Hello TP-Link Support and Community,

I’m experiencing a connectivity issue with my Deco XE75 mesh system operating in AP mode connected to my ISP router via Ethernet.

Setup details:

• Main Deco XE75 connected via Ethernet to the ISP router.

• Mesh operating in AP mode.

• WiFi on the ISP router is disabled.

• All devices (wired and wireless) obtain IP addresses in the same subnet from the ISP router DHCP.

• Devices connected to the mesh WiFi can ping each other and also ping wired devices connected directly to the ISP router (including my NAS).

• However, from a laptop connected via WiFi to the mesh, I cannot establish an SSH connection to the NAS, although SSH is enabled and working properly when the laptop is connected directly to the ISP router network.

• Before using the mesh, all connections including SSH worked fine directly through the ISP router.

What I’ve checked:

• No firewalls are enabled on the mesh nodes.

• The NAS is configured properly and SSH works from wired clients.

• Ping responses are consistent and reliable between all devices on the subnet.

• Firmware on the Deco XE75 nodes is up to date.

• The issue seems specific to TCP connections like SSH from WiFi clients connected to the mesh to wired devices on the ISP router network.

Additional observations & hypotheses:

• It appears the Deco XE75 in AP mode might not be bridging all TCP traffic correctly between WiFi clients and devices wired directly to the ISP router.

• ICMP traffic (ping) passes successfully, but TCP traffic on certain ports (like SSH port 22) does not reach the NAS.

• This behavior suggests possible issues with the mesh’s internal bridging or VLAN handling in AP mode.

• I suspect there might be limitations or bugs in the Deco XE75 AP mode implementation affecting layer 2 bridging or forwarding of TCP ports.

• The topology is straightforward: ISP router → main Deco XE75 (AP mode) → WiFi clients; NAS wired directly to ISP router.

• I have also verified that client isolation or AP isolation features are disabled.

Request:

Could you please assist in troubleshooting this issue? Is this a known limitation or bug of Deco XE75 AP mode? Are there recommended configurations or firmware versions that fix this behavior?
Additionally, any logs or diagnostic steps I can collect to help isolate the problem would be appreciated.

Thank you very much for your support.