Uninitiated noon question below.

A couple of days ago, this haprogram https://programming.dev/post/41491279

Now, during the phonecall with my ISP, the guy asked, “is your router an ASUS?” to which I answered, “yes and no, because it’s sold as a router but I have it in AP mode and my actual router is OpenWrt on a Raspberry Pi.” To which he replied “noice!”

How did he know the make of my access point? A few of my own thoughts are:

  1. he was referring to historical data (I’ve been a loyal customer of theirs for a looong time…) from a time when I was using the same topology (setup?) but without a VPN on the router, so the hostname of the AP (stored in /etc/hostname on the ASUS OS/firmware ?) was simply displayed on whatever software an ISP uses for troubleshooting through… an ARP? But aren’t ARPs limited to a LAN/they cannot resolve beyond a hop? Or perhaps a variant of DNS? How indeed do hostnames transmit? Are they in the IP header by default?
  2. as in 1 above, but he actively used nmap or some other recog program
  3. as in 1 above but from a time when I was in fact using the ASUS machine as a router
  4. my VPN is “leaking” - not likely, because all my traffic either goes through the wireguard interface on OpenWrt/RPi, or it doesn’t go anywhere…

If 1, 2 or 3: why do they keep historical data on me? Is it praxis?

  • emotional_soup_88@programming.devOPEnglish
    5·
    3 days ago

    Amazing! I had no idea that you can grab the vendor off of the first three octets. I shall try to refrain from - for academic purposes, of course - identifying devices and their vendors around me next time I’m at the coffee shop…

    • Clusterfck@lemmy.sdf.orgEnglish
      6·
      3 days ago

      For whatever it’s worth, that’s not a huge privacy violation. Most routers auto-identify devices. Most IP scan tools just identify the device by default too.

      If it’s a good enough public/hotspot network, they will have “client isolation” turned on and it’ll keep you from seeing any other devices but the actual network equipment.

      • emotional_soup_88@programming.devOPEnglish
        1·
        3 days ago

        I see. Well, now I understand why I see vendor names of connected hosts in my AP’s GUI. The vendor name of my robot vacuum, I will never be able to pronounce… (Something Chinese.)