3Com 3CRWDR200A-75-US - OfficeConnect ADSL Wireless 108 Mbps 11g Firewall Router, User Manual

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Wireless Settings 59
priority, and hence the more capacity share for a given traffic
condition.However, the probability of collisions increases when operating
with smaller CWmin. These parameters can be used in order to
differentiate the channel access among different priority traffic.
EDCA STA Parameters:
Each station maintains a Contention Window (CW), which is used to
select the random back off counter.The BC is determined as a random
integer drawn from a uniform distribution over the interval (0, CW).The
CW size is initially assigned CWmin, and increases when a transmission
fails, i.e., the transmitted data frame has not been acknowledged.After
any unsuccessful transmission attempt, another back off timer is
performed, with an upper bound of CWmax.This reduces the collision
probability in case there are multiple stations attempting to access the
channel.
CW min: should be smaller for delay-sensitive data
CW max: should be smaller for delay-sensitive data
AIFSN: should be smaller for delay-sensitive data
TXOPLimit: These will allow multiple MAC frames consecutively as
long as the whole transmission time does not exceed the TXOP limit.So
keep it larger for delay-sensitive data.
ACM: Admission Mandatory; could be turned on to mandatory
execution of the contention control.
Connection Control You can restrict certain wireless clients from accessing the router by
specifying their MAC address and enabling access restriction.