Multipath DTLS : design and implementation

The goal of this master's thesis is to propose an extension for Datagram Transport Layer Security (DTLS) which is a protocol to communicate securely over an unreliable channel. Our extension, called Multipath DTLS, enables a DTLS session to use interfaces concurrently. This feature becomes more useful with the emergence of devices with 2 interfaces or more (for instance LAN, Wi-Fi, 4G...). Smartphones, tablets and even notebooks are all good candidates for multipath protocols. The ability to connect or disconnect interfaces on the fly and seamlessly for the application was a dream becoming now reality. Unlike other existing multipath protocols, the data security is a major objective and the design has been elaborated to keep the same security level as normal DTLS sessions. We review the current state of the art by presenting DTLS in detail but also MPRTP. With some concepts borrowed from the latter, we present our design for Multipath DTLS, detailing all the modifications brought to the former protocol. In addition, we have implemented our extension inside an existing DTLS library and we disclose here some promising results. This proposal might be used by a large amount of applications in very different contexts and on a substantial variety of devices.