SSID with only 6G radio enabled is being broadcast only briefly and subsequently disappear

Zyxel_JoyLee

Wi-Fi 6E (802.11ax in 6GHz) station and Wi-Fi 7 (IEEE 802.11be) station have difficulty detecting 6GHz SSIDs due to the following reasons：

In IEEE 802.11 standards, the restriction on uncontrolled active scanning in the 6 GHz band is primarily defined in IEEE 802.11ax (Wi-Fi 6E) and IEEE 802.11be (Wi-Fi 7).

The key IEEE mechanism enforcing this restriction is Out-of-Band Discovery (OOB Discovery) and Reduced Neighbor Report (RNR).

1.IEEE 802.11ax-2021 (Wi-Fi 6E) & IEEE 802.11be (Wi-Fi 7)

￭ STA (Station) devices are not allowed to perform unsolicited active scanning (i.e.,sending Probe Requests) in the 6 GHz band.

￭ Instead, STAs must rely on:

a. Passive scanning (listening for AP beacons)

b. Out-of-Band Discovery (OOB Discovery) using Beacons or Probe Responses from 2.4 GHz or 5 GHz bands to obtain 6 GHz AP information.

c. Reduced Neighbor Report (RNR), where APs operating in 2.4 GHz or 5 GHz provide information about 6 GHz availability.

2. IEEE 802.11ax & IEEE 802.11be specify that:

￭ Active scanning in 6 GHz is limited to cases where the STA is operating under controlled conditions, such as when it has prior knowledge of an AP (e.g., from RNR or OOB Discovery)

￭ Uncontrolled active scanning (unsolicited probe requests)is not allowed to reduce interference and comply with regulatory requirements(e.g., AFC - Automated Frequency Coordination).

Since 6G utilizes the Out-of-Band Discovery mechanism, it embeds 6GHz network information (such as BSSID, channel, and SSID) in Beacons or Probe Responses transmitted over the 2.4GHz/5GHz bands. This allows client devices to obtain a list of available APs without directly scanning the 6GHz band. For example, when a client device connects to a 5GHz network, the AP can use the Reduced Neighbor Report (RNR) to inform the client about the availability of the same SSID in the 6GHz band. Based on the above information about 6GHz, we recommend enabling SSID on 5GHz or 2.4GHz alongside 6GHz, rather than using 6GHz only.