There is no difference between port mapping and port forwarding and both are equal and in some router they are used instead of the other one .
The meaning of these names is that "New connections from the outside to a certain port or port range go to a designated LAN machine. The ports are determined by the kind of server you want to run, (e.g. 80 for a web server) and the IP is the private LAN IP of your web server."
Port forwarding
port filtering
It strictly depends on the model. Most routers have to be restarted in order to enable port forwarding.
forwarding packets to the port that is connected to the destination node
forwarding packets to the port that is connected to the destination node
yes
Well Port Forwarding is really only, opening ports and making them special to let a one connection on it. The main purpose for me is for gaming, you need to port forward for a game to run a dedicated server if the game allows, like Quake 3 arena, or GTA's, or Call of Duty's ect.
well i don't think the question given is a correct question because like give the difference between the keyboard port and the usb port
Port Fast is used to bring an interface used as an access or trunk port to a forwarding state from a blocked state.
Source Port
Yes
Problems with integrity of network packages, also some routers do not handle properly port forwarding.