Question

I have the knowledge to do subnetingmath, but I confused what device that is used to separate each subnet from other ones? who will route packets to the right subnetwork destination? If it is the router, do we need an interface per each subnetwork?

Answer 1

It is the router the one in charge of routing the packets to the right subnetworks. You need to assign each subnetwork to a different interface, but this does not necessarily mean physical interfaces. You can use virtual interfaces as well.

Here’s a Cisco link about them:

http://www.cisco.com/en/US/docs/ios/12_4/interface/configuration/guide/inb_virt.html