Wireless Sensor and Actuator Networks (WSANs) will represent a key building block for the future Internet of Things, as a cheap and easily-deployable technology to connect smart devices on a large scale. In WSAN implementation, the Routing Protocol for Low-Power and Lossy Networks (RPL) has a crucial role as the standard IPv6-based routing protocol. The RPL specifications define a basic set of security features based on cryptography. Without these features, RPL would be vulnerable to simple yet disruptive routing attacks based on forgery of routing control messages. However, the impact of these features on the performances of the WSAN has not been investigated yet. The contribution of this paper is twofold: an implementation of the RPL security features for the Contiki operating system, which is, at the best of authors’ knowledge, the first available, and an evaluation of their impact on the WSAN performances by means of simulations. We show that the protection against eavesdropping and forgery attacks has a modest impact on the performances, whereas the protection against replay attacks has a more considerable impact, especially on the network formation time which increases noticeably.
Keywords: Internet of Things, Embedded Systems, Secure Routing, RPL