Successive-Capture Analysis of RTS/CTS in Ad-Hoc Networks

We consider a wireless ad-hoc network with random ALOHA transmissions between nodes. However nodes can decide to use the Request-to-Send (RTS) / Clear-to-Send (CTS) protocol for occasional long packets. Via the RTS/CTS protocol, nodes proactively make a temporal and spatial reservation of the channel before sending the actual data payload (DATA). The aim of this paper is to explore the effectiveness of the RTS/CTS protocol in such a wireless network, in particular by alleviating the commonly made assumption that an entire RTS/CTS/DATA cycle is always successful if only the RTS packet is recovered. Our results show that this assumption loses its accuracy if the data rate is optimized for the link throughput or if one aims for allowing dense frequency reuse. We quantify the spatial and temporal impact of the RTS/CTS reservation on the network traffic, as well as the link throughput achieved. Numerical results demonstrate that for sufficiently long packets, a significant throughput gain can be achieved by employing the RTS/CTS reservation.