Exploring the Tradeoff between Performance and Overhead of the Relay Selection Mechanism in the Uniform Stress Routing Protocol

The constrained nature of Low power and Lossy Networks (LLNs) inevitably impacts fundamental networking tasks. The focus of our work is routing protocols, where the constraints of the network discourage the maintenance of large routing tables and the use of excessive control traffic, nonetheless optimizing for metrics such as delay and packet loss. In a previous work, we briefly introduced the Uniform Stress Routing protocol (USR), an approach inspired from the load distribution in trees. USR selects a limited set of relays at every node for all traffic forwarding, based on their ability to deliver traffic to the most solicited destinations, thus traffic directed to least solicited destinations will take suboptimal paths. This paper aims at further clarifying the concept of USR, then putting its performance to the test on Network Simulator 3. Experiments were conducted using the LR-WPAN module, and showed that USR allows a 13% decrease in control traffic, with no effect on the packet loss, but an increase in delays of 20%.