UC Santa Cruz

This thesis introduces QSMA-CR, a MAC layer protocol that leverages carrier sensing to achieve lower latency than its predecessors: QSMA and ALOHA-QS. QSMA-CR establishes a distributed queue to maintain fairness and achieve high throughput. Each node sends data frames within their reserved slot every queue cycle. After every cycle is a joining period in which unjoined nodes attempt to make a reservation. In QSMA and ALOHA-QS, nodes have latency due to a lack of a contention resolution algorithm that optimizes the join process. QSMA-CR has a global and node-level state, enabling smarter contention resolution that allows high throughput and lower latency. We used a 10-minute experiment with 50 nodes to show that QSMA-CR can achieve lower latency than QSMA achieving similar throughput.