title: Virtual networking devices in Linux
body: <p>Can someone explain in detail what are the differences of veth pairs and tap interfaces and how these devices connect to linux bridge or openvswitch.</p>
  
  <p>I found this:
  "Veth is a special net devices which were created in pair, I consider it as a method to change the traffic's direction, that is, when the out direction traffic is sent to veth device from Linux protocol stack, it was sent to another its mirror veth device, so the mirror one treats it as a in direction traffic and put it back to Linux protocol stack for further usage.</p>
  
  <p>Tap device is logical net device but have different with any other one: it allows user space program directly injecting traffic into Linux protocol stack, as well as it can retrieve traffic from the stack. It opens a tunnel to Linux protocol stack at level 2(or tun device at level 3) in user space, the stack will consider data from user space as in direction traffic"</p>
  
  <p>but it didn't gave me the whole picture.</p>
  
  <p>thanks in advance!</p>