What is DNS Propagation all About?
When you set up your website with a web hosting company and go through the domain registration process, they will tell you that your new domain name will be done "propagating" after a period of time between 24 hours and 96 hours. Don't worry if you don't know what this means - a lot of people don't. Domain name propagation is actually fairly simple to understand. The propagation time for your domain name is the time between you registering your domain name and the time people can actually type it into their browser and be taken to your site.
A lot of behind the scenes work takes place during the propagation period of domain registration. It's something that all new websites have to go through. During this time, your new domain name and its IP address are linked up with each other on DNS servers all over the web. Your IP address is a series of numbers separated by decimal point that is assigned to your website on devices using the internet protocol for communication. It identifies your host, and your site's address on your host's server. Even though IP addresses are stored in the form of binary numbers, you'll see them displayed not as a series of zeroes and ones, but as what look like ordinary numbers, such as 999.88.77.666.
http://en.wikipedia.org/wiki/IP_address - cite_note-rfc791-1
Propagation is a process of your web hosting provider "introducing" you as the new guy on the network and letting all the other servers know that your domain name is hooked up with the particular string of numbers that makes up your IP address. Your web hosting company creates what is called a Master DNS record in their Domain Name Server database. As you can probably guess, DNS stands for Domain Name Server. This master DNS record tells the rest of the web that your host's DNS server is the master keeper of information about your domain.
For this to happen expediently, the information mapping your domain name to your IP address has to propagate throughout DNS tables on the web. This is what takes place during domain registration. The information in the DNS tables include the IP address, the nameserver (a computer whose job it is to translate domain names into appropriate IP addresses and IP addresses into domain names), information about the host, your web hosting provider's hardware and software information, and other necessary fields. DNS tables have to be updated to include the information about your site. Normally, this updating occurs once a day. If you've just missed a particular DNS server's update, it will be another 24 hours before your next chance to be included in their update.
When propagation has successfully taken place, If someone wants to find your website, they type its name into their web browser. From there, the browser goes to the registration database to find out who the DNS authority is for your site. Once the browser finds this, it goes through the provider's DNS servers to match up the domain name to a specific IP address. When it finds your IP address, it can display your website for the person who has typed your domain name into their browser.
The whole process of updating DNS records makes web surfing faster. Each web hosting provider has their own copy of the master records, and reads from it rather than looking up the IP address on the internet each time someone wants to see your website. This process makes it faster for browsers to get an IP address when they look up domain names, and keeps your web host's information local rather than web-wide, therefore reducing web traffic to just the necessities.
If you should transfer your domain name, go through domain registration for another domain name to be attached to your site, or change your nameserver, propagation will have to take place again. The propagation process is usually done within 24 to 48 hours, but you should allow up to 96 hours to take place because there's no real standard for how often DNS servers update.
While the propagation is taking place, you can still access your new site so that you can set it up the way you want it. Once propagation is complete, the translation of your domain name into your IP address takes place automatically whenever someone types your domain name into their browser so that your web hosting provider can quickly retrieve your website based on its IP address.
