RPL-RP: RPL with Route Projection for Transversal Routing

Routing Protocol for Low-Power and Lossy Networks (RPL) as the most widely used routing protocol for constrained Internet of Things (IoT) devices optimizes the number of routing states that nodes maintain to minimize resource consumption. Given that the routes are optimized for data collection, this leads to selecting sub-optimal routes, particularly in case of east-west or ”transversal” traffic. Additionally, RPL neglects interactions with a central entity in the network for monitoring or managing routes and enabling more flexibility and responsiveness to the system.In this paper, we present RPL with Route Projection (RPL-RP) that enables collecting siblings’ relations at the root node in order to inject routing states to the routers. This backward-compatible RPL extension still favors collection-based traffic patterns but it enriches the way routing protocol handles other flow directions. We address different advantages of RPL-RP in contrast to standard RPL and evaluate its overhead and improvements in terms of end-to-end delay, control overhead and packet delivery ratio. Overall, RPL-RP halves the end-to-end delay and increases network reliability by 5% while increasing network overhead by only 3%.