LiTE4DCB: A Lightweight Throughput Estimation for Heterogeneous Dynamic Channel Bonding WLANs Based on Continuous-Time Markov Chain

Dynamic Channel Bonding (DCB) is a channel access scheme of Channel Bonding (CB) in IEEE 802.11n/ac Wireless Local Area Network (WLAN) that allows devices to dynamically combine a 20 MHz channel with adjacent channels to increase the bandwidth for data transmission. Although numerous studies have explored the throughput analysis of WLAN using DCB (DCB-WLANs) with high accuracy, a research gap still exists, as these works tend to disregard practical considerations, such as backward compatibility and computation time. In response to this gap, in this paper, a lightweight throughput estimation algorithm is studied for heterogeneous DCB-WLANs with the coexistence of legacy nodes (operating only on a single channel) and bonding-able nodes (supporting 802.11n/ac) under various traffic load demands. In particular, by analyzing the airtime occupancy ratio between nodes through Continuous-Time Markov Chain (CTMC)-based modeling, the LiTE4DCB algorithm was proposed to estimate the throughput of the nodes at a low computational cost. For the evaluation, LiTE4DCB was compared with the existing numerical solving method of the CTMC model (NS-CTMC) in terms of estimation accuracy and computation time. The experiment results showed that LiTE4DCB can achieve close throughput estimations with NS-CTMC but requires less computational time. With an increasing number of nodes, LiTE4DCB required negligible additional time, whereas the time needed for NS-CTMC increased exponentially.