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The ABCs of TCP/IP
represents a method of conserving IP network addresses and is described and
discussed in detail later in this section.
Overview
Although a host is normally associated with a distinct IP address, in actuality
IP addresses are used by the Internet Protocol to identify distinct device
interfaces. That is, each interface on a device has a unique IP address. This
explains how a router with multiple interfaces can receive communications
addressed to the device on different router ports connected to LANs and
WANs. Devices such as hosts, routers, and gateways can have either single
or multiple interfaces. When the latter situation occurs, ...