* [ath9k-devel] Fwd: some queries on open-ath9k f/w
2015-03-15 6:52 ` [ath9k-devel] Fwd: some queries on open-ath9k f/w Oleksij Rempel
@ 2015-03-15 23:49 ` Mathy Vanhoef
0 siblings, 0 replies; 2+ messages in thread
From: Mathy Vanhoef @ 2015-03-15 23:49 UTC (permalink / raw)
To: ath9k-devel
Hi Jithu,
The ath9k_htc firmware can be seen as a driver that happens to run on
the USB dongle. What I mean with this is that the firmware code is
quite similar to a normal driver (e.g. madwifi or ath9k). While it has
some control over MAC behavior, it doesn't have full control. Most of
this control is through memory mapped registers, so you can configure
or enable/disable some settings. The code running on the actual
wireless chip cannot be changed.
As far as I know, you cannot modify the content/structure of ACKs that
the wireless chip transmits. Perhaps you can simulate this in software
(i.e. in the firmware) though. Assign a random MAC addresses (or
disable sending ACKs if possible), and send ACKs in the firmware
itself. You'll have to be careful so this is done fast enough though
(quickly handle and detect packets, use a transmit queue that
instantly transmits, etc).
Kr,
Mathy
On Sun, Mar 15, 2015 at 7:52 AM, Oleksij Rempel <linux@rempel-privat.de> wrote:
>
> This is probably better place for this question.
>
> -------- Weitergeleitete Nachricht --------
> Betreff: some queries on open-ath9k f/w
> Datum: Wed, 4 Mar 2015 00:21:25 -0700
> Von: Jithu Joseph <jithu83@gmail.com>
> An: ath9k_htc_fw at lists.infradead.org
>
> Hi,
>
> I want to play around with Link Layer Acks . I took a quick looks at
> the open sourced f/w code in github and couldn't find the Medium
> Access code (wherein i expected to find some link layer ack setting).
>
> Before getting into more specific queries , can someone tell whether
> it is possible to do such low level stuff (given that we have access
> to a an open-source f/w - or is it done fully in hardware and we don't
> have a way to disable link layer acks , or is it done at the host
> driver level )
>
> Ideally I am trying to implelemet something like this paper for a class
> project
> https://www.usenix.org/conference/atc14/technical-sessions/presentation/salameh
>
> <snip>
> In this paper, they propose TCP/HACK (Hierarchical ACKnowledgment), a
> system that applies cross-layer optimization to TCP traffic on WiFi
> networks by carrying TCP ACKs within WiFi's link-layer
> acknowledgments. By eliminating all medium acquisitions for TCP ACKs
> in unidirectional TCP flows, TCP/HACK significantly improves medium
> utilization, and thus significantly increases achievable capacity for
> TCP workloads.
>
> </snip>
>
>
> This is the code I looked into
> https://github.com/qca/open-ath9k-htc-firmware/tree/master/target_firmware/wlan
>
>
> --
> Thanks and Regards
>
> Jithu Joseph
> +1 (385) 210 9875
>
> _______________________________________________
> ath9k_htc_fw mailing list
> ath9k_htc_fw at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/ath9k_htc_fw
>
>
>
>
> _______________________________________________
> ath9k-devel mailing list
> ath9k-devel at lists.ath9k.org
> https://lists.ath9k.org/mailman/listinfo/ath9k-devel
>
^ permalink raw reply [flat|nested] 2+ messages in thread