What device can inspect IP data to determine its forwarding destination?

A router is designed to inspect IP data packets and determine their forwarding destination based on the information contained in the packet headers. When a packet arrives at a router, it reads the destination IP address and consults its routing table to decide the best path for the packet to reach its destination. This ability to analyze and direct traffic at the network layer (Layer 3 of the OSI model) is essential for efficient communication across interconnected networks, such as the Internet.

In contrast, a switch operates primarily at the data link layer (Layer 2) and uses MAC addresses to direct traffic within a local area network (LAN) rather than IP addresses. A hub simply broadcasts incoming data packets to all ports and does not perform any filtering or inspection for forwarding decisions. Meanwhile, a modem acts as a bridge between the local network and the internet by modulating and demodulating signals but does not perform the IP packet inspection necessary for routing. Thus, the role of determining forwarding destinations based on IP data is specifically the function of a router.