I read here, but that wasn't related.

If userA is connected to router and userB is connected to the same router, then how can userB sniff communications between userA and the router?

I've see a few videos where it says userB can sniff userA's traffic without ever explaining how that's possible.

Isn't it like two parallel bridges with no overlap? Hence sniffing shouldn't be possible.

  • didnt i answer you here already?security.stackexchange.com/questions/214555/… – Vipul Nair Aug 2 at 15:37
  • This is about how is about how can userB sniff userA's traffic. Where did you answer that? You just said he can MITM him. My question is how? I suppose there is something wrong with my analogy to the bridges, but I don't know what it is exactly – Honey Aug 2 at 15:40
  • Helping us to break security without showing knowledge is off-Topic here.But this kind of basic and a google search should show you how. – Vipul Nair Aug 2 at 15:45
  • I'm not asking for help to break security. I'm an iOS developer trying to understand some things. I've looked online e.g. here and they all say it's open to phishing. They don't explain why. My question is why can userA's connection be exposed to userB? – Honey Aug 2 at 15:51
  • "Isn't it like two parallel bridges with no overlap?" -- No. In modern hardware there might be a network switch attached to the router, that would make eavesdropping harder, but the router itself couldn't care less. It's more like two people in the same room shouting into the same speakerphone and promising not to listen to each other's conversations. – Ghedipunk Aug 2 at 16:06