These dashboard charts represent the categories of statistics relevant to all wireless stations (clients) on a controller and are designed to give you a real-time snapshot of the health of your wireless network. These charts indicate the following across all wireless stations on your network:
The key to understanding the data in these charts is to use your mouse on a chart as follows. To interpret one if the 10 sections of a graph, hover your mouse over a bar on the chart. This shows you the data range for that section and the number of stations that fall within in that data range. Right-click on that same bar and select Show Details to see the individual data points used to plot the chart. From this list of stations, click Open in the Diagnostics column to see the same four statistical charts for just that individual station and also a real-time event log for that station. These charts automatically refresh every minute.
Tips on interpreting the graphs appear when you click Graph Help, such as descriptions for each chart and a numeric version of the chart information. To redefine the amount of data displayed on a chart, Click Advanced, provide a new minimum and maximum value and then click Redraw.
This chart represents the distribution of each individual wireless station’s throughput over the range of the station with the lowest throughput and the station with the highest throughput. Throughput is defined as the sum of the transmitted and received bits-per-second for that station measured over the last two minutes. The data rate shown here in the Web UI cannot be generated from any one CLI command, but you can see the total bytes sent and received to an individual station using the command show statistics station-per-ap <apid> <macid>
Airtime Fairness is a measure of the distribution of channel utilization across all stations on that channel. For example, when all stations have similar channel utilization, you can say that airtime fairness is at its best.
Channel Utilization is the percentage of air time consumed on a given channel. Each wireless station’s utilization of the channel is calculated in each AP by measuring the air time consumed by unicast frames transmitted to and received from that wireless station. The formula used to calculate channel utilization is: Channel Utilization = (TX_airtime_consumed + RX_airtime_consumed) / time_duration * 100 (%)
The channel utilization for each individual station is measured over the last minute.
Retry % is the percentage of the total packets sent by the radio to the specified station with the 802.11 retry bit set. This metric provides insight on how often the radio needs to retransmit 802.11 packets to the specified station before an 802.11 ACK is received from that station.
This chart represents the distribution of packet loss across all wireless stations on this controller over the last two minutes. A packet is counted as "lost" when the configured number of transmissions/retries has been exhausted for that packet and no 802.11 ACK was received. Like the Station Throughput chart, each bar here represents a range of loss and how many stations fall within that range. The network is performing best when most stations are in the leftmost columns. The colors in the chart are a clue to the relative health of the traffic, darkest green being the best result (low loss).
This chart represents the range of signal strength across all wireless stations heard by the APs on this controller. As with the Station Throughput chart, it is divided into 10 equal ranges with the strongest signal activity to the right. Stations within any shade of green are being heard with good signal strength.
Each band in use (A/B/G/N) has a chart for both station input and output data rates. The Rx throughput graph represents throughput sent from the Station to the AP. The Tx throughput graph represents throughput sent from the AP to the station. To redefine the amount of data displayed on a chart, Click Advanced, provide a new minimum and maximum value and then click Redraw. If you right-click a chart and select Show Details, you will see the individual data items and the details that were used to plot the chart.