Packet filtering is a firewall technique for controlling network access by monitoring outgoing and incoming packets and allowing them to pass or fail based on the source and destination Internet Protocol (IP) addresses, protocols, and ports. Packet filtering rule sets defined by network layer firewalls provide highly efficient security mechanisms. Packet filtering is also known as static filtering.
A node transmits a packet that is filtered and matched with predefined rules and policies during network communication. When a packet matches, it is either accepted or denied.
The source and destination IP addresses are checked during packet filtering. If the IP addresses of both parties match, the packet is considered secure and verified. Because the sender may employ a variety of applications and programs, packet filtering also examines the source and destination protocols such as User Datagram Protocol (UDP) and Transmission Control Protocol (TCP) (TCP). Source and destination port addresses are also validated by packet filters.
The source and destination IP addresses are checked during packet filtering. If the IP addresses of both parties match, the packet is considered secure and verified.
Because the sender may employ a variety of applications and programs, packet filtering also examines the source and destination protocols such as User Datagram Protocol (UDP) and Transmission Control Protocol (TCP) (TCP). Source and destination port addresses are also validated by packet filters.
