DNS is mostly a directory service. Millions of people and computers use one or more directories every day. Currently, so many directories exist in our world that they have become almost transparent to casual observers. You could say it's a directory kind of world out there and DNS remains a big part of it for people who use the Internet regardless of the device.

In the old days, people often referred to directories as databases and technically they were right. Directories and databases share many characteristics such as the storing of information and the ability to rapidly search through that data. Think of how many times you use your cell phone as a database for personal contacts. In fact, your cell uses its address book as a directory to rapidly find and dial people's telephone numbers.

Directories also differ from databases because people tend to read the contents of a directory far more than they write to it. Directories don't require support for transactions, indexes, triggers and storing of binary objects. Directories provide information people and programs need to perform some activity and directories provide the information quickly.

You might wonder why system administrators have to know the inner workings of DNS. It's a directory, right?

Full Story.