RTS/CTS not fully disabled?

ahuguet at cttc.es ahuguet at cttc.es
Wed May 30 06:15:34 EDT 2007

> You should be able to read the current value with 'hostap_rid wlan0 get
> fcb5' and set the new value with 'hostap_rid wlan0 set fcb5 7c 00' (the
> value is little endian, so swapped bytes here). Please let me know
> whether this helps in your test setup.

Thank you Jouni, this worked like a charm.

Indeed the default value was 7c 04 (data rate fallback on third through
seventh retries, begin RTS control on third retry)

Personally, I don't see how that could be a correct default value,
considering that RTS threshold is off by default, and that, in my test,
when the RTS/CTS happened, no frame was actually delivered, so the cards
gained nothing by using the RTS/CTS (they rather started a RTS-CTS loop)

In other words, when the user sets iwconfig wlan0 rts off, this should
also put to 0 the 8 most significant bits on cnfFallbackCtrl to avoid the
RTS usage, and the described loop.

Also, and this I'm not yet fully sure, even if the default cnfFallbackCtrl
value claims that it will use the rate fallback on third retry, I'd say
that I've seen the cards still using the rate that was fixed by the user.
That is, the expected behavior; because the iwconfig rate command did not
use the "auto" after the rate value.

Thank you very much again for your help Jouni, for this will allow, most
likely, to perform that test with the 10 node configuration.

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