Without a way to accurately identify how to reach devices, all network (and Internet) communication would simply collapse. My computer might be physically connected to yours (and to a million others), but expecting my e-mail to magically find its destination without a routable address is like throwing a bottle with a message inside into the ocean and expecting it to arrive on the kitchen table of a friend who lives ten thousand miles away. Within five minutes.
Fundamentals of Internet Protocols
Broadly speaking, modern networks rely on three conventions to solve the ...
