What is the purpose of a firewall in a network security framework?

The purpose of a firewall in a network security framework is to filter incoming and outgoing traffic based on predetermined security rules. Firewalls serve as a barrier between a trusted internal network and untrusted external networks, such as the internet. By establishing a set of security rules, firewalls can allow or block traffic based on specific criteria, such as IP addresses, ports, or protocols. This capability is essential for protecting sensitive information from unauthorized access and ensuring that malicious traffic does not penetrate the network.

The functionality of a firewall is foundational in maintaining network integrity, preventing unauthorized access, and enforcing security policies. It does not encrypt data, monitor employee productivity, or detect/remove malware directly; these tasks are typically handled by other security tools or systems within a comprehensive cybersecurity strategy. Therefore, the role of a firewall is focused on controlling communication flows to safeguard network resources effectively.