Sitecom DC-210 Full Manual page 35

Private Port
Click <Apply> at the bottom of the screen to save the above configurations. You
can now configure other advance sections or start using the router (with the advance
settings in place)
This is the port number (of the above Private IP host)
that the below Public Port number will be changed to
when the packet enters your LAN (to the LAN
Server/Client IP)
35