[Nebula 19.10 / AP FW 7.20] New MLO Setup Method for WiFi 7 APs

Zyxel_Lynn

With the release of Nebula 19.10 and AP firmware 7.20, Zyxel introduces major updates to Multi-Link Operation (MLO) for WiFi 7 access points. These changes impact all management modes—cloud-managed, standalone, and controller-managed—ensuring consistent behavior across deployment scenarios.

What Is MLO?

Multi-Link Operation (MLO) is a key advancement in WiFi 7 (802.11be). It allows access points and clients to connect across multiple bands simultaneously (e.g., 5 GHz + 6 GHz), delivering:

• Higher total throughput via aggregated bandwidth
• Stronger reliability by maintaining multiple active links
• Lower latency thanks to parallel transmission paths

Think of it as the wireless equivalent of link aggregation in wired networks.

Key Changes in Nebula 19.10 / AP FW 7.20

1. MLO Is Now Mandatory for 11be Radios

• Any SSID bound to an 802.11be radio will automatically enable MLO.
• The toggle option for MLO has been removed. Instead, NCC provides notes explaining this behavior.
• Supported security types for MLO:
  • Enhanced Open
  • WPA3-Personal
  • WPA3-Enterprise

This ensures both modern security standards and consistent MLO enforcement.

2. MLO Available in All Management Modes

• Previously limited to cloud-managed APs, MLO is now supported in:
  • Nebula Cloud
  • Standalone GUI
  • ZLD Controller (USG FLEX / ATP)
• Cloud-managed deployments on H-series APs allow per-band selection (2.4 GHz / 5 GHz / 6 GHz).
• Smart Mesh now fully supports MLO, improving wireless backhaul performance in mesh setups.

How to Enable MLO

• Cloud Mode: Go to Site-wide > Configure > Access Points > Radio Settings. Select 802.11be mode → MLO activates automatically.
• Standalone Mode: From the AP GUI, set the radio mode to 11be. All SSIDs on that radio inherit MLO.
• Controller Mode: In ZLD Controller, set Radio Objects to 11be mode to apply MLO.

MLO Group Limitations

• Maximum of 20 MLO-enabled SSIDs.
• Before 7.20 → Extra SSIDs were broadcast without MLO.
• From 7.20 onward → Extra SSIDs beyond the 20 limit are completely disabled.

This avoids confusion and enforces a clear operational boundary.

Two Common Misconfigurations

1. Exceeding the 20-SSID Limit
   • Assigning 21+ SSIDs to 11be radios → the last SSID in order is disabled.
2. Duplicate SSID Profiles on the Same Radio
   • MLO requires one-to-one SSID pairing between radios.
   • In 7.20, duplicate assignments result in the redundant SSID being fully disabled (instead of simply disabling MLO).

How to Verify MLO Is Active

Use CLI verification:

• Router> show wlan radio-profile all

Look for BE designation in band mode.

• Router> show wlan ssid-profile all

Example output:

Group ID 0: wlan2-slot1 <-> wlan3-slot1

Confirms correct pairing between radios.

Better Logging & Troubleshooting

• If SSIDs are disabled due to misconfiguration (e.g., too many groups or duplicate entries), event logs now clearly explain why.
• This reduces guesswork and improves troubleshooting efficiency.

Key Takeaways

• MLO is automatic with 802.11be mode—no more manual toggles.
• Stay within the 20 SSID MLO group limit.
• Avoid assigning the same SSID profile multiple times to the same radio.
• Use CLI or event logs to confirm MLO activity and troubleshoot.

These changes reflect Zyxel’s commitment to maximizing WiFi 7 performance while simplifying administration and preventing common misconfigurations.