Moxa Technologies AirWorks AWK-1137C Series User Manual page 39

AirWorks AWK-1137C UM
When Turbo Roaming is enabled, the following parameters will be shown:
• Roaming threshold: Determines when to start looking for new AP candidates. If the current connection
quality (SNR or Signal Strength) is lower than the specified threshold, the AWK will start background
scanning and look for next-hop candidates.
NOTE While the AWK device is performing background scanning, the wireless performance will be reduced by 1/3 of
its normal performance.
• Roaming difference: Determines if roaming should be executed. After background scan has been
triggered, the roaming will only occur if the AP candidate(s) provide a better connection quality (based on
the roaming difference value) than the current connection. If multiple access points fulfill the criteria, the
AWK device will pick the best one to roam to.
• Scan channels: Pre-define communication and roaming channels.
• AP alive check: Allows AeroLink Protection to react faster to WLAN disconnections.
NOTE Enabling this feature causes the AWK-1137C to send out packets every 10 ms when there is no traffic to check
if the connection is alive. The high transmission frequency of small alive check packets could potentially affect
your other wireless communications that use the same channel, so only enable this feature when you have full
control of the designated radio channel.
• AP candidate threshold: After the "AP alive check" declares the current access point is no long available,
the surrounding access points must have good enough connection qualities (SNR/Signal Strength) in order
to be the qualified as AP candidates for association.
NOTE The Turbo Roaming recovery time (<150 ms) listed in the product documentation is an average of test results
documented, in optimized conditions, across APs configured with interference-free 20-MHz RF channels,
WPA2-PSK security, and default Turbo Roaming parameters. The clients are configured with 3-channel roaming
at 100 Kbps traffic load. However, a combination of factors affect the AP handover recovery time of a roaming
client, including but not limited to the following:
• On-site RF interference
• Velocity of the moving client devices
• Application traffic throughput
• Turbo Roaming parameters configured. i.e., Roaming threshold, Roaming difference, and AP candidate
threshold.
Therefore, a site survey prior to device deployment is recommended to evaluate the ideal parameter settings
on both clients and APs so that you can come up with an optimal deployment plan for your applications.
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Web Console Configuration