What is DNS and which port number is used by DNS?

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1. What is DNS and which port number is used by DNS?

'You'll connect to the Wikipedia server through port 80.'
used to resolve human-readable hostnames like www.intenseschool.com into machine-readable IP addresses like 69.143.201.22. DNS servers use UDP port 53 but DNS queries can also use TCP port 53 if the former is not accepted
For the IP address that most people are familiar with (IPv4), there are 4 sets (octets) of numbers, each with values of up to 255. You likely have run into this when troubleshooting a router or a DHCP server, when they are giving out addresses in a particular range- usually 192.x or 10.x in the case of a home or commercial network. IP classes are primarily differentiated by the number of potential hosts they can support on a single network. The more networks supported on a given IP class, the fewer addresses are available for each network. Class A networks run up to 127.x.x.x (with the exception of 127.0.0.1, which is reserved for loopback or localhost connections). These networks are usually reserved for the very largest of customers, or some of the original members of the Internet and xkcd has an excellent map (albeit a bit dated) located here showing who officially owns what. Class B (128.x to 191.x) and Class C (192.x to 223.x) networks are much more fuzzy at the top level about who officially owns them. Class C addresses are primarily reserved for in-house networks which is as we mentioned above why so many different manufacturers use 192.x as their default setting. Class D and E are reserved for special uses and normally are not required knowledge.
THE admin, but in a Linux environment it is important to remember that unlike in a Windows environment, you spend very little time in a 'privileged' mode. Many Windows programs over the years have required that the user be a local admin in order to function properly and have caused huge security issues as a result. This has changed some over the years, but it can still be difficult to remove all of the programs asking for top level permissions. A Linux user remains as a standard user nearly all the time, and only when necessary do they change their permissions to that of root or the superuser (su). sudo (literally- superuser do ...) is the main way used to run one-off commands as root, or it is also possible to temporarily have a root-level bash prompt. UAC (User Account Control) is similar in theme to sudo, and like Windows Firewall can be a pain in the neck but it does do a lot of good. Both programs allow the user to engage higher-level permissions without having to log out of their current user session- a massive time saver.

What is DNS and which port number is used by DNS?

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What is DNS and which port number is used by DNS?

❤ If you liked Fatskills, consider supporting us by checking out The Life Manuals You Never Got.

About | Explore | User Guide | Topics | Subjects | Doubt Solver | Career Aptitude Test | Answers | Free Tools | What Should We Know? Privacy | Terms |

Without work one finishes nothing. - Ralph Waldo Emerson© 2026 Fatskills.com

All trademarks, logos and brand names are the property of their respective owners. All company, product and service names used in this website are for identification purposes only. Use of these names, trademarks and brands does not imply endorsement.

About | Explore | User Guide | Topics | Subjects | Doubt Solver | Career Aptitude Test | Answers | Free Tools | What Should We Know?
Privacy | Terms |

Without work one finishes nothing. - Ralph Waldo Emerson
© 2026 Fatskills.com