Handling of FCS Errors

Jouni Malinen jkmaline at cc.hut.fi
Mon May 26 13:16:56 EDT 2003

On Mon, May 26, 2003 at 03:49:27PM +0200, Kilian Rall wrote:

> Does anybody know how the HostAP driver handles FCS- Errors?

It doesn't, this is done in Prism2 firmware..

> Does the reciever only drop damaged packets and the sender retransmits them when a timeout expires, 
> or does the reciever send Acknowlege- packets and No- Acknowledge packets like it is done when you have a sliding window protocol?

The receiver sends ACK frames for unicast packets that had correct FCS.
This is implemented in Prism2 firmware, so you will not find it from the
driver source code.

> When is prism2_txexc started?

It is used when Prism2 firmware reports a failed transmit.

Jouni Malinen                                            PGP id EFC895FA

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