Domain Name System (DNS)

Question 1

Internet service that translates domain names into IP addresses
DNS resolves IP addresses based on Fully Qualified Domain Names (FQDNs)

Answer 1

Domain Name System (DNS)

Question 2

Root domain

Answer 2

.

Question 3

.edu
.gov
.com
.org
.mil

Answer 3

Top-level Domain

Question 4

mit - (.edu), lsu - (.edu), google - (.com), nexgent - (.com), redcross -(.org), af army - (.mil)

Answer 4

Second-level Domain

Question 5

web (mit.edu), mail (google.com), www (google.com), learn (nexgent.com), givingday (redcross.org), www (af.mil), www (army.mil)

Answer 5

Host-level Domain

Question 6

Displays information about DNS names and their corresponding IP addresses, and it can be used to diagnose DNS servers

Answer 6

nslookup command

Question 7

The hostname combined with the host’s domain name.
Identifies the specific server or host at the domain
www.google.com, mail.google.com

Answer 7

FQDN (Full Qualified Domain Name)

Question 8

is a protocol (http, https, and ftp) that helps locate and find websites, files, documents on the internet
(ie: https://mail.google.com https://learn.nexgent.com)

Answer 8

URL (Uniform Resource Locator)

Question 9

A free to use DNS server on the public Internet (ie: 8.8.8.8 which is google)

ip config /all: will show DNS Servers

nslookup: will show website address and DNS server 8.8.8.8

Resolves public FQDNs to IP Addresses

Most ISPs have their own public DNS Server for their customers to use

Answer 9

Public DNS Server

Question 10

Windows Server, Linux BIND

Third party DNS software for most any operating system

Provides for internal hostname lookups within a private organization

Answer 10

Private DNS Server

Question 11

A mechanism for DNS servers to supply different results based on the source
For example, imagine an organization hosting their own website with public facing DNS

Answer 11

Split Horizon DNS (aka Split Brain)