Which device performs the function of determining the path that messages should take through internetworks?

• A. a router
• B. a firewall
• C. a web server
• D. a DSL modem

Answer: (A)

Routing devices decide where packets should go next by analyzing the destination IP address and consulting a routing table to choose the best next hop toward the destination. This capability lets a router move data across multiple networks, from your local LAN through potentially many interconnections to reach a remote host. Routers also share routing information with other routers using routing protocols (like OSPF, EIGRP, or BGP) to update paths and metrics such as hop count or link speed, helping to determine the most efficient route through an internetwork. In contrast, a firewall focuses on enforcing security rules, a web server provides content, and a DSL modem mainly handles the connection between your local network and your ISP without making multi-network routing decisions.