What is DNS, and why should I care what it is?
Requested and Answered by Gene Amtower [pcbgene] on 09-Mar-2009 17:12 (7063 reads)
DNS stands for Domain Name System, and it is an important component of how we use the Internet today. So, just how important is it?
Well, whenever you browse the Internet through a web browser, you take advantage of what DNS provides to us. Essentially, DNS performs a translation between what you see/type in a web address (i.e. www.pcbackuponline.com) and how devices on the Internet actually communicate between each other.
All connections to the Internet are associated with a specific numeric address on the World Wide Web, sort of like a street address but without a street name. (Imagine if you had to find your buddy's house across town by locating house number 12,184,442 instead of 1234 Main Street!) This numeric address is called an Internet Protocol address - or simply IP address. Accessing any content on the Internet requires the associated IP address of the content's source rather than the name you enter in your browser.
It would be terrible if we had to remember a bunch of numbers to access our favorite web content, so DNS was created to allow Internet content to be found by name rather than by IP address. When you enter a web site address by its name, your computer accesses the closest DNS server to ask for the numeric address that matches that named address. DNS servers know how to communicate between themselves to find a DNS server that can answer the question, and the IP address that matches the named address gets passed back to your computer once one is found that has the answer. (How DNS servers know which DNS server to ask next is more complicated than we'll get into here, but trust me when I say that they know how to find the answer through the smallest number of DNS servers! You don't want to get passed around the Internet just looking for that one IP address.)
Once your computer has successfully translated the named address into an IP address, then (and only then) can it send the original request to the identified IP address, with the answer finally making its way back to your screen. Occasionally, a computer or communication problem results in no available DNS servers to perform this critical name-to-number translation, and then you get an error that no DNS server was found. If you've ever seen an error message in your web browser mentioning a problem with DNS instead of the content you expected, then you know how important DNS is to us.
Without the DNS system, using the Internet would be a painful experience rather than an enjoyable pastime for so many of us.
Well, whenever you browse the Internet through a web browser, you take advantage of what DNS provides to us. Essentially, DNS performs a translation between what you see/type in a web address (i.e. www.pcbackuponline.com) and how devices on the Internet actually communicate between each other.
All connections to the Internet are associated with a specific numeric address on the World Wide Web, sort of like a street address but without a street name. (Imagine if you had to find your buddy's house across town by locating house number 12,184,442 instead of 1234 Main Street!) This numeric address is called an Internet Protocol address - or simply IP address. Accessing any content on the Internet requires the associated IP address of the content's source rather than the name you enter in your browser.
It would be terrible if we had to remember a bunch of numbers to access our favorite web content, so DNS was created to allow Internet content to be found by name rather than by IP address. When you enter a web site address by its name, your computer accesses the closest DNS server to ask for the numeric address that matches that named address. DNS servers know how to communicate between themselves to find a DNS server that can answer the question, and the IP address that matches the named address gets passed back to your computer once one is found that has the answer. (How DNS servers know which DNS server to ask next is more complicated than we'll get into here, but trust me when I say that they know how to find the answer through the smallest number of DNS servers! You don't want to get passed around the Internet just looking for that one IP address.)
Once your computer has successfully translated the named address into an IP address, then (and only then) can it send the original request to the identified IP address, with the answer finally making its way back to your screen. Occasionally, a computer or communication problem results in no available DNS servers to perform this critical name-to-number translation, and then you get an error that no DNS server was found. If you've ever seen an error message in your web browser mentioning a problem with DNS instead of the content you expected, then you know how important DNS is to us.
Without the DNS system, using the Internet would be a painful experience rather than an enjoyable pastime for so many of us.
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