behaviour with two network cards
Hi there, I'm new to linux in general, and I've just started using debian as a desktop Os.
In my desktop setup I have two network cards on the same subnet (i'm going to be using it as a router with NetEm for my 4rth year project).
What surprised me was the behavior of these cards. It seems as though one interface handles internal traffic, while the other handles external, internet traffic. AS i mentioned they're on the same subnet so I'm surprised. I've attached a screenshot (outlined in true mspaint style).
Am I just imagining this or is this the default behavior of linux?