Dynamic DNS Demystified
By Al Williams
When I first got started in this business, computing was a lot less accessible than it is now. I remember driving 60 miles to reach the closest computer store. Nowadays, of course, you can buy computers almost anywhere.
Networking has seen a similar transformation. There was a time when getting connected was an arcane art; in 1969 it was a big deal that a computer at the University of California, Los Angeles had a connection to one at SRI International in Menlo Park. Today, there is a high-speed fiber optic network running through my backyard (literally—they all but dug up my fence to put it in), and you can buy broadband network hardware at any office supply store.
However, there's usually a catch: Broadband providers frequently don't offer static IP addresses. Some services (notably DSL) connect using PPP over Ethernet, which routinely reassigns your network address. My cable modem, on the other hand, uses DHCP to obtain a dynamic address. Some providers will offer you a static IP for an additional fee. In other cases, there is no way to get the provider to assign you a permanent address at all.
Why should you care about having a static IP address? If you're only surfing the Web, you probably shouldn't. However, if you plan to use your broadband connection to collect remote data, accept videoconference calls, or host a server, then you'll want some way for people on the Internet to find you.
Redirection Made Easy
The domain name service (DNS) was created to make it easier to locate machines on the network.
