I used MPC5200B reference board from freescale with 3Com Wireless LAN card and ethernet.
Reference board acts as a WAP. It has 3 network interfaces.
Ethernet from reference board, Wireless Lan card and HSDPA interface using usb interface.

My question is like below.
Two notebooks are connected ftp server which is located from outside network through WAP(especillay HSDPA interface).
Two notebooks started to download a big file(about 600 ~ 700MB).
After aboud 1 hours, the connection of two notebooks are disconnected.

I checked log message at reference board using "sloginfo -w".
There are message like below.
Jan 01 00:00:01    5    14     0 ath0: mac 10.5 phy 6.1 radio 6.3
Jan 01 00:03:36    3    14     0 no flow: 2
Jan 01 00:50:36    5    14     0 en0ath0: device timeout
Jan 01 00:50:36    5    14     0 ath0: device timeout
Jan 01 00:50:38    1    14     0 ndx is 0

Is there anyone who can explain that what does it mean and how can I solve the problem?

And I put process lists for your information after the board is hang.
 pidin
     pid tid name               prio STATE       Blocked         
       1   1 procnto              0f READY                       
       1   2 procnto            255r RECEIVE     1               
       1   3 procnto            255r RECEIVE     1               
       1   4 procnto             10r RECEIVE     1               
       1   5 procnto             10r RECEIVE     1               
       1   6 procnto             10r RECEIVE     1               
       1   7 procnto             10r RUNNING                     
    4098   1 c/boot/devc-serpsc  10r RECEIVE     1               
    4099   1 proc/boot/slogger   24r RECEIVE     1               
    4100   1 proc/boot/pipe      10r SIGWAITINFO                 
    4100   2 proc/boot/pipe      10r RECEIVE     1               
    4100   3 proc/boot/pipe      10r RECEIVE     1               
    4101   1 c/boot/pci-mgt5200  21r RECEIVE     1               
    4102   1 proc/boot/devc-pty  10r RECEIVE     1               
    4103   1 proc/boot/qconn     10r SIGWAITINFO                 
    4103   2 proc/boot/qconn     10r CONDVAR     48060168        
    4103   3 proc/boot/qconn     10r RECEIVE     1               
    4103   4 proc/boot/qconn     10r RECEIVE     3               
    4104   1 /boot/devf-mgt5200  10r SIGWAITINFO                 
    4104   2 /boot/devf-mgt5200  10r RECEIVE     1               
    4106   1 proc/boot/io-usb    10r SIGWAITINFO                 
    4106   2 proc/boot/io-usb    21r RECEIVE     4               
    4106   3 proc/boot/io-usb    21r RECEIVE     1               
    4106   4 proc/boot/io-usb    10r RECEIVE     7               
    4106   5 proc/boot/io-usb    10r NANOSLEEP                   
    4106   7 proc/boot/io-usb    21r RECEIVE     7               
    8201   1 proc/boot/ksh       10r SIGSUSPEND                  
  397323   1 bin/devu-msm5500    10r SIGWAITINFO                 
  397323   2 bin/devu-msm5500    21r RECEIVE     4               
  397323   3 bin/devu-msm5500    10r REPLY       4106            
  397323   4 bin/devu-msm5500    21r RECEIVE     4               
  409613   1 usr/sbin/pppd       10r SIGWAITINFO                 
  516108   1 proc/boot/pidin     10r REPLY       1     

Wayne.