My question involves the delays involved with changing which physical socket your ethernet cable is connected to.

I am aware that if you are connected to a router on a network and then change which physical socket on that router you are using you will gain very small additional delays initially. However I am curious as to what causes these delays. I originally thought it was to do with the infromation stored in the routing table and whether that was allocated to a specific socket on the router or not. Although, if your IP address is the same then I don't understand why there would be delays because I would of assumed that any information within the router was linked to an IP address rather than a physical socket.