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Domain Name Services
Explained At Last!
Basic DNS
The Internet uses a distributed naming system called the Domain Naming System (DNS). DNS allows us to
refer to computers by host names as well as by Internet Protocol (IP) addresses.
IP addresses are hard to remember and are inconvenient to use. DNS allows us to use host names and domain
names which can resolved to IP addresses. DNS servers translate host names and domain names (for
example, www.cachecow.tv) to an associated IP address (for example, 192.168.1.10.)
For example, Cache Cow Web Networks has registered the domain name “cachecow.tv©” for use by our servers
“mail.cachecow.tv”, “www.cachecow.tv” and others. The host names “mail” and “www” represent different
servers registered in the same domain.
A domain name is a computer name suffix shared by a group of computers in the same organization. A
domain name should be associated with an IP address through a Forward Lookup record. Domain names are
organized in a hierarchy; this hierarchy includes your company or server name, and a country code (for
example, .uk or .ca) or a top-level domain (for example, .com or .edu).
A Web site on the server is created with one IP address, one host name and one domain name that together
establish the identity of that Web site on the Internet.
Each domain name requires a primary domain authority on one DNS server. A secondary DNS server acts
as a backup to the primary. DNS information is configurable only on the primary server, and not on the
backup server.^ back to top ^
A Brief History Of DNS
In the 1960s, the U.S. Department of Defense Advanced Research Projects Agency (ARPA, and later
DARPA) began funding an experimental wide area computer network called the ARPAnet. The ARPAnet
used a centrally administered file called HOSTS.TXT which held all name-to-address mapping for each host
computer connected to the ARPAnet. Since there were only a handful of host computers at the start,
HOSTS.TXT worked well.
When the ARPAnet moved to the Transmission Control Protocol/Internet Protocol (TCP/IP) suite of
protocols and become known as the Internet, the population of the network exploded. HOSTS.TXT became
plagued with problems, namely
- Traffic and Load
- Name Collisions
- Consistency
A replacement for the HOSTS.TXT file was needed. The goal was to create a system that solved the
problems inherent in a unified host table system. The new system should allow local administration of data
and also make that data globally available.
In 1984, the architecture of a new system called Domain Name System (DNS) was designed and is the basis
of the DNS service used today on the Internet.
DNS is a distributed database that allows local administration of the segments on the overall database. Data
in each segment of the database are available across the entire network through a client-server scheme
consisting of name servers and resolvers. ^ back to top ^
What is a DNS Record?
People are much more comfortable dealing with names rather than strings of numbers. A domain name such
as “cobalt.com” is much easier to remember than the IP address which consists of four octets of numbers
such as 207.91.131.30. Domain names must be registered with Root Domain Registration Service, such as
Network Solutions, Inc. (www.networksolutions.com)
Computers, on the other hand, prefer numbers to names. Since computers have the final say when a user is
looking for a company Web site, a mechanism is needed to convert the human-friendly domain name to the
computer-friendly IP address.
DNS records on a DNS server perform this function. The records translate a domain name to an IP address;
a record equates a domain name such as “cobalt.com” to an IP address such as 207.91.131.30. Once the
domain name has been converted or "resolved" to an IP address, then (and only then) can the user connect to
your Web site.
Without DNS and domain names, the user would be required to remember the IP address of every site they
wanted to visit. With DNS servers and DNS records, customers and their software can easily remember how
to get to your site.
Who Manages the DNS Records?
Your DNS records can reside on any our servers that has the DNS service enabled. Our administrator can easily configure Lightning Quick Server© to act as a DNS server. To provide DNS service,
InterNIC requires a site to maintain both a primary and a secondary server. Ourr Cobalt servers can act as the
primary server and a DNS server from your Internet service provider (ISP) can act as the secondary server.
^ back to top ^
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