Please Whitelist This Site? I know everyone hates ads. But please understand that I am providing premium content for free that takes hundreds of hours of time to research and write. I don't want to go to a pay-only model like some sites, but when more and more people block ads, I end up working for free. And I have a family to support, just like you. :) If you like The TCP/IP Guide, please consider the download version. It's priced very economically and you can read all of it in a convenient format without ads. If you want to use this site for free, I'd be grateful if you could add the site to the whitelist for Adblock. To do so, just open the Adblock menu and select "Disable on tcpipguide.com". Or go to the Tools menu and select "Adblock Plus Preferences...". Then click "Add Filter..." at the bottom, and add this string: "@@||tcpipguide.com^$document". Then just click OK. Thanks for your understanding! Sincerely, Charles Kozierok Author and Publisher, The TCP/IP Guide

NOTE: Using software to mass-download the site degrades the server and is prohibited. If you want to read The TCP/IP Guide offline, please consider licensing it. Thank you.

The TCP/IP Guide  9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)       9  Name Systems and TCP/IP Name Registration and Name Resolution            9  TCP/IP Name Systems: Host Tables and Domain Name System (DNS)                 9  TCP/IP Domain Name System (DNS)

TCP/IP Domain Name System (DNS) 1 DNS Overview, History and Standards

Most of us know that it's a lot easier to be a critic than a creator. It was easy to tell that the host table name system used on the fledgling TCP/IP Internet was not going to serve it going into the future, but finding a solution to this problem was much more difficult. The main reason the host table system was insufficient was that it was too simple, and this meant that its replacement, the Domain Name System (DNS), had to be considerably more sophisticated. Naturally, this made DNS more difficult to design, and also means we have to devote more energy to understanding how it works.

As I like to do with the explanation of most of the complex systems and protocols in this Guide, I begin in this section with background information and an introduction to TCP/IP DNS. I start by providing an overview of DNS's development, history and standards, continuing the history begun in the overall look at TCP/IP name systems. I discuss the design goals and objectives of the creators of DNS, to help you understand better what its designers were trying to do. I then talk about the main components of DNS and the functions it performs, relating these to the basic functions explained in the overview section on name systems.

TCP/IP Domain Name System (DNS) 1 DNS Overview, History and Standards