Routing
Routing is a process that takes place at the Network Layer (Layer 3) of the OSI model. It is the process by which a router will decide out of which interface it will send a packet based on its destination address.
When a router receives a packet, it will examine the destination IP address and compare it with the entries it has in the Routing Table. Based on those entries, it will forward the packet out of the appropriate egress interface.
Routing is a fundamental operation of the IPv4 and IPv6 protocols and enables end to end (host to host) communication.
Links
https://networklessons.com/cisco/ccna-200-301/introduction-to-routers-and-routing
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