What is packet filtering?

What is packet filtering? packet filtering firewall watch outgoing incoming packets to control network access. And let them pass on the source and destination. Internet protocols and ports.

Layer of firewall describe setting of filtering rule. That supply extremely security. Mechanism. We know packet filtering as static filtering too. That check source and destination ip address packet filttering verify source. And it used which traffic is allowed and which one denied.

For example If one person or hacker try to access in your network and a hacker leave a message that the information probably tell the hacker how you are protect from your network. You probably want to know have your packet firewall and a hacker try to arrive a port 80and your packet filtering send back a message that port 80 is being filtered. And a hacker have to spend more time to slip through the fire wall.