Friday, October 29, 2010

Introduction to DNS

DNS (Domain Name System) is what the internet without any of our favorite sites would work, we wouldnt be able to check our e-mail, check out our facebook, in fact, 99% of their Internet communications would not work without DNS. So what exactly is it? Well, basically it converts a DNS domain name (eg google.com) in a machine readable IP address.

What is an IP address? - Well its very important that you understand what an ipaddress is if you're going to understand how DNS works. Essentially any device that communicates over the Internet is using an IP address. This is a 4 block number ranging from 0 to 255 for each block, for example, 24.50.10.99 is an IP address. Will not go into specific details here, but every car that wants to communicate on the Internet, use this address to verify the identity itself. The router does not understand domain names, only understand the IP addresses so it is essentialone that converts a domain name.

Note: The above I refer to IPv4 and IPv6 is not

So what do DNS? - Every time you type a URL in the web browser of your computer should find the IP address of the domain, but does so by performing a DNS lookup DNS. Your computer will query the server for its primary IP address (you can check your primary DNS server by going to the command prompt and type ipconfig / all)

So fargood right? However, a basic DNS query is usually a host machine (for example) put the primary DNS server for the IP address for google.com, the DNS server domain and return the product to your machine knows now that Google has, or at least the IP address that the information they need to communicate.

The hierarchy of DNS - Unfortunately, not all DNS serverseach result, a full DNS database is huge, just think how many millions and millions of websites out there! This is because there are more links in the chain of DNS. At the top of the chain are what's called root servers, which contain all the answers, but each domain name that is globally accessible to learn. However, the computer is not in this place as your primary DNS server does not know the answer next to it will ask its server in the chain, this is typically a DNS server. If the server does not know the answer, asks the next in the chain will continue to happen until a root server is required that the extension will always answer.

To speed things up a bit 'now, most of the DNS server has a cache or temporary storage of DNS records, which usually last about 24, but save the root servers are constantly questioned> DNS server before you know the answer.

So there you have it, a basic course for DNS, as I said is really a vast subject and we have just scratched the surface here, but now we know what DNS and why it is so important.

Related : Flip Camcorders Store. LOWER Prices in Same Item Cool Phones Review Transcend 8 GB SDHC Class 6 Store

No comments:

Post a Comment