1 ip address several ports listening each taking turns.
1 packet goes to port 1
1 to port 2
1 to port 3 etc.
then back to port1
if you get a new packet the port that gets the first packet will handle the rest of the conversation.
Now say the cable on port 3 is cacked. The router will still send packets to that port as part of the round robin. That would generate odd timeouts of a ip address like I saw.
thanx,
bill