Original subtitles

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DNS or domain name system service

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so on our previous lessons of course we mentioned the IP which is the Internet Protocol.

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So a computer must have an IP to communicate over network so if it cannot receive an IP it cannot exchange

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data over the network.

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So you know that in order to communicate with one computer another computer will need to know the IP

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address of the computers that it wants to communicate with.

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It's gonna be difficult for all computers that will be contacted to remember a numerical IP address

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value therefore the DNS or domain name system protocol has emerged the DNS protocol matches computer

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threads to their names.

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So it makes Name IP matching possible.

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This way we can only access a site that we know the name of.

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Now there are servers that provide a DNS service and these are called DNS servers so the DNS protocol

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uses the UDP DCP port 53 and it computer automatically receives a DNS server address when it receives

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an IP however we can also manually define this address so if we want to communicate with a computer

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without a defined DNS over the network we're going to need to know the IP address of each computer or

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web address that we want to reach.

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Otherwise communication is going to take place so the DNS protocol works on our computer as follows.

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Let's suppose that we want to access dub dub dub dub Google dot com.

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Who would ever want to do that.

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Anyway when we type it into our web browser and click on enter the web browser forwards the request

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to the network card and network card then receives a request and forwards a request to the DNS server

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defined in the IP setting and the DNS server transmits the IP information from dub dub dub Google dot

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com to the requesting computer and the computer receives a request to the network layer and transmits

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it to the web browser.

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And the web browser shows us our request so different commands are used on Linux and Windows computers

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to view DNS setting to view it on Windows computer.

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Run run is written in command IP config.

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All is entered on the incoming screen and then the address that you see here is a DNS server address.

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Linux

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is a bit different open up terminal type leaf pad slash ATC slash resolved dot conf at the end of the

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command prompt enter the DNS server address of the next computer computers displayed on the screen and

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map and scanning so when we scan with then map it attempts to resolve the DNS name of each IP address

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it scans by default so for this purpose it performs an IP name analysis on the DNS server for each IP

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address.

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So in this case depending on the DNS server name IP analysis may take a little time and this increases

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the scanning time of course.

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So to prevent this when we scan with an parrot and map scans without DNS resolution and map our scanning

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so when we scan within map the names of the target servers can always give us some clues.

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So I means in this case the IP name analysis is required for this.

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We'll use the r parameter and then this parameter requires DNS resolution for each IP address.