What is the primary function of a router?

The primary function of a router is to route data packets between different networks. This involves determining the most efficient path for data to travel from one network to another, which can encompass multiple networks and types of connections. Routers operate at the network layer of the OSI model, utilizing IP addresses to make forwarding decisions. By directing traffic based on the destination address contained in the data packets, routers help facilitate communication between devices that are part of separate networks, such as a local area network (LAN) and the internet.

The other options, while related to networking, do not encapsulate the main role of a router. Providing internet access to local devices is a function typically associated with modems or gateways, which can work in conjunction with routers. Storing network data over time pertains to functions more aligned with network-attached storage (NAS) or databases, not routers. Monitoring network security events often falls under the responsibilities of security appliances and software, such as firewalls or intrusion detection systems, rather than the primary function of routers.