DNS Propagation Check

Provides free dns lookup service for checking domain name server records against a randomly selected list of DNS servers in different corners of the world.

DNSMap Articles What is DNS and how it works

Introduction

DNS stands for Domain Name System, and it is a significant part of the internet, which makes it possible for internet users to match the names of the websites they are looking for to the numbers that represent the addresses of these websites.
As a matter of fact, every device connected to the internet, be it your cell phones, laptops, tablets or websites has an Internet Protocol (IP) address, which is made up of numbers. Take for instance, your favorite website might have an IP address such as 45. 402. 220. 200 which, for a person, is somehow difficult to remember from time to time. However, if your favorite website’s name, for example, is www.goodfoods.com, it is easier for you to remember that. So, when you are accessing your favorite website, DNS syncs up its domain name with its corresponding IP address to make the website visible to you.
In practice, while you remember your favorite website’s domain name, your computer or other devices mainly recognize its unique IP address.

How DNS works

Outlined below are the ways DNS works to provide internet users with satisfactory experiences:
  • Your query: Technically, you send a query to the internet when you type www.goodfoods.com into the browser, asking the internet to help you find the website. A query is considered to be a definite question which requests that the website’s domain name be matched with its designated IP address. Considering the Internet Architecture, your query will have to go through some servers before your requested website can pop up. The first server that will interact or engage with your query is called the recursive resolver, and this kind of server can be operated by your wireless carrier, Internet Service Provider (ISP), or a third-party provider. The recursive resolver will then go ahead querying other servers to find answer to your initial query, which is “what is the IP address of www.goodfoods.com?”
  • The Root Servers: The very first type of DNS server that recursive resolver gets in touch with is referred to as a Root Server. There are several Root Servers all over the world, and each of them has adequate DNS information about Top Level Domains like .com. In order to provide answer to your initial query, the recursive resolver requests that the Root Server provide the necessary information about .com. There are thousands of servers that support the root around the world, but DNS makes sure that your query is sent to the root server nearest to you.
    Listed below are the 13 authorities that operate the known 13 DNS Root Zones’ Servers:
    • VeriSign, Inc. (198.41.0.4, 2001:503:ba3e::2:30)
    • University of Southern California (ISI)
    • Cogent Communications
    • University of Maryland
    • NASA (Ames Research Center)
    • Internet Systems Consortium, Inc.
    • US Department of Defense (NIC)
    • US Army (Research Lab)
    • Netnod
    • VeriSign, Inc (192.58.128.30.2001:503:c27::2:30)
    • RIPE NCC
    • ICANN
    • WIDE Project
  • The Top Level Domain Name Server: At this stage, each Top Level Domain (TLD) DNS name server stores the IP address information for second level domains (goodfoods.com) within the top level domain (.com). As your query gets to the Top Level Domain Server, the TLD server promptly answers with the IP address of the domain’s name server, which will then lead to the next phase of the process.
  • The Domain’s Name Server: Here, the recursive resolver forwards the query to the Domain’s Name Server. The DNS server recognizes the IP address for the full domain name, www.goodfoods.com and that answer is sent back to the recursive resolver.
  • Your Favorite Website Will Show Up: Now that the recursive resolver has discovered the IP address of the website in your query, it will inform the browser the website’s IP address. And then, your browser will send a request to the website to retrieve the website’s content using the IP address is has just learned from the recursive resolver. Although, these procedures appear to be lengthy; however, they can happen within a tenth of a second. It is so fast that the entire process can occur before a blink of an eye.