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# MadWifi configuration
config MADWIFI_DEBUG
bool "Enable compilation of debugging features"
depends on EXPERIMENTAL
default n
endchoice
choice
prompt "Rate control algorithm selection"
default MADWIFI_RCA_MINSTREL
help
This option controls how MadWifi chooses its bitrate.
config MADWIFI_RCA_MINSTREL
bool "Use the Minstrel rate control algorithm"
help
This code is takes a wandering minstrel approach. Wander around the
different rates, singing wherever you can. And then, look at the
performance, and make a choice. Note that the wandering minstrel will
always wander in directions where he/she feels he/she will get paid
the best for his/her work.
config MADWIFI_RCA_ONOE
bool "Use the Onoe rate control algorithm"
help
Onoe is a credit based RCA where the value of the credit is determined
by the frequency of successful, erroneous and retransmissions
accumulated during a fixed invocation period of 1000 ms. If less than
10% of the packets need to be retransmitted at a particular rate, Onoe
keeps increasing its credit point till the threshold value of 10 is
reached. At this point, the current transmission rate is increased to
the next available higher rate and the process repeated with credit
score of zero. Similar logic holds for deducting the credit score and
moving to a lower bit-rate for failed packet
transmission/retransmission attempts. However, once a bit-rate has
been marked as failure in the previous attempt, Onoe will not attempt
to select that bit-rate until 10 seconds have elapsed since the last
attempt. Due to the manner in which it operates, Onoe is conservative
in rate selection and is less sensitive to individual packet failure.
config MADWIFI_RCA_AMRR
bool "Use the AMRR rate control algorithm"
help
AMRR uses Binary Exponential Backoff (BEB) technique to adapt the
length (threshold) of the sampling period used to change the values of
bit-rate and transmission count parameters. It uses probe packets and
depending on their transmission status adaptively changes the threshold
value. The adaptation mechanism ensures fewer failed
transmission/retransmission and higher throughput by not switching to a
higher rate as specified by the backoff mechanism. In addition to this,
the AMRR employs heuristics to capture the short-term variations of the
channel by judiciously setting the rate and transmission count
parameters.
config MADWIFI_RCA_SAMPLERATE
bool "Use the SampleRate rate control algorithm"
help
SampleRate decides on the transmission bit-rate based on the past
history of performance; it keeps a record of the number of successive
failures, the number of successful transmits and the total transmission
time along with the destination for that bit-rate. Stale samples are
removed based on a EWMA windowing mechanism. If in the sampling
process, no successful acknowledgment is received or the number of
packets sent is multiple of 10 on a specific link, it transmits the
packet with the highest rate which has not failed 4 successive times.
Other than that it transmits packets at the rate which has the lowest
average transmission time.
endchoice
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