DNS Concepts

Question 1

DNS(Domain Name Service)

Answer 1

It resolves hostnames, such as www.google.co.uk, to IP addresses, such as 72.22.161.67.

Question 2

The DNS Namespace

Answer 2

Referrs to the hierarchy from .com’s at the top to subdomains or secondlevel domains associated with organizations or commercial companies.

Question 3

FQDN(fully qualified domain name)

Answer 3

The domain name, along with any subdomains, is called the FQDN

Question 4

Start of Authority (SOA)

Answer 4

Contains a record of information containing data on DNS zones and other DNS records.
A DNS zone is the part of a domain for which an individual DNS server is responsible. Each zone contains a single SOA record.

Question 5

Name Server (NS):.

Answer 5

Stores information that identifies the name servers in the domain that store information for that domain

Question 6

Canonical Name (CNAME)

Answer 6

Stores additional hostnames, or aliases, for hosts in the domain. A CNAME specifies an alias or nickname for a canonical hostname record in a domain name service (DNS) database.

Question 7

Pointer (PTR):

Answer 7

A pointer to the canonical name, which is used to perform a reverse DNS lookup, in which case the name is returned when the query originates with an IP address

Question 8

IPv6 Address (AAAA)

Answer 8

Stores information for IPv6 (128-bit) addresses. It is most commonly used to map hostnames to an IP address for a host.

Question 9

Mail Exchange (MX)

Answer 9

Stores information about where mail for the domain should be delivered.

Question 10

DDNS (dynamic DNS)

Answer 10

DNS Making changes in real time to hostnames, addresses, and related information.

DDNS in a computer can inform the DNS server of the new address.

Question 11

Windows Internet Name Service (WINS)

Answer 11

enables NetBIOS computer name to be used on the network rather than the IP address.

NetBIOS name resolution can be performed three ways:
1. The simplest way is to use a WINS server on the network that automatically performs the NetBIOS name resolution.
2. Use LMHOST file
3. Use broadcast to learn names
LMHOSTS file
Statically assign hostnames to IP addresses for use with netbios resolution.

Using an LMHOSTS file requires that you manually configure at least one text file with the entries. As you can imagine, this can be a time-consuming process, particularly if the systems on the network frequently change.