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Cybersecurity tax on DNS servers are one of the most significant threats to Internet security today

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and it is important to understand how it works.

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DNS domain name server is used to resolve names to IP addresses.

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When you type google.com in your web browser.

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Behind the scenes your computer is doing a DNS look up to find the IP address of the Web site that you're

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trying to connect to.

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You can almost compare it to saving a phone number as a contact in your phone.

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So when you want to call someone on your cell phone instead of actually typing in their actual phone

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number every time you just pull up your contact name and then hit call and it resolves the contact name

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to the phone number that you have store in your phone contacts and in the background you're actually

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calling that phone number and not the contact name.

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Just like with networking even though in our web browser we're typing in Google dot com we're actually

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in the background connecting to Google dot com IP address.

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So why not go directly to the IP address.

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You may ask yourself well for users it is a lot easier to remember a name like Google dot com instead

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of the actual IP address.

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DNS is built around a hierarchy of servers at the top level is the root servers that own anything once

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a root server receives the request it sends the response back to direct the requester to the right server

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based on a top level domain.

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You need to reach like dot com or dot org.

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Then the top level domain server will direct the requester to the owner of the domain name like Google

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for example.

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Here's what a DNS request for Google dot com would look like.

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Within the hierarchy of domain name servers.

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So you can see an example of a DNS request in my terminal here.

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I'm going to ping being dot com and in the background I have wireshark running and it's filtering to

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only capture packets that match DNS server requests.

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So when I ping this my computer should sign a DNS look up requests to my DNS server.

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Ok so you can see that my computer sent a DNS request to my DNS server at 10.0 up 3.3.

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And then my DNS server responded with the IP address for the domain name that I request.