HostAP + WDS + bridging high ping times

[Iwan Kilis]

Hello all,

i have problem about wds implementation using hostap WDS and bridging.

i'm using pebble v4.1, soekris 4521 and 2 demarctech 200mW pcmcia.


client ------ omni antenna            omni antenna ------ client
    	      wlan0                   wlan0
               grid antenna ---------- grid antenna
               wlan1                   wlan1


the system been running about 6 month using rip routing and the ping is 
about 4ms between APs and about 12ms from client to client.

now i'm trying to use WDS + bridge(STP) to achieve same topology

              AP1                      AP2
client ---- omni antenna             omni antenna ---- client
             wlan0                    wlan0
             wlan0wds0 ----- WDS ---- wlan0wds0


after i changed to WDS, the ping went to 20 - 100 ms between APs
is there anything i can do to optimize the configuration ?
below is both ap config.

distance is 4km and the omni is 15dBi.

#### AP1
/usr/sbin/brctl addbr br0
/usr/sbin/brctl setbridgeprio br0 1
/usr/sbin/brctl stp br0 on
/usr/sbin/brctl addif br0 eth0

/sbin/ifconfig br0 x.x.x.x netmask x.x.x.x up

/sbin/iwconfig wlan0 essid test
/sbin/iwconfig wlan0 mode master
/sbin/iwconfig wlan0 enc xxxxxxxxxxxxxxxxxxx restricted
/sbin/iwconfig wlan0 channel 1
/sbin/iwconfig wlan0 rate 11M auto
/sbin/iwpriv wlan0 beacon_int 100
/usr/local/sbin/prism2_param wlan0 ap_bridge_packets 0

/sbin/ifconfig wlan0 0.0.0.0 up
/usr/sbin/brctl addif br0 wlan0

/sbin/iwpriv wlan0 wds_add 11:11:11:11:11:11
/sbin/ifconfig wlan0wds0 0.0.0.0 up
/usr/sbin/brctl addif br0 wlan0wds0

##### AP2
/usr/sbin/brctl addbr br0
/usr/sbin/brctl setbridgeprio br0 2
/usr/sbin/brctl stp br0 on
/usr/sbin/brctl addif br0 eth0

/sbin/ifconfig br0 x.x.x.x netmask x.x.x.x up

/sbin/iwconfig wlan0 essid test
/sbin/iwconfig wlan0 mode master
/sbin/iwconfig wlan0 enc xxxxxxxxxxxxxxxxxxx restricted
/sbin/iwconfig wlan0 channel 1
/sbin/iwconfig wlan0 rate 11M auto
/sbin/iwpriv wlan0 beacon_int 100
/usr/local/sbin/prism2_param wlan0 ap_bridge_packets 0

/sbin/ifconfig wlan0 0.0.0.0 up
/usr/sbin/brctl addif br0 wlan0

/sbin/iwpriv wlan0 wds_add 22:22:22:22:22:22
/sbin/ifconfig wlan0wds0 0.0.0.0 up
/usr/sbin/brctl addif br0 wlan0wds0
-----

Thanks for any advice
Iwan Kilis