Linux.com: Getting Started with Dynamic DNS

“Your ISP probably assigns your computer an IP address
dynamically. It means one less thing for the both of you to think
about, but it also puts you in a bind if you need to connect to
your machine from the outside: you can’t locate your PC amidst
those of all the ISP’s other customers. To overcome this obstacle,
you can use dynamic DNS. Here’s how to get started.

“The crux of the issue is that the domain name system was
created with fixed name-to-IP mapping in mind, back in the mid
1980s. IP addresses were static, so the mappings between host names
and IP addresses were static, too. But the early 1990s saw the rise
of dynamically assigned IP addresses, thanks to protocols like
DHCP. Thus some IP addresses were constantly coming and going, but
the nameserver records were not being refreshed to reflect the
changes…”

Complete
Story