Definition
A routing table is a data file stored in a router or a networked computer that lists the routes to particular network destinations. It essentially acts as a map, guiding network traffic to its intended location. When a data packet arrives at a router, the router examines the packet's destination IP address and consults its routing table to determine the best path for forwarding the packet. Understanding routing tables is crucial for network administrators and security professionals to ensure efficient data flow and troubleshoot connectivity issues. For instance, a network administrator might configure a routing table to prioritize traffic to a critical server over less important data. This differs from a MAC address table, which operates at a lower network layer and maps hardware addresses to physical ports. Routing tables are a fundamental concept tested on exams like CompTIA Network+ and CISSP.