switching to the home WLAN infrastructure when the user returns home), is likely to significantly improve the level of connectivity service quality as perceived by the user.

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