The domain name system (DNS) is one of the many services that support a user's connection
to the Internet from an IP network. It functions as the "name keeper" for all the
important resources such as web servers and FTP servers. DNS allows the user to
remember the friendly name, like www.charter.com, even though the network needs
to know the numeric IP address (e.g., 188.8.131.52).
The DNS is a worldwide network of servers (each primary server has a secondary server
for security and redundancy) that maintain a distributed, shared database mapping
the name and corresponding IP address of every publicly accessible device on the
Internet. The mapping of a domain name to a number and a number to a domain name
makes the web more market-oriented and easier to navigate.
- DNS is structured hierarchically, starting at the 'root' (represented by a period
"." or dot).
- Top-level domains or TLDs include .com, .org, .gov, .edu and .net, for example.
The top-level domain is the right-most 'dotted' label in a URL (uniform resource
- Other mid-level domains are the country-specific extensions (if used), host level
domains, which includes charterbusiness.com, for example.
On another level are the resource domains, www or ftp, for example.
Charter Business hosts both the primary DNS server and the secondary DNS server.
The primary DNS server is the only one that can be both read from and written to
for domain information. The secondary DNS server is the backup and is a copy of
the primary DNS server database.
The different kinds of DNS records that a DNS host server typically includes in
the database are:
- A Records: map the URL to the IP address
- MX Records: identify the name and IP address of mail servers
- NS Records: specify other DNS servers in the same zone
- Cname Records: allow use of an alias name that resolves to the A Record resource
Charter Business maintains the following DNS records on its DNS servers: