How a Firewall Protects Against Cyber Attacks
Firewall protects a company’s internal network from external access and cyber threats by scrutinizing incoming and outgoing data based on established security rules. Without a firewall, every computer within an enterprise would be accessible to any person connected to the Internet. Firewalls use a variety of security methods to scan and block cyberattacks, including packet filtering, stateful inspection, and circuit-level gateways.
Firewalls analyze information by reading the data packets that make up network traffic, looking at their defining characteristics like media, destination addresses, and contents, to determine whether to allow or deny them entry into the firewall. Packet filters evaluate each packet of information by comparing it against a database of predetermined criteria, ensuring that information entering the system matches certain standards.
A newer method, stateful inspection, examines each incoming or outgoing packet while keeping track of previous device and connection behavior. This offers more comprehensive protection by assessing each packet of information from a macroscopic perspective and assigning the data it contains to long-term device and user profiles.
Circuit-level gateways monitor specific protocols, like the Transfer Control Protocol (TCP), to verify that each stage of a transmission logically matches up. This offers greater protection and a higher level of performance than packet filters. However, if hackers find ways to manipulate TCP handshakes or other protocols, it’s possible for malicious traffic to bypass these types of firewalls.