Which network device uses various protocols to connect networks through packet forwarding?

The correct answer is a router, which plays a crucial role in connecting multiple networks by forwarding packets between them. Routers analyze incoming data packets' destination IP addresses and determine the optimal path for sending them to the correct network. This involves using various protocols, such as Internet Protocol (IP) and Routing Information Protocol (RIP), to make informed forwarding decisions.

Routers are specifically designed to handle traffic between different networks and are critical for the functionality of the internet and internal company networks. By managing the flow of data efficiently, routers help to ensure that information is transmitted quickly and accurately across diverse network environments.

In contrast, other network devices serve different purposes. Hubs operate at a basic level, simply broadcasting incoming data packets to all connected devices without any intelligence or routing capability. Switches operate within a single network segment, directing packets based on MAC addresses and providing local traffic management, but they do not connect different networks. Gateways act as a "gateway" for data between disparate network architectures and can operate at various levels within the OSI model, but they do not specialize in packet forwarding across networks like routers do. Thus, routers are distinct in their purpose and functionality in connecting and managing data flow between different networks.