Issue No. 03 - March (2013 vol. 12)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TMC.2012.18
I. Pefkianakis , Dept. of Comput. Sci., Univ. of California, Los Angeles, Los Angeles, CA, USA
S. H. Y. Wong , IBM Res., Hawthorne, NY, USA
Hao Yang , Nokia Res. Center, San Jose, CA, USA
Suk-Bok Lee , Dept. of Comput. Sci., Univ. of California, Los Angeles, Los Angeles, CA, USA
Songwu Lu , Dept. of Comput. Sci., Univ. of California, Los Angeles, Los Angeles, CA, USA
Rate adaptation is a mechanism unspecified by the IEEE 802.11 standards, yet critical to the system performance by exploiting the multirate capability at the physical layer. In this paper, we conduct a systematic experimental study on rate adaptation over 802.11 wireless networks. Our key contributions are as follows: First, we present a critique on popular design guidelines adopted by many practical algorithms and we uncover their limitations. Our study reveals that these seemingly correct guidelines can be misleading in practice, thus incurring significant performance penalty in certain scenarios. Second, we study the short-term channel dynamics and explore how they guide rate adaptation. To this end, we design and implement a new History-Aware Robust Rate Adaptation Algorithm (HA-RRAA). HA-RRAA uses short-term loss ratio to opportunistically guide its rate change decisions, a cost-effective adaptive RTS filter to prevent collision losses from triggering rate decrease and an adaptive time window to limit transmissions at high loss rates. Our extensive experiments show that HA-RRAA outperforms popular algorithms in all tested scenarios, with goodput gains up to 51.9 percent in field trials.
wireless LAN, adaptive filters, filtering theory, radio networks, wireless channels, adaptive time window, history-aware robust 802.11 rate adaptation, IEEE 802.11 standards, system performance, multirate capability, physical layer, 802.11 wireless networks, performance penalty, short-term channel dynamics, history-aware robust rate adaptation algorithm, HA-RRAA, short-term loss ratio, rate change decisions, cost-effective adaptive RTS filter, collision losses, triggering rate decrease, Signal to noise ratio, Propagation losses, Probes, Algorithm design and analysis, IEEE 802.11 Standards, Guidelines, Channel estimation, performance, Rate adaptation, 802.11, design, experimentation
Hao Yang, S. H. Wong, I. Pefkianakis, Suk-Bok Lee and Songwu Lu, "Toward History-Aware Robust 802.11 Rate Adaptation," in IEEE Transactions on Mobile Computing, vol. 12, no. , pp. 502-515, 2013.