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Concept of Firewall 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.

Firewalls can be implemented as software, hardware, or a combination of both. They examine data packets and determine whether to allow them through based on the established ruleset, which can include filtering by IP address, port, protocol, and other criteria.

By enforcing access policies and filtering network traffic, firewalls help prevent unauthorized access to the network, protect against cyber threats, and enhance overall network security. They are essential components of a layered security approach to safeguarding information and assets.

Network security engineers must configure and manage firewalls effectively to ensure they provide the necessary protection without impeding legitimate network traffic. Regular monitoring, updates, and adjustments to firewall rules are crucial for maintaining a secure network environment.

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