Ethereal-users: [Ethereal-users] why my AP have 10% packet loss

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From: "yuxiao jia" <yxjia@xxxxxxxxxxxxxxx>
Date: Thu, 22 Apr 2004 18:12:32 -0400
Hi All,
 
I am doing the 802.11b performance tests. My test-bed configuration is following
 
                         Ethernet LAN                                  ( WLAN)
Traffic Generator ----------------------|   Access Point (AP) |  ................... | Wireless Workstation (WS) |
                                           eth0                        wlan0                     eth0
                                                                                  
I send UDP CBR traffic from Traffic Generator to AP from fast ethernet, then from AP to WS by WLAN 802.11b
 
In AP. eth0 is fast ethernet Interface, wlan0 is Linksys IEEE802.11b PCMCIA wireless NIC
 
In WS, the eth0 is Orinoco Gold IEEE802.11b PCMCIA wireless NIC
 
In WLAN part, we set infrasture mode. AP is "Master" . the ws is "managed"
 
We catpture the number of packets in three places, one is in eth0 in AP, one is in wlan0 in AP, the left is eth0 in WS
 
We use ethereal (also tcpdump)
 
We found when we send packet size 100 bytes, rate 1250 pkt/sec (1Mbit), the packet loss In AP is 10% when packet forwarding from Ethernet NIC "eth0" to Wireless NIC "wlan0". I am wondering why it happen?
 
We set eth0 and wlan0 in AP promiscus mode when capturing..
 
Do I need set up Wireless NIC (wlan0) to monitor mode as I capture UDP packets?? if needed, how?
 
Thanks a lot
 
Regards
 
yuxiao