X-NetStat 6.0 Documentation
Last Revised: May 2021
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IP Addresses and Hostnames
An IP (Internet Protocol) address is a numerical sequence that uniquely identify
a computer, or other networked device, on a network such as the Internet. To be
able to use the Internet, your computer needs an IP address so that network
traffic can be directed to and from it.
When you log on to the Internet,
your Internet Service Provider (ISP) typically assigns you an IP address for
your current session. If you use a dial-up, you usually receive a different
address each time you connect. If you connect to the Internet from a local-area
network, like you might at work, or through a cable modem or DSL line, you might
have an IP address permanently assigned to your computer.
Anytime you
send an e-mail, access a Web page, or try to send or gather other information to
or from the Internet, your Internet application communicates with a server via
its IP address. IP addresses are usually formatted by means of four numbers from
0 to 255, separated by dots. A typical IP address might be "209.94.162.45".
Since it is difficult to remember arbitrary strings of numbers, and an IP
address for a given computer can frequently change, textual "hostnames" are used
in place of numeric addresses. Hostnames are used to make addresses easier to
remember, and to continue to identify a specific computer even when its IP
address changes. DNS (Domain Name System) is the Internet function that provides
"hostname resolution", which translates textual hostnames into numeric IP
addresses.
The Domain Name System is what enables you to type in names
(such as "www.freshsoftware.com") instead of numerical IP addresses. When DNS
translates hostnames into their numerical counterpart, the process is usually
transparent to the end user. When an Internet application encounters a textual
hostname, it sends a request to a DNS server. The DNS server will then respond
with the IP address associated with the textual hostname, or it will signal an
error if it cannot find an associated address.