3

I want to build a system for counting people based on wifi packets. I am using esp8266 for sniffing packets. But i read that android and iphones are now randomizing mac ids when they are not connected to any network. I thought of using probe requests but i saw that whenever i press refresh in mobile, the mac address is changed. So my program would detect it as a new device. This is what i am getting in different packets from the same device. 

Mac Address - da a1 19 9f bb 5c
d4 10 68 50 00 00 00 00 00 00 05 00 40 00 00 00 ff ff ff ff ff ff **da a1 19 9f bb 5c** ff ff ff ff ff ff e0 a4 00 0b 77 69 66 69 63 68 61 68 69 79 65 01 04 02 04 0b 16 32 08 0c 12 18 24 30 48 60 6c 03 01 04 2d 1a 6e 01 03 ff 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 dd 07 00 50 f2 08 00 00 00 7f 05 00 00 0a 02 01 3d 16 04 05 01 00 00 00 00 00 00 00 01 00 68 00

Mac Address - da a1 19 00 44 2f
d3 10 2e 50 00 00 00 00 00 00 0c 00 40 00 00 00 ff ff ff ff ff ff **da a1 19 00 44 2f** ff ff ff ff ff ff 90 c1 00 00 01 08 02 04 0b 16 0c 12 18 24 32 04 30 48 60 6c 00 00 34 34 50 43 01 08 82 84 8b 96 12 24 48 6c 03 01 0b 32 04 0c 18 30 60 07 06 49 4e 20 01 0d 14 23 02 13 00 46 05 f3 c0 01 00 04 05 04 00 01 00 14 dd 1a 00 50 f2 01 01 00 00 50 f2 02 02 00 00 50 f2 02 00 50 01 00 2e 00

Mac Address - da a1 19 ea d3 58
d7 10 67 50 00 00 00 00 00 00 03 00 40 00 00 00 ff ff ff ff ff ff **da a1 19 ea d3 58** ff ff ff ff ff ff a0 c2 00 0a 5a 54 45 2d 4b 62 72 79 59 47 01 04 02 04 0b 16 32 08 0c 12 18 24 30 48 60 6c 03 01 01 2d 1a 6e 01 03 ff 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 dd 07 00 50 f2 08 00 00 00 7f 05 00 00 0a 02 01 00 d7 75 eb 1d 7c e1 2f 06 a2 2c a3 df 01 00 67 00

I don't want to track individual user, my goal is to count the number of people in an area. Can I use any other packet type than probe request ? or will there be some similarity in probe request packets originating from same device, that way I can discard the new packet from the same device even if the source address (mac address) is changed.

Daga Arihant
  • 464
  • 4
  • 19
  • If you take a packet capture, do these phones send probe requests at a specific interval? If so, you can count them that way. – Ross Jacobs Apr 13 '20 at 20:09
  • The interval seemed very random and even the pattern for changing there mac ids. Sometimes its changed on every refresh button tap in mobile. ANd some mobiles don't even have the refresh button. – Daga Arihant Apr 15 '20 at 03:48
  • There are many people before you have tried for the past 10 years or so even before iPhone started to randomise the MAC address. You can only get the reliable MAC when you establish a connection. Plus your ESP8266 only works for 2.4GHz, so even you could find a way to count reliably, you only theoretically counts 50% of the presents. WiFi simply not a technology you could used for counting the crowd reliably. – hcheung Apr 16 '20 at 03:58
  • @hcheung I get the sense that it's more about getting a sense of foot traffic more than exact numbers. – Ross Jacobs Apr 16 '20 at 22:11

0 Answers0