  Seamless redundancy can be profitably exploited to improve predictability of
wireless networks in general and, in particular, IEEE 802.11. According to this
approach, packets are transmitted by senders on two (or more) channels at the
same time and duplicate copies are discarded by receivers. As long as the
behavior of physical channels is uncorrelated, communication quality improves
noticeably, in terms of both transmission latencies and percentage of dropped
frames. In this paper, communication over redundant links has been analyzed by
means of a thorough experimental campaign, based on measurements carried out on
real devices. Results confirm that, under typical operating conditions, the
assumption of independence among channels in properly designed systems is
verified reasonably well. Indeed, in our experiments, measured link quality
indices did not differ more than 10% from what we expected from theory. This
grants for redundant solutions tangible advantages over conventional Wi-Fi
networks.
