When a router does not have an entry in its routing table for the destination address, where will it send the packet?

When a router encounters a packet intended for a destination address that is not listed in its routing table, it will forward the packet to its default next router. This is an essential function of routing; a default route serves as a fallback option when specific routes are unavailable.

The default route acts like a catch-all that directs packets to a specified next hop when the router does not have a specific entry for the packet’s destination address. This typically points to another router that can take over the task of finding the destination, facilitating the continued movement of data through the network without interruption.

In larger networks, relying on a default route helps maintain efficiency and reduces the complexity of managing extensive routing tables, allowing routers to direct traffic effectively even when explicit paths to certain destinations are not known.