OK, in the last lecture, we had a brief introduction to the DNS server not to complete unqualified
domain name service names that will be used to search and submit DNS queries or declined for resolution.
You must have a list of DNS suffixes that can be appended to these days DNS names for DCP Glines.
This can be said about assigning the DNS domain name option and providing a single DNS suffix for the
client to append and use in searches.
Now, in this lecture, we're going to talk about the DNS record type's.
Address mapping, record it now host is called an area record, and what it gives is it gives you the
IP address of a domain or a host in IP version six.
It is called a quad or four times a record.
Now, your earlier records.
So these records.
Let me take the pointer.
Yeah.
So these records resolve the host names to IP addresses, but what happens if you know the IP address
and then you want to hostname?
Well, there is a record for it too.
That is a pointer record which formulates back or points back to the name now.
Canonical name record.
That is the C name record.
Now the C name record can be used as an alias to a hostname or another hostname.
When a DNS client requests a record that contains a canonical name which points to another host name,
the DNS resolution process is repeated with a new host.
So basically C name is used to, you know, point to another host name and then this process continues.
Well, finally, the new hostname is the next is the main exchange, a record that is the imex record
of the Amex record points to the mail exchanger for a particular host.
Now, DNS is structured so that you can actually specify several e-mail exchanges for one host.
So basically the Amex record is involved in sending and receiving e-mails through a particular server
name server records.
That is, the NSA records, not NSA records, specifies that a DNS zone such as, let's say, Google
dot com is delegated to a specific authoritative name server and it provides the address of the name
server.
So it is authoritative name server, authoritative name.
So it's basically, let's say www.youtube.com and Google is the authoritative name server.
Dot com is the root level server.
We have seen the different route domains or the different dot com designations in the last lecture.
And I have told you that the domains that is top level domain or the root level domains and dot com
is one of the root level domain and therefore authoritative names.
Server is Google.
Reverse lookup point records allows a DNS resolver to provide an IP address and receive a host name.
So what what area code does basically?
So what area code does?
What this record does is basically to give the name and it will return an IP address.
OK, it will return an IP address.
But in case of this reverse lookup pointer, you give an IP address.
So it allows the DNS resolved to provide an IP address and receive a hostname.
So it's a voiceover subprocess.
The next is certificate record, that is a solid record.
Now the certificate of record stores and certificates, for example, Bishkek's that is public infrastructure,
Speccy, BGP and so on.
Now, when you go to w w w dot Google dot com in the browser in November, suppose this is of a bar
and here is w w w dot com.
There is a small lockyear here.
OK, if the certificate or if this website is protected then you click here.
There is a box which tells you that certificate is stored.
Now where is the certificate or the certificate is actually stored in the certificate record.
OK, next is service location.
That is the S of record.
A service record is a generalized service location record which is used for new protocols instead of
creating protocol specific records.
Then is that the extra costs, the extra guards are used to provide authentication of mail sent and
received by the same e-mail system.
It basically works on the sender.
Is your policy, for example, if any one of you has created a website or they won't have the host the
website, they might be knowing that when you want to verify your website, you have to add the structure
in place and you have to verify that the extra record after a certain point from the original server.
And then if that is verified by the mail exchanger, then you are allowed to send and receive third
party emails on your.
The next is the esoterica that is the start of authority now, this record appears at the beginning
of the DNA on file, and it indicates the authoritative name server, for example, Google for the current
DNA.
It also provides the contact details for the domain administrator domain serial number and information
on how frequently DNS information for the zone should be refreshed.
Now, in the next lecture, I'm going to discuss about the different types of business and external
internal DNS, but before going ahead, we are going to use a DNS dumpster that is dumpster practical,
where you'll find how to calculate or how to find out the information from a domain name.
So it's a great practical and I recommend you to not skip the spectacle.
I will see you in the next lecture.