The subnetwork configured on the serial link between Router1 and Router2 overlaps with the subnetwork assigned to Ethernet0 of Router3.

An example is IPv4 addresses having network, subnetwork, and host portions.

Subnetwork

An internet domain is part of every network address, including web site addresses, email addresses. There are also subnetwork domains which are a subnetwork made up of a group of clients and servers under the control of one central security database..

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