ORPL-DT: Opportunistic Routing for Diverse Traffic patterns

Abstract

ORPL is an extension of RPL (IPv6 Routing Protocol for LLNs) with opportunistic routing, which shows lower latency and less energy consumption than existing tree-based routing protocols such as CTP (Collection Tree Protocol) and RPL by exploiting multipath diversity. We used an indoor testbed to evaluate the performance of conventional ORPL on ContikiOS. Through testbed experiments, we found out that ORPL's EDC (Expected Duty Cycled wakeups) metric is outdated because of lacking upward traffic in a downward-centric traffic scenario. Outdated EDC leads to inaccurate routing set which degrades the overall performance. We propose ORPL-DT that updates each nodes EDC metric using downward traffic to tackle the problem. Performance evaluation on an indoor testbed shows that ORPL-DT improves average PRR (packet reception ratio) for both downlink and uplink. Also it improves fairness as well.