IP routing
TCP/IP architecture

An Internet environment results from the interconnection of physical networks by routers, whose name clearly indicates their function: from the address contained in the datagram, the router determines the best path at the moment of routing, thanks to a routing table that updates itself automatically. Each router is directly connected to two or more networks, while hosts can also be connected to one or more networks. Figure 7 shows a schematic representation of the transition from one subnetwork to another.

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