Q Assume we have an isolated link not connected to any other

Q Assume we have an isolated link (not connected to any other link) such as a private network in a company. Do we still need addresses in both network layer and data link layer? Explain.

Solution:

In the above case each router or host should have the knowledge of the link-layer address to which it belongs. Address resolution protocol is used to decide about the address of the destination link-layer.