Alternative Parent Selection for Multi-Path RPL Networks

International audienceThe IPv6 Routing Protocol for Low-Power and Lossy Networks (RPL) is designed for Internet of Things (IoT) applications. This Low Power and Lossy Network (LLN) protocol builds a Destination Oriented Directed Acyclic Graph (DODAG) network by transmitting DODAG Information Object (DIO) control packets. The DODAG structure created is hierarchical, where the upward routes are towards nodes with a lower rank, with the sink/root node having the lowest rank. To achieve connectivity, RPL nodes select their routes through an Objective Function (OF). To improve reliability and minimize jitter, we implemented Packet Replication and Elimination (PRE) and a multi-path routing OF. However, no standardized algorithm exists for this purpose although for PRE, several algorithms have been proposed for selecting an Alternative Parent (AP) node. An example of this is the LeapFrog Collaboration (LFC) algorithm, which selects an AP using a triangular pattern. In this paper, we examine how this selection affects power, network overload, delay and jitter. We focus on analyzing the selection of an AP, in terms of how strict the selection should be when a triangular pattern is used and what trade-offs are presented between network traffic and reliability