Firewalls are used to screen and avoid block the threat posed by unwanted data or files that could want to penetrate into a system. Hence, the kind of firewall described is packet filtering firewall.
- Packet filtering firewall describes a network security protocol which examines individual data packets entering into a system.
- Each data packet is screened based on established principles and protocols, with only those who meet the defined requirement allowed to reach their destination while others are dropped.
Hence, the missing phrase is packet filtering firewall.
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