[Madwifi-devel] Chaging cwmin & cwmax

[710 <710...@gm...>]

Hi.

I want to change the size of contention window.
As far as I know, in 802.11b
CWMIN=31.
CWMAX=1023.

I want to change these to
CWMIN=255.
CWMAX=4095.

As people suggest, I tried WMM QoS support from
http://madwifi.org/wiki/UserDocs/UsersGuide.
However, this seems not working with monitor mode as the following shows.

=====================================================================
ath0      IEEE 802.11b  ESSID:"eBox"  Nickname:""
          Mode:Monitor  Frequency:2.462 GHz  Access Point:
00:02:6F:44:CD:96
          Bit Rate=1 Mb/s   Tx-Power:18 dBm   Sensitivity=0/3
          Retry:off   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=0/94  Signal level=-98 dBm  Noise level=-98 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

[root@localhost scripts]# iwpriv ath0 get_wmm
ath0      get_wmm:1
[root@localhost scripts]# iwpriv ath0 get_cwmin 0 0
ath0      get_cwmin:5
[root@localhost scripts]# iwpriv ath0 cwmin 0 0 8
[root@localhost scripts]# iwpriv ath0 get_cwmin 0 0
ath0      get_cwmin:5
=====================================================================

Q1. Is there a way to change cwmin&cwmax with WMM support?



I found the following code from ath/if_ath.c
=====================================================================
static struct ath_txq *
ath_txq_setup(struct ath_softc *sc, int qtype, int subtype)
{

..
    qi.tqi_cwmin = HAL_TXQ_USEDEFAULT;
    qi.tqi_cwmax = HAL_TXQ_USEDEFAULT;
...

=====================================================================

Q2. What if I set qi.tqi_cwmin=255 & qi.tqi_cwmax=4095?

Q3. Is there any other way to change these values?

Q4. If there is a way to change cwmin&cwmax, how can I verify them? Any
suggestion?

Thanks,
Ki-Young