RPL routing for multigateway AMI networks under interference constraints

The IETF is developing an IPv6 Routing Protocol for Low Power and Lossy Networks (RPL) for smart machine-to-machine networks. In this paper, we present a RPL protocol for the mesh based multigateway Advanced Metering Infrastructure (AMI) of the Smart Grid. The multigateway RPL is based on the construction and maintenance of multiple directed acyclic graphs (DAG) that are each rooted at a gateway. The DAGs are constructed using node rank computation. We incorporate an interference based routing metric into the RPL to facilitate rank computation. The interference link metric, based on SINR measurements, is used to construct and maintain DAGs for least interference routing. We will show that our multigateway RPL protocol performs better in terms of packet delivery ratio, delay and throughput when compared to generic routing schemes such as AODV and RPL protocols that use ETX (expected transmission time) as the link metric. We also study the multigateway RPL under link failures to show that high throughput data routing can be achieved.