Why do we need more than one IP address in a router, one for each interface? The
answer is that an interface is a connection of a router to a link. We will see that an
IP address defines a point in the Internet at which a device is connected. A router
with n interfaces is connected to the Internet at n points. This is the situation of a
house at the corner of a street with two gates; each gate has the address related to
the corresponding street