In recent years, the growth of WLANs (Wireless
Local Area Networks) is very high and it has become the
common means of access to the internet. The proliferation of
Wi-Fi based WLANs/Wi-Fi hotspots in public places
enables ubiquitous internet access. The public places are
referred to as large audience environments, in which each
Wi-Fi access point (AP) normally serves a crowd of mobile
stations (STAs) simultaneously. The performance of those
Wi-Fi hotspots is extremely poor in terms of low throughput
and severe delay. After carefully investigating the traffic
characteristics in Wi-Fi hotspots the studies shows that the
main causes of such poor performance are media access
control (MAC) inefficiency and downlink-uplink traffic
asymmetry. To cope with these issues, the key idea is
pooling, which facilitates, an access point (AP) to pool
frames for multiple STAs in a single transmission. It
reduces contention overhead in downlink transmission and
conveys more frames in each channel access. As such, each
downlink transmission carries more payloads for multiple
receivers, it enables in time response for multiple STAs
concurrently in a single transmission and thus improves
MAC efficiency and solves traffic asymmetry
simultaneously.
Anjaly Kurian : completed her B.Tech in Electronics and
Communication Engineering under Mahatma Gandhi
University,Kerala. Presently she is pursuing M.Tech in Electronics
with specialization in Wireless Technology under Cochin University
of Science and Technology (CUSAT),Kerala.
Gnana Sheela K : received her Ph.D in Electronics and
Communication from Anna University, Chennai. She is working as a
Professor, Department of ECE, Toc H Institute of Science and
Technology. She has published more than 40 international journal
papers. She is reviewer, editor and evaluator in various international
papers. Also she is life member of ISTE.
MAC Efficiency
Frame Aggregation
Contention
Reduction
Pooling
Wi-Fi
IEEE 802.11
WLAN
In this paper, we investigated the characteristics of
Wi-Fi traffic in large audience environments and found
that pooling is a promising approach to scale the
performance of Wi-Fi in crowded public places. We
observe that by enabling frame pooling for multiple STAs
in the downlink transmission, the main causes of poor
Wi-Fi performance in large audience environments can be addressed simultaneously. T he proposed pooling
design facilitates a new dimension to improve the
efficiency of public Wi-Fi networks. Pooling is built on
the heels of a lightweight frame structure in the existing
Wi-Fi standards as an optional mechanism that is enabled
in large audience environments to ease heavy contention.
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Transactions on Mobile Computing, DOI
10.1109/TMC.2015.244929.
