Sure! Below is an SEO-friendly HTML answer for the interview question about firewalls:

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Understanding Firewalls in Network Security

A firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules. It acts as a barrier between a trusted internal network and untrusted external networks, such as the internet, to prevent unauthorized access while allowing legitimate communication to pass through.

Firewalls are crucial for protecting a network from cyber threats, such as hackers, malware, and other malicious activities. By enforcing access control policies and inspecting network traffic, firewalls help to safeguard confidential information, maintain data integrity, and ensure the availability of network resources.

Overall, firewalls play a vital role in enhancing network security by acting as the first line of defense against cyber attacks and unauthorized access attempts.

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Focus Keyword: Firewall, Network Security