Cambium Networks PMP 450 AP, Configuration Manual

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Chapter 2: Tools Using the Link Status tool
Page
2-365
BER Results This field displays the over-the-air Bit Error Rates for each downlink. (The
ARQ [Automatic Resend Request] ensures that the transport BER [the BER
seen end-to-end through a network] is essentially zero.) The level of
acceptable over-the-air BER varies, based on operating requirements, but a
reasonable value for a good link is a BER of 1e-4 (1 x 10
-4 ) or better,
approximately a packet resend rate of 5%.
BER is generated using unused bits in the downlink. During periods of peak
load, BER data is not updated as often, because the system puts priority on
transport rather than on BER calculation.
Reg Requests A Reg Requests count is the number of times the SM/BHS registered after
the AP/BHM determined that the link had been down.
If the number of sessions is significantly greater than the number for other
SMs/BHS, then this may indicate a link problem (check mounting, alignment,
receive power levels) or an interference problem (conduct a spectrum scan).
ReReg Requests A ReReg Requests count is the number of times the AP/BHM received a
SM/BHS registration request while the AP/BHM considered the link to be still
up (and therefore did not expect registration requests).
If the number of sessions is significantly greater than the number for other
SMs/BHS, then this may indicate a link problem (check mounting, alignment,
receive power levels) or an interference problem (conduct a spectrum scan).