Hot answers tagged protocols
DoS attacks don't require any open ports on your side. They can just use all your bandwidth even if the ports are closed. How? The IP packet are sent from the attacker, and routed through several routers until it reaches your system. If the port is open, the connection succeeds. If not, your system can send back a "Port closed" message or simply drop the ...
If a port on the target machine is closed, it will either respond that the connection was refused or it will drop the packet silently. Ports being closed or "stealth" will not stop a DoS as the target will receive the packets whether it responds or not. In some cases ports are entirely irrelevant (see ping flood, smurf attack).
Only top voted, non community-wiki answers of a minimum length are eligible