AX200 with Fine Timing measurement leads to packet loss

[Sgued]

Hello,

We are working on F.T.M. using the AX200 wireless card, and we observed that when doing regular F.T.M. requests, we observed high rates of packet loss. We initially assumed it was an error in our own software but we are able to reproduce the issue using the netcat and iw, which leads us to believe that the issue doesn't come from our software.

We use two devices running both Intel J1900 CPUs with AX200 wireless cards. One of them is setup as an access point, the other connected as a wireless client to the first one.
We are able to make Wireless requests from the client to the access point and get responses. However, when we make repeated F.T.M. measurements, we observe a high amount of UDP packet loss on from the client as a receiver (when the client is sending packets, no loss is observed). There can be periods of up to multiple seconds where no packets can be received. The packets are correctly being sent since they can be observed by a third device using wireshark in monitor mode, which leads us to believe that the issue is on the receiver side.

If the F.T.M. requests are made with a destination mac address that is not the one of the AP, and thus receives no response, no packet loss is observed.

We tried switching the AX200 card of the client for another AX200 card, but the result was the same.

Both the access point and the client are running Debian 10 with the 5.10  Linux kernel from the buster-backport repos, with the backport-iwlwifi driver core61 release, using the  iwlwifi-cc-a0-63.ucode firmware.

We would like to know if there is a way for us to prevent such packet loss from happening.

Thanks

[David_G_Intel]

Hello Sgued

Thank you for posting on the Intel️® communities. Please share with us more information on the current setup and the systems that you tested, make sure to include the Intel® System Support Utility (Intel® SSU) results 

• Download the Intel SSU https://downloadcenter.intel.com/download/26735/Intel-System-Support-Utility-for-the-Linux-Operating-System
• Open the application and select "Everything" click on "Scan" to see the system and device information. By default, Intel® SSU will take you to the "Summary View".  
• Click on the menu where it says "Summary" to change to "Detailed View".  
• To save your scan, click on "Next", then "Save".  

Regards, 

David G 

Intel Customer Support Technician 

[Sgued]

Hello David, thanks,

I ran the SSU script on both devices and I send the output as an attachment.
The "AP_localhost.txt" file corresponds to the device acting as an access point and FTM responder, while the "client_localhost.txt" corresponds to the client device making the FTM requests.

I want to also report that on both devices, the scripts showed that "This product is not  supported on this operating system". On the access point device, it also showed 4 times: ping: enp4s0: Name or service unknown.

Regards, Sosthène G

[David_G_Intel]

Thank you for the information provided, we are currently working on this request and the updates will be posted on the thread.

Regards, 

David G 

Intel Customer Support Technician 

[David_G_Intel]

To continue with the investigation process, check if this same problem occurs in Ubuntu. Once you try, please let us know the results and share the logs with Ubuntu again.

Regards, 

David G 

Intel Customer Support Technician 

[David_G_Intel]

Were you able to check the previous post?  

Let us know if you still need assistance.  

Best regards,  

David G.  

Intel Customer Support Technician  

[David_G_Intel]

We have not heard back from you, so we will close this thread. If you need any additional information, please submit a new question as this thread will no longer be monitored.   

Best regards,  

David G. 

Intel Customer Support Technician