ZyXEL Communications NXC-8160, User Manual

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Chapter 4 WLAN Settings
NXC-8160 User’s Guide
58
Figure 23 WLAN > ESSID Definition > WMM
The following table describes the labels in this screen.
Table 19 WLAN > ESSID Definition > WMM
LABEL DESCRIPTION
SSID
Choose ESSID Select an ESSID for which to configure the NXC-8160’s WMM parameters.
WMM Parameters
ACK Policy Select whether to enable the NXC-8160 sends acknowledgement packets for
each data packet received in each of the four WMM parameters:
Background , Best Effort , Video , and Voice .
Sending an acknowledgement packet increases the reliability of data
transmission as it lets the origination point know that the data was received
intact and that it can transmit the subsequent packet, but doing so also
increases the NXC-8160’s bandwidth usage.
For some data types, packet loss may not be an issue (such as with video
streaming, where missing packets are compensated for by using keyframes
and other types of digital presdigitation to “smooth over” the missing bits). In
such cases, leaving the
ACK Policy check box unticked will have minimal
deleterious side effects on the data packets’ Quality of Service.
CWmin This indicates the current value of the Minimum Contention Window for the
given WMM parameter. This is the minimum number of milliseconds that the
NXC-8160 waits for an incoming data packet before sending a retry signal.
Each time a retry signal is sent, the CWmin value doubles in duration until the
CWmax value is reached.
CWmax This indicates the current value of the Maximum Contention Window for the
given WMM parameter. This is the maximum number of milliseconds that the
NXC-8160 waits for an incoming data packet before sending a retry signal.
The NXC-8160 continues to send a retry signal until the maximum number of
retries allowed is reached.
AIFSN This indicates the current value of the Arbitration Inter-Frame Spacing
Number for the given parameter. This is the number of milliseconds that the
NXC-8160 waits between receiving data packets.
TXOP-11a/g This indicates the current value of the Transmission Opportunity (TXOP) for
wireless a and g modes for the given parameter. This is the number of
milliseconds during which the NXC-8160 is allowed to transmit to a client
device once data packet transmission has been initiated.