What is the purpose of firewalls in network security?

Firewalls play a critical role in network security by monitoring and controlling incoming and outgoing traffic to safeguard the network from unauthorized access and potential threats. They act as a barrier between a trusted internal network and untrusted external networks, typically the internet. By enforcing predefined security rules, firewalls can allow or block traffic based on specific criteria such as IP addresses, protocols, ports, and even the content of the communications.

This monitoring capability is vital for detecting and preventing unauthorized access attempts, which could lead to data breaches or other malicious activities. Firewalls can also help in maintaining the integrity and confidentiality of data as it moves through the network by filtering out potentially harmful data packets.

In contrast, increasing the speed of the network, providing internet access, or storing sensitive data securely are not primary functions of firewalls. While enhancing performance or ensuring storage security may be related aspects of overall network management or security, they do not define the core purpose of a firewall in protecting the network.