[dzp111]

I googled to find out what the purposes and usefulness of Static IP Address are but it's all jargon to me.

If you're familiar with my other thread concerning a small business in the making, this question is a supplementary to that.

The business in question will have a new iMac at the front desk, a fairly new iBook in the owner's office and a new Lexmark 4 in 1 wireless printer. We intend on networking all 3 devices.

Is static IP important? Useful? But my main question is 'What is it'?

Could someone explain to me as if I were a 13-year old?


Thanks.

[besson3c]

A static IP address is sort of like having a mailing address that doesn't change that people can use to contact you via the internet. There are still ways to do so without having a static IP address, but a static IP address makes this pretty simple.

If you won't be hosting any internet services that people from outside your network will be connecting to (say, a web server, mail server, FTP, etc.) you don't need a static IP.

[ibook_steve]

To understand a static IP, you have to understand what a dynamic IP is as well. The IP (Internet Protocol) address is the unique number used for any computer on the Internet to access your computer. Each number on each computer has to be unique.

A static IP is an IP address where you "set it and forget it", meaning you manually enter the exact address and other required information (default gateway, name servers, etc.) in order for your computer to access the Internet and for other computers to connect to yours, and you don't change this information and it never changes. As mentioned, static IP addresses are usually used by servers (web, email, etc.). Why? Because the location of a server on the Internet should not change over time. The location needs to be fixed so that you can always access it no matter what at the same address. This is where the Domain Name Service (DNS) comes into play. DNS associates a human-understandable name (google.com) with a static IP address that doesn't change (66.102.7.99). That makes it easy for everyone to access the server.

A dynamic IP address, as the name implies, is an address that can change. A good example of dynamic addressing would be when a modem (cable, DSL, old dial-up) connects to an ISP. The ISP selects an IP address from a pool of addresses and gives it to you when your modem connects. If you were to later disconnect and then reconnect, there's no guarantee you would get the same IP address from the pool. That's why the address is dynamic. If you had a static IP, you'd always get the same IP address whenever you connect.

The problem with a dynamic IP on a server is that normally, you can't use it with DNS. DNS does a one-to-one matching between a domain name and an IP address. If that IP is constantly changing, that association can't be made. That's why there are services like dyndns.com that can track the changes to your dynamic IP address so people can continue to access your server, but I'm not going to get into how that works.

Dynamic IP is usually a function of a service called Dynamic Host Configuration Protocol (DHCP). A DHCP server is what hands out the dynamic IP addresses, making it easy for a user to connect without having to manually enter a static IP address on their computer. If you have a router at home, chances are you have DHCP enabled so that addresses are handed out to all the machines on your network.

There's a lot more to learn about this, such as why routers use 192.168.x.x or 10.0.x.x addresses and how this saves IP address space, but I think Google and Wikipedia should be able to help you out. If you have more specific questions about something, just let us know and we'll try to help!

Steve

[olePigeon]

172.x.x.x is the third private network range.

[Spheric Harlot]

In short:

Static IP means your address remains the same to the outside world, always.

Dynamic IP means your address may change anytime your internet connection is dis-/reconnected.

Do you need the machine to be permanently, constantly, and reliably available TO OTHERS via the internet? If so, static IP is a good idea.

If not, don't worry about it.




If you need this basic functionality, but your livelihood doesn't depend upon 100% reliability, then there are free services that "lend" you their domain name and forward the connection to your dynamic IP. This requires a program to run on your machine, that keeps the service updated about the current address. For example, if you used the free DynDNS service, your server would then be reachable under yourusername.dyndns.org.
This is fine for administration and most other things, but you depend upon 1) the software running, 2) the software keeping the service's records updated, and 3) the service working properly.

Not an option for corporations.

My hunch is that you'll be setting up your website on a hosting company's servers, and that whatever remote administration you'll be doing (if you want to even set up access, which is always a risk) will be amply served by dynamic IP.

[olePigeon]

Some useful things you can do with a static IP:

Webhosting: Run your own website with no restrictions.
eMail: Similarly, run your own email server.
VPN: Connect to your home network from anywhere.
Games: Run your own game server

I'm sure there are tons of other ideas.