Here are some frequently asked questions about domain names. A glossary of terms sits at the bottom of the page.
· For information
on registering a domain name with MYNIC, please refer to the FAQ
- About MYNIC
· For information on personal domain names, please refer to the FAQ
- About Personal Domain Names
· For information on Resellers, please refer to the FAQ
- About Resellers
What is a domain name?
Why does a domain name look the way it does?
What is the difference between a domain name and a URL?
What is the difference between a domain name and an IP address?
How are domain names translated into IP addresses?
Why are name servers required?
What’s a primary name server?
What’s a secondary name server?
What is a domain name?
A domain name is simply a textual address by which anyone can find your host machine on the Internet.
Why does a domain name look the way it does?
A domain name always contains a few components, i.e.labels, which are separated by a dot (period), thus: www.abc.com.my
The structure of a domain name conforms to the DNS Internet naming hierarchy which follows a tree structure. This structure allows computers to find each other on the Internet (see How are domain names translated into IP addresses? below).
At the very top of this hierarchy is the root (which does not appear in the domain name). The next level down of this hierarchy is the top level domain (TLD), the one after that being the second-level domain, and so on.
The TLD is what appears at the far right end of a domain name. In the example above, the TLD is .my. TLDs come either as country codes domain names like .uk, and .jp, or generic top-level domain names like .com, .net, or .gov.
What is the difference between a domain name and a URL?
URL stands for Uniform Resource Locator, a form of address that specifies the location of an object, usually a webpage or a website on the Internet. Here are some examples of URLs:
A URL contains three parts, i.e.
Therefore, a domain name is used in a URL. When you use the web
or send an e-mail message, a domain name is used. For example,
What is the difference between a domain name and an IP address?
They are different forms of Internet addresses.
An IP address or network address is a numeric form of address that identifies every machine on the Internet. Therefore, every machine has a unique IP address. For example, the IP address of the abc company website could be 192.228.180.200.
A domain name is a textual form of address that is easier for humans to remember than the string of numbers that makes up an IP address. For example, the domain name of that same abc company could be http://www.abc.com.my. However, this domain name could have more than one IP address.
When you browse a particular web site, it is actually the IP address that determines the successful communication between your computer and the website. IP addresses could be said to be computer-friendly, while domain names are human user-friendly.
How are domain names translated into IP addresses?
The technology that allows this to happen is called Domain Name System (DNS) technology. This provides the mapping between user-friendly domain names and computer-friendly numeric IP addresses . DNS is an Internet protocol and distributed database.
Here’s how DNS technology works:DNS comprises three components: the name server, the resolver, and the domain.
The hierarchical tree structure has these functions:
Take for example, the domain name www.abc.com.my. The Internet naming
hierarchy for this domain is:
.(root) | my | com | abc | www
At the top of the DNS database tree are what are called root name servers. Each root name server knows the IP addresses of the name servers handling the top level domain names.In our example, the top level domain name is .my. If a querying name server would like to find out the IP address of www.abc.com.my:
The process is graphically presented below:
Example Query: What is the
numeric address (IP address) of a machine with the hostname www.abc.com.my?
Example Response: 192.228.180.200
. (root) name server ^ / v remote name server <----> .my name server - sends query to other name server - gives response to client <----> .com.my name server ^ ^ | \ | v | abc.com.my name server v remote DNS client (resolver) - sends query to name server
Why are name servers required?
Every domain name has name servers that handle queries for its information or records. What’s in a name server? It contains one or more DNS databases to store Internet hostnames and their associated IP addresses . DNS records need to be maintained by people.
Name servers are queried by various programs and other name servers to convert domain names into IP addresses all day long. Each name server, called a primary name server, usually has a back-up server, called a secondary name server, so that this can be done uninterrupted. Both primary and secondary name servers hold the authoritative data of a domain name.
If you wish to receive e-mail from the Internet you need to have a Mail Exchange (MX) record for your domain name in your DNS database. There are two ways to get name servers for your domain name:
What’s a secondary name server?
| .my | the top-level
domain name for Malaysia (see above)
|
| client | a computer
that dials into a network and uses the services of another computer (called
a server). Each client has a unique IP address, either a permanent one or
one that is dynamically assigned to them each dial-up session
|
| DNS (Domain Name System) | technology
that allows domain names to be translated into IP addresses
(see above)
|
| domain name | a textual
address pointing to a host machine on the Internet, e.g. www.abc.com.my;
it identifies one or more IP addresses (see
above)
|
| domain name database | this is
the database of domain names kept in the name server
|
| handle | This is
a pointer that enables a program to access a resource; it’s also a nickname
used for identification, so that information can be quickly located (see
above)
|
| host | A computer
that is attached to a network such as the Internet. Hosts allow users on
client machines to connect and share files
or transfer information
|
| host machine | the machine
that contains and maintains a database of domain names
|
| hostname | the name
given to a host computer
|
| in-addr.arpa | the Internet
uses a special domain to support gateway location and Internet address-to-host
mapping. This domain begins at IN-ADDR.ARPA. The intent of this domain is
to facilitate queries to locate all gateways on a particular network in
the Internet. It is also meant to provide a guaranteed method to perform
host address to hostname mapping
|
| IP | Internet
Protocol is the mechanism being used in the Internet to route packets of
information from network to network (see above)
|
| IP address | the address
of a computer on the Internet; it appears in numerical form, e.g. 192.228.180.200
(also known as network address) (see above)
|
| IP address, allocating | each client
and server on a network must have a unique IP address. Clients either have
a permanent address or one that is dynamically assigned to them each dial-up
session
|
| ISP (Internet Service Provider) | a service
provider that provides Internet access and other value-added services; in
Malaysia, JARING, for instance, is an ISP
|
| label | a component between the dots in a domain name. For e.g. in www.abccompany.com.my, www, abccompany, com and my are all labels |
| name server | servers
that store domain name information or get domain name information from other
name servers and store them temporarily in caches to eliminate unnecessary
network traffic (see above)
|
| network address | also known
as IP address
|
| personal domain name | MYNIC defines this as a third level domain name that can be registered by individuals only, and is meant only for personal use |
| primary name server | the main
name server of a domain name (see above)
|
| protocol | a format
for transmitting data between two devices
|
| record | a group
of units of related data about a subject; a group of records makes a file
|
| root | the top
of the Domain Name System hierarchy
|
| root server | the machine
that contains a database of all top-level domain names
|
| resolver | a DNS client
that queries the name server to resolve an Internet hostname
|
| second level domain | in the
Domain Name System (DNS), the next level of the hierarchy underneath the
top level domain. In a domain name, that portion of the domain name that
appears immediately to the left of the top-level domain. For example, in
this domain name www.abc.com.my, the second level domain is com.my,
whilst in the domain name www.abc.com, it’s abc.com
|
| secondary name server | a server
that acts as an alternative to the primary name server,
and contains the same information (see above)
|
| server | a computer
that provides services on a network to other computers (called clients).
Each server on the Internet has a unique IP address, to which one or more
domain names refer
|
| third level domain | in the Domain Name System (DNS), the next level of hierarchy underneath the second level domain. In a domain name, that portion of the domain name that appears to the left of the second level domain. For example, in this domain name www.abc.com.my, the third level domain is abc.com.my. In Malaysia, it is this third level domain that can be registered with MYNIC |
| TLD (top level domain) | in the Domain Name System (DNS), the highest level of the hierarchy after the root. In a domain name, that portion of the domain name that appears furthest to the right. It usually refers to a country, such as .my or .uk, or a generic name such as .com |
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