2017-05-19 7:04 GMT-05:00 Bastian Bloessl <address@hidden
<mailto:address@hidden>>:
Hi,
> On 19. May 2017, at 12:09, Cristian Rodríguez
<address@hidden
<mailto:address@hidden>> wrote:
>
> You will have to also add the corresponding entry in reverse
direction. It’s not in the script since I always used the WiFi
card of another PC.
> I did that as follows:
>
> sudo arp -s 192.168.123.1 12:34:56:78:90:ab -i wlp4s0
So you just set up one ARP entry.
>
> Then use Wireshark to monitor GNU Radio (that’s what you might
do at the moment) and also the WiFi card. This might help to
understand what frames are actually sent, if they are OK (MAC, IP,
BSS) and if they are successfully received by the WiFi card and
the SDR.
> If i do a ping from the interface tap0 to 192.168.123.2 (IP of
my wifi card) it doesn't work. The signal is going out of the USRP
but the Wifi Card of the computer is not taking it.
>
> ping -I tap0 192.168.123.2
>
> If i do a ping from the interface wlp4s0 to 192.168.123.1 (IP of
USRP B210) it doesn't work. The signal is NOT going out of the
Wifi card (i verifed that through wireshark).
>
> ping -I wlp4s0 192.168.123.1
As I said, you will have to actually look at the frame (BSS, MAC,
IP, …) and see if the fields are OK. Also put the receiver in
monitor mode to check if the packet is actually received. It’s a
configuration issue and you will have to find out where in the
network stack it gets dropped.
I've tried to solve the trouble the whole week. I don't think my
computer is able to support the communication between its Wifi card
and the USRP B210. When i do a Ping from the USRP to the wifi card (in
monitor mode), and it receives the ping, it stops working and in the
terminal which is executing the app nic.sh appear *ether type: IP. *In
the wireshark file for the side of Tx, it clearly have stoped working.
I've tried to solve it, but i don't think is a configuration problem.
On the other side, i got a computer and i'm try to communicate to it.
When i configure Monitor mode i can get packages.
What interface Mode do you think i should use? Ad-hoc or managed?
I've tried both but for me it doesn't work.
I've checked the frame and it looks as supposed. It shows the MAC of
the PC which is receiving, the MAC associated to the USRP and the
common flags.
I think it is a problem in the configuration file in the PC which is
receiving.
In that PC i'm doing the next:
Turn off the interface:
sudo ifconfig wlp2s0 down
Set the mode
sudo iwconfig wlp2s0 mode monitor/managed
Turn on the interface:
sudo ifconfig wlp2s0 up
Set in the channel that USRP is going to send
sudo iw dev wlp2s0 set freq 2472
Assign an IP in the network, the USRP is .1
sudo ifconfig wlp2s0 192.168.123.2
Modify the kernel's IPv4 network
sudo route add -net 192.168.123.0/24 <http://192.168.123.0/24> wlp2s0
Set a static route
sudo arp -s 192.168.123.1 12:34:56:78:90:ab -i wlp2s0
All the commands work, i checked with iwconfig, ifconfig, route, arp -a
*arp -a*
? (192.168.123.1) at 12:34:56:78:90:ab [ether] PERM on wlp2s0
*route*
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref
Use Iface
192.168.123.0 * 255.255.255.0 U 0 0 0 wlp2s0
*ifconfig*
wlp2s0 Link encap:Ethernet HWaddr e0:ca:94:68:06:a7
inet addr:192.168.123.2 Bcast:192.168.123.255
Mask:255.255.255.0
UP BROADCAST MULTICAST MTU:1500 Metric:1
*iwconfig*
wlp2s0 IEEE 802.11 ESSID:off/any
Mode:Managed Frequency:2.462 GHz Access Point: Not-Associated
Retry short limit:7 RTS thr:off Fragment thr:off
Power Management:on
Then i don't catch the problem.
*Finally, May you share to me the configuration file that you used
when you configure your PC in these experiments?*
Really, thanks a lot for your time.
Best regards,
Cristian