802.11ax, to OFDMA or not to OFDMA

The 802.11ax amendment was built to increase the efficiency of WiFi. One of the new features is OFDMA or the capability to send data to several stations simultaneously, multi-user operations.
One of the benefits of OFDMA is to decrease the duration it takes to send the data to several stations in relation to single-user operations. Especially for smaller frame sizes, but for which?

In this blog, I will check the trade-off between SU and MU operations in 802.11ax for three typical scenarios.
You will be amazed, I was

Read More »

802.11 Compressed BlockAck, Two Different Behaviors

When interpreting wireless captures it is not always easy to capture the data frames because they are usually sent with complex modulation and coding schemes. The quality of the capturing NIC is also important.
But management and control frames are easier to capture because they are sent with legacy frame format (802.11b/g or 802.11a).
The BlockAcknowledge frame (BA) is the frame used by the receiving station to send back to the transmitter the status for what the receiver has received without corruption.
The last two years I have seen two different behaviors for the BA, one according to the standard and the other with a strange behavior
Let us dig into it

Read More »

Comparing 802.11ax Frame Capturing on a Jetson Nano vs Cisco AP

Frame capturing of 802.11frames, WiFi, is a important task in managing and troubleshooting WiFi networks. In the earlier days there were different methods of capturing these frames, but now when 802.11ax (WiFi6) is in the marked the variety in methods is limited.

Capturing the management and control types of frames that normally use legacy frame formats like 802.11b/g in the 2.4GHz band and 802.11a in the 5GHz is still easily done, but capturing the data frames with 802.11ax frame format is more tricky.

I will in this blog compare 802.11ax frame capturing using a Jetson Nano with Intel ax200 wireless NIC and a Cisco C9115-AXI in sniffer mode

Read More »