What does a firewall do in a network?

A firewall in a network serves a critical role by filtering and monitoring incoming and outgoing network traffic. Its primary function is to enforce a set of rules that determine whether specific data packets should be allowed to enter or exit the network. This process helps protect the network from unauthorized access and various forms of cyber threats, such as malware and hacking attempts. By examining traffic against predefined security policies, the firewall can block suspicious activities and ensure that only legitimate communications are permitted.

This capability is essential for maintaining the integrity, confidentiality, and availability of data within the network. Firewalls can be implemented in both hardware and software forms, and their effectiveness contributes significantly to the overall security architecture of a network.

The other options describe functions that are not within the primary scope of a firewall. For example, enhancing wireless range pertains to network access points rather than security measures. Routing data between different IP networks is the function of routers, while connecting multiple LANs into a WAN is characteristic of specialized networking devices like WAN routers or multiplexers. These distinctions clarify the unique role that firewalls play in network security.