search

seemoo-lab / nexmon_csi

Channel State Information Extraction on Various Broadcom Wi-Fi Chips
296 stars 121 forks source link

CSI collection from multiple ASUS Routers #95

Open yujianyuanhaha opened 4 years ago

yujianyuanhaha commented 4 years ago

greetings,

I am recently trying to collect CSI from multiple APs (ASUS Routers), most things goes fine despite I cannot collect CSI from 2nd or 3rd Routers. MERL_3AP1Sniffer2 The network is describe in figure above, I get 1st router connect to web via WAN port, and 2nd and 3rd connect to 1st via LAN port (along with DHCP disabled). In this way, a client can visit all APs by only connecting to any of them. e.g. the phone is connect to SSID of AP1, but it can visit AP2 and AP3 as well. Meanwhile, I got a router work as sniffer to tcpdump these channels to get CSI. Now I can easily get the CSI from 1st router AP1, however I never been able to collect CSI from AP2 nor AP3, the tcpdump just stucked for long with zeros packet captured.

I suspect it may have something to do with the way I jointly setup the network, the 3-APs network always assign AP1 for the wireless communication task only then later wired communicate with AP2. e,g. although we thought we establish the wireless link X -> AP2 via ping or iperf3, the indeed link is X -> AP1 & AP1 -> AP2 (illustrated below) MERL_3AP1Sniffer2 (1)

A simple steps I do is: (1), establish link X -> AP1 (via ping or iperf3), CSI_AP1 collected (2), shut off link X -> AP1, start X -> AP2; CSI_AP2 NOT collect, CSI_AP1 still collected (2), shut off link X -> AP1, start X -> AP3; CSI_AP3 NOT collect, CSI_AP1 still collected this is why I assume so

Some other information:

  1. If I pick a more general setup, 1st router connect to web via WAN port, and 2nd and 3rd connect to 1st via WAN port. This setup includes 3 WLAN groups. See figure attached below. MERL_3AP1Sniffer_WAN (1)

This setup I can succefully collect CSI from all APs, the only concern is there are so many devices that it may not always get 80MHz bandwidth fully used all the time.

  1. i print all jobs via ps and did NOT find wpa_supplicant running. I am not sure if it mean wpa_supplicant is disabled.

I am aware it may lay out of the scope of this project, however, is there any other "smart controller" of the router I should disable? Or any other better way to get CSI of 2nd and 3rd router？ @matthiasseemoo @schmittner @jlinktu@zeroby0 @YaohuaLee @mikeWangJC. Thanks in advance.

John-tw commented 3 years ago

@yujianyuanhaha hi !
This sentence "Now I can easily get the CSI from 1st router AP1, "
is mean that you get AP MAC address???? or PC Network card MAC address???