CTS 308: Reduced Neighbor Report

From Clear To Send: Wireless Network Engineering Rowell Dionicio and François Vergès

Jiri Brejcha joins us on this episode to discuss his testing of 6 GHz capable clients (iPad and Google Pixel) and how they discovery 6 GHz Wi-Fi networks. Jiri demonstrates how important the Reduced Neighbor Report plays an important role in 6 GHz AP discovery.

Jiri is an enterprise architect at Cisco UK and part of the Cisco Live team. He’s also a core member of the WLAN Pi team.

In his lab, he has a Cisco 6 GHz access point broadcasting a few SSIDs on different bands. He wondered how an iPad and Pixel will detect a 6 GHz-only SSID. Do you need to have APs operate on PSC only?

Inside of a beacon frame, you’ll find a Reduced Neighbor Report (RNR) Information Element. The RNR contains important details such as the channel used by neighboring access points. This can be one access point or a group of access points. You’ll find this information in the Neighbor AP Information Fields

Target Beacon Transmission Time (TBTT)

https://twitter.com/jiribrejcha/status/1591188679086571520?s=20&t=ZNWHL-brEYi2fWnDc3Wtxg

Resources

* Section 9.4.2.170 of the 802.11-2020 standards

* https://www.jiribrejcha.net/2022/11/google-pixel-6-wi-fi-6e-scanning-and-6-ghz-ssid-discovery/

* https://www.jiribrejcha.net/2022/11/ipad-pro-wi-fi-6e-scanning-and-6-ghz-ssid-discovery/

* Apple specifications: https://support.apple.com/en-us/HT202068