RPL, the Routing Standard for the Internet of Things ... Or Is It?

RPL, the IPv6 Routing Protocol for Low-Power and Lossy Networks, is considered the de facto routing protocol for the Internet of Things (IoT). Since its standardization, RPL contributed to the advancement of communications in the world of tiny, embedded, networking devices, by providing, along with other standards, a baseline architecture for IoT. Several years later, we analyze the extent to which RPL lived up to the expectations defined by the IETF requirements, and tie our analysis to current trends, identifying the challenges RPL must face to remain on the forefront of IoT technology.