So..i had this argument with my networks teacher. He said that some people complains about router crashes due to many entrys on NAT tables on a router. I didnt understand and i asked: "If the application uses the same port, why does the router crash?. It should have only one entry (pc-ip,pcport;public-ip,public-port)". And he said: "it doesnt matter its using the same port". I got the idea that NAT creates an entry for every packet that passes trought it. Iam assuming NAT with overloading as you might have guessed. So the questions are: 1-How does nat entrys are created? On a packet basis or connection basis? I mean: suppose i send a udp packet..does the router create an entry? 2-When i start a TCP connection, does the router create a persistant nat entry until the connection closes? 3-Was my teacher right? The NAT table can overload assuming an aplication on the same port sending packets? Thanks in advance.