Packet filtering is a process of Passing data Packets through a network Interface based on Source and Destination addresses, ports, protocols, keywords or URL�s.
During Packet filtering, the packet filter (software or hardware) normally would not look into the headers of the packets but instead it checks the Body of the Packets against the Security Policies implemented for the outgoing traffic.
Packet filtering is normally used in combination with a firewall. Today, Latest firewalls are being made with the capability of packet filtering pre-installed.
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