The migration of railway signaling systems based on circuit switching toward Internet protocol (IP) is on the way. Consequently, new strategies to promote reliability in packet-?switching networks must be studied. In this article, we propose the use of multipath technology to enhance the availability and reliability of these communications. To our knowledge, this is the first time that multipath strategies are customized for the railway train-control domain. We present the basic requirements that a multipath protocol must fulfill to increase the reliability and evaluate different related multipath proposals and provide our own customized protocol, the reliable multipath transmission control protocol (RMPTCP). Finally, we demonstrate the availability improvement that our proposed multipath strategy introduces.

With the development of the 6LoWPAN standard, sensors can be natively integrated into the IP world, becoming tiny information providers that are directly addressable by any Internet-connected party. To protect the information gathered by sensors from any potential attacker on the Internet, it is essential to have trustworthy real-time information about the legitimacy of every attempt to interact with a sensor. Our approach to address this issue is Ladon, a new security protocol specifically tailored to the characteristics of low capacity devices. In this paper, we study the performance of Ladon, showing that it successfully meets the requirements of the targeted environments. To that end, we evaluate the delay and energy consumption of the execution of Ladon. The obtained results show that the cost of Ladon is bounded, even in situations of high packet loss rates (20–80%) and comparable to that of other protocols that implement fewer security features.