Artificial Collision-Based Dynamic Slot Assignment for In-Band Control Networks

In this paper, we propose a novel dynamic slot-assignment scheme using artificial collisions called artificial collision-based dynamic slot assignment (AC-DSA) for multi-hop networks, which is based on the in-band control mechanism. In-band control-based networks have no exclusively reserved slots for newly arrived nodes; thus, the throughput can be improved compared with that of the out-of-band control-based networks. In in-band control based networks, a newly arrived node can use idle slots to transmit its control packet to request a slot assignment. However, if no idle slots are available, the node cannot transmit its control packet even though it has a higher priority than the existing nodes in the network, because a newly arrived node has to wait until idle slots are available in conventional schemes. To address this issue, AC-DSA uses the duration information of artificial packet collisions as a control message for slot assignment, which enables nodes with high priority to deprive a non-idle slot of nodes with low priority to guarantee quality of service requirements when no idle slots are available. We formulate an analytical model for the proposed slot-assignment scheme and compare it with the conventional one. Further, we demonstrate the feasibility and efficiency of the AC-DSA during high-traffic conditions considering the capture effect.