What is universal resolvability and why is it important to users?
Think of the phone system . . . when you dial a number, it rings at a particular location because there is a central numbering plan that ensures that each telephone number is unique. The DNS works in a similar way. If telephone numbers or domain names were not globally unique, phone calls or e-mail intended for one person might go to someone else with the same number or domain name. Without uniqueness, both systems would be unpredictable and therefore unreliable. Ensuring predictable results from any place on the Internet is called “universal resolvability.” It is a critical design feature of the DNS, one that makes the Internet the helpful, global resource that it is today. Without it, the same domain name might map to different Internet locations under different circumstances, which would only cause confusion.
