Original subtitles

Hi, guys, and welcome back to another lecture of the namespace section.

We haven't really talked about the famous roots a number of times so far.

First in the domain name for a lecture and then with regards to its position into the industry.

But what exactly is this roots in real terms?

Going back to the beginning of the course, we discussed that the primary purpose of VNS is to translate

domain names to IP addresses with the ultimate goal of accessing a website.

The action of converting a domain name into an IP address is referred to as name resolution and name.

Resolution is a process that starts with a query that goes somewhere.

The first recipient of our request is one of the root servers, which sits at the top of the hierarchical

the industry, as discussed in the previous video.

Upon receiving a query to resolve a specific name, the root service job is to pass back a referral

for a top-level domain name server based on the till the extension of the domain name being requested.

For example, if I were to browse to W WW Dot Yahoo.com, my DNS requests would be received by a root

server, which would spark a referral with a common name server so that a query is sent there next.

For further processing.

Thanks to the information received by the root server, we cannot proceed with a resolution process

which we will go into more detail later on the course, it is worth noting that the procedure involved

here is a bit more complicated than that, with a few more systems and technologies working in the background

before a root server receives a DNS request.

Hence, the reason why those square brackets with the included dots are also present in the slide.

The main point to understand and remember at this stage is that root servers are the first component

of the DNS tree that receive a DNS query, and they contribute to the resolution process by providing

a referral to a top-level domain name.

Server A corresponds to the top-level domain extension of the domain name being requested.

There are 13 root name servers, each of which is named with the letters A to M.

And more information about the root name servers can be found at Page Call on forward slash forward

slash root hyphen service org.

If we browser that website, we can get more information about all those 13 root servers listed here

from a to a.m. that operators, meaning the organizations are responsible for them, the locations they

reside in, their IP addresses, IP six addresses and autonomous system numbers, which are related

to the BGP protocol, which is outside the scope of this course.

If you wish to get more information about, say, Server A., you just need to click on its home page.

Which will take you to another page giving you more data about the history of that root server, system

metrics, raw data and much more.

Because of the important role they play in the DNS resolution process, root servers are one of the

most critical infrastructures in the internet.

And though the number 13, there are multiple copies of each one at over 130 locations all over the

world, hosted in multiple secure sites with high bandwidth access to handle the traffic load, with

938 root servers being in operation worldwide as of February the 20th 2019.

That's all you need to know about room service at this point, guys.

And if the concept of the route is not totally demystified, yes, don't worry, it would make much

more sense when we get to the section of name resolution.

Thank you for watching, and I would see you in the next one.