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Subject: Re: Precise time synchronization via wifi interface (intel AX201
 iwlwifi driver)
To:     =?UTF-8?Q?Toke_H=c3=b8iland-J=c3=b8rgensen?= <toke@redhat.com>,
        linux-wireless@vger.kernel.org, linuxwifi@intel.com
References: <032f07e2-2771-619b-52b4-a25c8cd10f86@gmail.com>
 <87r1y72g60.fsf@toke.dk>
From:   Wei Liu <wei.liu1011@gmail.com>
Message-ID: <627ba0df-e4c6-7fe6-0d1a-e3d77d35c564@gmail.com>
Date:   Thu, 5 Mar 2020 14:57:37 +0100
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Hi Toke,

Yes, it is challenging, but IEEE802.1AS already takes consideration of 
IEEE802.11 MAC. So I count on the standardization to take care of the 
challenge :)

Point being that the Intel AX201 card claims Timesync feature 
(https://www.mouser.com/pdfDocs/wi-fi-6-ax201-module-brief.pdf), which 
is based on IEEE802.1AS. So there must be some way to run gptp like 
application on the AX201 intel card.

I appreciate any help here if someone has relevant experiences.

Best,

Wei

On 3/5/2020 12:29 PM, Toke Høiland-Jørgensen wrote:
> Wei Liu <wei.liu1011@gmail.com> writes:
>
>> Hi,
>>
>> I am trying to achieve precise time synchronization via wifi
>> interface.
> Erm, good luck with that? :)
>
> You do realise that there's a whole bunch of stuff going on below the
> driver level (listen-before-send, etc) that makes 'precise' timing (as
> in microsecond-accuracy like ptp)... shall we just say challenging?
>
> -Toke
>