What device in a physical network is responsible for routing and forwarding packets?

In a physical network, the device that is responsible for routing and forwarding packets is indeed the router. Routers operate at Layer 3 of the OSI model, which is the network layer. Their primary function is to determine the best path for data packets to travel across different networks. This involves reading IP addresses and making decisions about where to send packets based on their destination.

In contrast, other devices like hubs and Layer 2 switches have different roles. A hub simply broadcasts incoming packets to all ports, thus not making any intelligent routing decisions. A Layer 2 switch, while capable of forwarding frames within the same local area network based on MAC addresses, does not perform functions such as packet routing between different networks. The physical server NIC (Network Interface Card) acts as the interface for a physical server to connect to the network but does not handle routing responsibilities.

Therefore, the router stands out as the device specifically designed for the task of routing and forwarding data packets across interconnected networks.