[Ns-developers] management of wifi association in infrastructure mode

[Mathieu Lacage]

On Thu, 2008-11-27 at 13:29 +0000, Gustavo Carneiro wrote:
> 
> 
> 2008/11/26 Mathieu Lacage <mathieu.lacage at sophia.inria.fr>
>         
>         On Wed, 2008-11-26 at 15:55 +0000, Gustavo Carneiro wrote:
>         
>         > 3) In the AP, if it doesn't receive an ACK for the
>         > ASSOCIATION_RESPONSE, re-send the ASSOCIATION_RESPONSE when
>         the ACK
>         > timer expires or the ACK is received with error; repeat this
>         until 7
>         > times or until the ACK is received.
>         >
>         > I think this is the most logical solution.  We know that
>         management
>         > frames have to follow the same basic DCF transmission rules
>         as normal
>         > data frames.  And for both management and data frames it
>         makes perfect
>         > sense to treat a unreadable ACK as a missing ACK and trigger
>         a
>         > retransmission accordingly.
>         
>         
>         We already do this 
> 
> 307565309ns NqstaWifiMac:Receive(): assoc completed
> 307581309ns MacLow:SendAckAfterData(0x8a8620)
> 307581309ns MacLow:ForwardDown(0x8a8620, 0x8aada0, 0x7fffde836c30, wifia-6mbs)
> 
> 307581309ns MacLow:ForwardDown(): d0:00:00:00:00:02 send CTL_ACK,
> to=d0:00:00:00:00:01, size=14, mode=wifia-6mbs, duration=0ns, seq=0x0
> 307625412ns MacLow:ReceiveError(0x899800, 0x8aaf90, 0.71913)
> 307625412ns MacLow:ReceiveError(): d0:00:00:00:00:01 rx failed 
> 
> 307640872ns MacLow:NormalAckTimeout(0x899800)
> 307640872ns MacLow:NormalAckTimeout(): d0:00:00:00:00:01 normal ack timeout
> 307640872ns NqapWifiMac:TxFailed(0x899650)
> 307640872ns NqapWifiMac:TxFailed(): assoc failed with sta=d0:00:00:00:00:02
> 
>  
> According to my logs, we do not do this at all.  AssociationResponse
> is transmitted once, the ACK is lost, and re-transmission is not
> attempted, the AP simply gives up immediately.

Ah. I see. This is a bug. Can you try the attached patch ?

Mathieu

> 

> 
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