What is the function of a firewall in a network?

The function of a firewall in a network is primarily to inspect and control traffic entering or leaving the network. Firewalls act as a security barrier between trusted internal networks and untrusted external networks, such as the internet. They monitor incoming and outgoing data packets based on predetermined security rules and policies. This helps in blocking unauthorized access, filtering traffic based on specific criteria, and protecting the network from various threats, such as malware, hacking attempts, and other malicious activities.

This traffic inspection and control capability make firewalls essential components of network security architectures, as they help maintain the integrity, confidentiality, and availability of resources and data within the network. By evaluating traffic against their rulesets, firewalls can permit or deny access to resources, providing a first line of defense against cyber threats.