static packet filtering (SPF)

Static Packet Filtering (SPF) is used like Stateful Packet Inspection( SPI) in firewalls and routing, but has limited functionality compared to the SPI method.

Static Packet Filtering (SPF) provides packet filtering, but it only filters individual data packets according to the system administrator 's rules. SPF filtering can apply to ports and IP addresses.

Static Packet Filtering can only look at single, individual data packets and cannot stop malicious attacks such as DoS attacks. As for the IP protocol, only individual data fields of the IP header can be viewed.