IEEE 802.11ac supports Dynamic Bandwidth Channel Access (DBCA), where a wireless station dynamically selects the channel bandwidth based on the availability of the secondary channels. Although DBCA reduces the possibility of starvation due to non-availability of secondary channels, however, to the best of our knowledge, no existing works look into the performance benefits of IEEE 802.11ac DBCA based on theoretical modeling. In this paper, we develop a two dimensional Markov chain approach to model the performance of DBCA under various channel bonding conditions. We validate the proposed model based on a real testbed implementation. From the thorough analysis of the numerical results obtained from the model, we show that although DBCA improves channel utilization for secondary channels, it requires proper channel allocations and bonding level distributions across the wireless channels for reducing unfairness in the network. We observe that under certain circumstances, the secondary channel users can affect the throughput of primary channel users, which may introduce a short-term unfairness and a significant performance drop in the network.

BibTeX Citation

  author    = {Saketh Mahankali and
               Siva Kesava Reddy K. and
               Raja Karmakar and
               Samiran Chattopadhyay and
               Sandip Chakraborty},
  title     = {{IEEE} 802.11ac {DBCA:} {A} Tug of War between Channel Utilization
               and Fairness},
  booktitle = {2017 {IEEE} Global Communications Conference, {GLOBECOM} 2017, Singapore,
               December 4-8, 2017},
  pages     = {1--6},
  publisher = {{IEEE}},
  year      = {2017},
  url       = {https://doi.org/10.1109/GLOCOM.2017.8254448},
  doi       = {10.1109/GLOCOM.2017.8254448},
  timestamp = {Wed, 16 Oct 2019 14:14:51 +0200},
  biburl    = {https://dblp.org/rec/conf/globecom/MahankaliKKCC17.bib},
  bibsource = {dblp computer science bibliography, https://dblp.org}