m-DIBCR: MAC protocol with multiple-step distributed in-band channel reservation

A new medium access control (MAC) protocol to handle packet collisions is proposed. Different from traditional MAC protocols, where only one-step reservation is considered, we propose a multiple-step distributed in-band channel reservation, called m-DIBCR, where m represents the number of steps we consider in the channel reservation. In the protocol, each node maintains m timers, each of which serves as the backoff timer for one of the next m packets to be sent. A node broadcasts the initial values of these timers by piggybacking them in the data packet, and simultaneous transmissions can be avoided when its neighboring nodes overhear these values. Extensive simulations show that, compared with one-step channel reservation, throughput can be dramatically improved by multiple-step channel reservation, especially in networks with high transmission error probabilities and/or a large number of contending nodes.