What is the primary function of a firewall in a network?

The primary function of a firewall in a network is to limit access based on Internet usage policy. A firewall acts as a barrier between a trusted internal network and untrusted external networks, such as the Internet. It monitors incoming and outgoing traffic and enforces predetermined security rules, which can include restrictions on what websites can be accessed or what types of data can enter or leave the network. This capability is essential for maintaining security, preventing unauthorized access, and ensuring that network resources are used in accordance with organizational policies.

While enhancing speed, monitoring productivity, and providing data encryption are important aspects of network management and security, they are not the main functions of a firewall. A firewall does not inherently increase Internet speed; it may even introduce latency due to the added processing. Monitoring employee productivity typically falls under different systems or tools designed for that purpose. Data encryption, on the other hand, protects data integrity and confidentiality but does not fulfill the primary role of controlling traffic flow and access, which is fundamental to what firewalls are designed to do.