Linux wireless stack question

Linux wireless stack question

[hamsa Al Janoob]

Hi all,

This question is directed to the authors (or any one with solid knowledge 
of) of the new ieee80211 (or mac80211) wireless stack, which can be found in 
Fedora 7 and expected to be part of the new kernel releases:

Where is the exact location of the implementaiton of the binary exponential 
backoff procedure in the source code? Also, where can I find the 
declarations of the min and max values of the contention window?

Regards,
Maali

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Re: Linux wireless stack question

[Tomas Winkler]

On 7/27/07, hamsa Al Janoob <mms82@hotmail.com> wrote:
> Hi all,
>
> This question is directed to the authors (or any one with solid knowledge
> of) of the new ieee80211 (or mac80211) wireless stack, which can be found in
> Fedora 7 and expected to be part of the new kernel releases:
>
> Where is the exact location of the implementaiton of the binary exponential
> backoff procedure in the source code?
I'm speaking for mac80211 only, there is no such implementation. This
stuff is mostly done directly by hw or firmware.. I'm not familiar
with all the drivers though.
Also, where can I find the
> declarations of the min and max values of the contention window?
look for cw_max cw_min. It is brought to driver through conf_tx handler
Tomas
> Regards,
> Maali
>
>
Tomas _________________________________________________________________
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Re: Linux wireless stack question

[maali Al Janoob]

Thank you for the reply.
What I want to do basically is changing the backoff algorithm to implement a 
modified protocol in Linux (for my thesis). From what I know, the firmware 
is inaccessible. Are you aware of any available source code for a firmware 
of any driver?

Please, I need this help so badly to continue my thesis work, any ideas?

Thanks,
Maali


>From: "Tomas Winkler" <tomasw@gmail.com>
>To: "hamsa Al Janoob" <mms82@hotmail.com>
>CC: linux-wireless@vger.kernel.org
>Subject: Re: Linux wireless stack question
>Date: Fri, 27 Jul 2007 16:28:49 -0700
>
>On 7/27/07, hamsa Al Janoob <mms82@hotmail.com> wrote:
> > Hi all,
> >
> > This question is directed to the authors (or any one with solid 
>knowledge
> > of) of the new ieee80211 (or mac80211) wireless stack, which can be 
>found in
> > Fedora 7 and expected to be part of the new kernel releases:
> >
> > Where is the exact location of the implementaiton of the binary 
>exponential
> > backoff procedure in the source code?
>I'm speaking for mac80211 only, there is no such implementation. This
>stuff is mostly done directly by hw or firmware.. I'm not familiar
>with all the drivers though.
>Also, where can I find the
> > declarations of the min and max values of the contention window?
>look for cw_max cw_min. It is brought to driver through conf_tx handler
>Tomas
> > Regards,
> > Maali
> >
> >
>Tomas _________________________________________________________________
> > Express yourself instantly with MSN Messenger! Download today it's FREE!
> > http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/
> >
> > -
> > To unsubscribe from this list: send the line "unsubscribe 
>linux-wireless" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> >
>-
>To unsubscribe from this list: send the line "unsubscribe linux-wireless" 
>in
>the body of a message to majordomo@vger.kernel.org
>More majordomo info at  http://vger.kernel.org/majordomo-info.html

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Re: Linux wireless stack question

[Johannes Berg]

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On Sun, 2007-07-29 at 18:21 +0400, maali Al Janoob wrote:

> What I want to do basically is changing the backoff algorithm to implement a 
> modified protocol in Linux (for my thesis). From what I know, the firmware 
> is inaccessible. Are you aware of any available source code for a firmware 
> of any driver?

Nope, none freely available. There are some efforts (prism54, bcm43xx)
to write free firmware for some devices, but none of them are in a stage
that could be used. (prism54: dunno, but I know it's not usable;
bcm43xx: only partially reverse engineered)

> Please, I need this help so badly to continue my thesis work, any ideas?

Play some connections to get firmware under NDA?

johannes

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Re: Linux wireless stack question

[Alfredo Matos]

On Mon, 2007-07-30 at 13:33 +0200, Johannes Berg wrote:
> On Sun, 2007-07-29 at 18:21 +0400, maali Al Janoob wrote:
> 
> > What I want to do basically is changing the backoff algorithm to implement a 
> > modified protocol in Linux (for my thesis). From what I know, the firmware 
> > is inaccessible. Are you aware of any available source code for a firmware 
> > of any driver?
> 
> Nope, none freely available. There are some efforts (prism54, bcm43xx)
> to write free firmware for some devices, but none of them are in a stage
> that could be used. (prism54: dunno, but I know it's not usable;
> bcm43xx: only partially reverse engineered)
> 

What about atheros dadwifi [1] and openHAL [2] ? Could this help ?

Alfredo.

[1] - http://madwifi.org/wiki/DadWifi
[2] - http://madwifi.org/wiki/OpenHAL

Re: Linux wireless stack question

[Johannes Berg]

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On Mon, 2007-07-30 at 13:08 +0100, Alfredo Matos wrote:

> What about atheros dadwifi [1] and openHAL [2] ? Could this help ?

Not entirely sure, but I very much doubt they do backoff in software.
Similary to bcm43xx, I expect they set the backoff parameters from the
driver but the actual algorithm will be implemented in hardware or
firmware. But I really don't know. I guess you can check out the code
and go through it.

johannes

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madwifi question

[maali Al Janoob]

Does madwifi driver support ad hoc oepration?

Thanks

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Re: madwifi question

[Michael Renzmann]

Hi.

> Does madwifi driver support ad hoc oepration?

Yes.

Bye, Mike