Your IP address is the web address (or URL) you would use to access your camera externally from the Internet and should be used in situations where you find you have been given a dynamic IP address from your DSL provider (ISP).
Dynamic IP vs Static IP
When the Internet was originally designed they did not see the need to have an endless amount of IP addresses and today the number of addresses available are fast running out. One way to get around the problem is to share IP addresses and this is what your Internet provider does. To save using all of their allotted IP addresses they save a percentage to use for sharing. The shared addresses are then allocated to customers as and when they log in to the Internet with their computer. This is known as a dynamic IP address and this allows you to use the Internet but makes it very difficult, even impossible to access your computer from another location on the Internet. Using a telephone analogy, think of it as calling from a pay-phone, you can make a call out when you need to but you don’t really care what number you are calling from.
The flip-side of this is when you request a static IP address from your Internet provider. This gives your computer a permanent address on the Internet allowing you to access the Internet, as well as contact your computer from anywhere else on the Internet. Using the telephone analogy, this is like have a telephone in your apartment. You have a permanent number and can make outgoing calls as well as being able to recieve incoming calls. Of course a static address is the best one to have but you may find it will cost you a little more from your Internet provider if you request one.
Every website on the Internet has it’s own unique IP address and without these addresses the Internet grind to a halt as our computers don’t understand what a ‘Google’ is or what a ‘Microsoft’ means. Computers use numbers and where the Internet is concerned, IP addresses. Now we couldn’t possible remember the IP address for every site we visit. We humans we find it a lot easier to remember words like www.google.com instead of numbers like 126.96.36.199. A DNS server sits on the Internet and serves IP addresses for all the websites we visit so when we type www.google.com it looks up its huge DNS tables and translates that address into it’s corresponding IP address so our computers can understand it. That’s all they do.
Dynamic DNS doesn’t wear a cape or have super strength, no, Dynamic DNS is a service we can use to track our own Internet address. There a two main benefits. 1. You give your camera a meaningful name instead of remembering your IP address. This makes it easier to remember if you access your camera frequently from different locations across the Internet. 2. Behind this name the Dynamic DNS service automatically knows when your Internet provider changes your IP address. This is achieved by the device configured for use with the service sending outgoing messages periodically updating the DNS tables with the current IP address.
Do I really need a static IP address?
For most users a Dynamic DNS address will be fine. We use them a great deal and they are almost as reliable as having a static address.
Of course there is always a chance the service can go down so for any mission-critical security applications I would advise you get a static IP address from your service provider. It removes another potential problem from your network setup.