  Dynamic Channel Bonding (DCB) allows for the dynamic selection and use of
multiple contiguous basic channels in Wireless Local Area Networks (WLANs). A
WLAN operating under DCB can enjoy a larger bandwidth, when available, and
therefore achieve a higher throughput. However, the use of larger bandwidths
also increases the contention with adjacent WLANs, which can result in longer
delays in accessing the channel and consequently, a lower throughput. In this
paper, a scenario consisting of multiple WLANs using DCB and operating within
carrier-sensing range of one another is considered. An analytical framework for
evaluating the performance of such networks is presented. The analysis is
carried out using a Markov chain model that characterizes the interactions
between adjacent WLANs with overlapping channels. An algorithm is proposed for
systematically constructing the Markov chain corresponding to any given
scenario. The analytical model is then used to highlight and explain the key
properties that differentiate DCB networks of WLANs from those operating on a
single shared channel. Furthermore, the analysis is applied to networks of IEEE
802.11ac WLANs operating under DCB--which do not fully comply with some of the
simplifying assumptions in our analysis--to show that the analytical model can
give accurate results in more realistic scenarios.
