"What
is DNS?"
DNS
stands for Domain Name System. It's a database system used
throughout the web to map friendly names into IP addresses. A DNS
server runs special software to keep track of machine names, web site
names, email servers, nicknames, and IP addresses of servers or host
machines attached to a particular network, making it possible to
access an Internet site by using (with ourselves as an example) CASDNS.net
instead of it's IP address 208.33.128.50. DNS also supports
separate mappings between mail destinations and IP addresses, and a
number of other complex functions.
When
you register a domain name, you are asked to supply the names and
addresses of two DNS servers where you will have your site
hosted. Every web hosting service has its own DNS servers, and
will supply the information to you on request. It is on these
DNS servers that all of the details associated with addresses for your
site, your email, etc. are entered and stored. If you ever
change hosting services, you can modify your DNS server information my
submitting the new information via our modification
form.
As
an example, when a person types a domain name into their browser, a
query is sent to the InterNIC (government) root servers. The
answer from the root refers the request to the DNS servers you specify
at registration (or latest modification). Those servers in turn
send the request to the IP (numeric) address of your web page, which
is then displayed in the browser. The whole DNS process usually
takes only milliseconds.
If
you have a computer running web server software, with a permanent
connection to the internet, and with it's own static (unchanging) IP
address, you may want to run your own DNS server using your own domain
name. Affordable software is available on the web via download,
the simplest starting at under $100. If you wish to do
this, you will need to register your server, which is also called a
host. Customers who have registered their domain name through
CASDNS may register their hosts here via our Host
Registration Form.
If
you have an internet dedicated web server (as above) and don't feel
comfortable with programming your own DNS, CASDNS can provide DNS
services for domains registered through us for $20 per year. You
can select that option on our domain
name registration form.
Excellent
tutorials and information on DNS on the web may be found at sites such
as
http://michael.iserver.com/dns/
http://www.ludd.luth.se/~kavli/BIND-FAQ.html
http://www.verinet.com/dns/
http://www.dns.net/dnsrd/
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