What is the primary purpose of using a router in a network?

The primary purpose of using a router in a network is to route packets between different networks. Routers are specialized devices that manage traffic between diverse networks by analyzing the destination address of data packets and determining the best path for them to reach their intended location. This functionality is crucial in enabling communication across the internet and differentiating the roles of distinct networks, such as local area networks (LANs) and wide area networks (WANs).

When used in conjunction with other network devices, routers also facilitate broader connectivity, allowing users on one network to access resources on another network, such as the internet. They make decisions based on routing tables and protocols, ensuring efficient data delivery and reducing congestion on the network.

The other options do not accurately capture the primary function of a router. While routers can have certain capabilities like acting in a firewall capacity or assisting in data flow management, their foundational role is centered around routing packets strategically across networks.