A brief overview of Dynamic DNS Service; what it is, how to configure it, and some common surveillance applications.
Setting Up a Dynamic DNS Service
Today I am going to be going over Dynamic DNS servers, including what it is. How it is set up and how it is commonly used with surveillance installations. DNS stands for Domain name system, and is used to resolve a specific into an IP address. Similar to how you might use the yellow pages to find the phone number for a specific business. This is how you are able to type in google.com and pull up Google’s homepage. For example if I type in geodemo.apexcctv.com in command prompt that name will resolve itself into 192.168.1.20 and I can open our GeoVision demo by typing that IP address into a web browser, which is what most of my clients will do, or because I have a friendly name configured I can type in geodemo.apexcctv.com and I get the same page on the same server I can sign in either way, and view the cameras move them around or whatever the DVR would allow me to do under normal circumstances.
Let’s say my clients IP address is 220.127.116.11, I believe this is my current IP, and I can find out by going to whatismyip.com from any computer and it will tell me what my public IP address is. Regardless I setup all their cameras, their digital video recorder, deal with any port forwarding and any networking that needs to be configured. They can then go to a web browser and view their cameras by typing in this IP address 18.104.22.168. I’ve got them all set up and they are happy and everything works perfectly for a while, but then for whatever reason the ISP changes their IP address and when they go to 22.214.171.124 they get a page not found error because that address is no longer valid. This is where dynamic DNS comes into play, dynamic DNS services will host a friendly name for their cameras or DVRs so when they use that friendly name they can get to their cameras just like with www.google.com.
The benefit here is that when the IP address changes, the dynamic DNS tracks the change very quickly and apexdemo.dyndns.org will always resolve to the same address. There are lots of dynamic DNS services available and most of them offer a basic free service. I’ve been using dyndns.org for 10 years without issue, so I’ll use them as an example. Here I am at dyndns .com, once again this is a service I’ve been using for a long time and I highly recommend them they of course offer a free dynamic DNS service scroll down to services click on free dynamic DNS to start the process.
We’re going to go and click on dyndns.org, it’s just their standard domain name and so whatever I put in the first box is going to become the dynamic DNS address so I’m going to put in apexdemo as a quick test. I’m going to host with this an IP address; it’s just the standard way of going about it. It’s already detected my IP address so I’m going to allow it to use that one. I don’t need any mail routing so I’m going to just create this. So now it’s essentially finished, if I go to command prompt and ping that address it should already be resolving and now immediately like that I can use this name browse to my DVR.
The important thing I have to do now is set up a dynamic DNS client. So DVR’s like the GeoVision dvr have one built in, I believe AVerMedia has one built in and most of the Vivotek have them built in. It does have to be configured, in order to get to DynDNS’s free client go back to their homepage and click on support, I use the DynDNS updater for windows. It will automatically post an update about every week or so because these free accounts will expire if there isn’t an update to the IP address. If you have an IP that changes a lot installing this on the DVR is fine, as long as it’s on a computer on the same router.
Here it is on my desktop and this is a pretty standard installation. There are a couple important details, we want this to start with Windows, so it keeps running, and runs as a windows service, so it runs in the background; which is the default configuration. Click next and check the checkbox, this basically prevents it from running as a windows application like outlook, so at the end of the day the user doesn’t really know this is on their computer. It’s not interrupting your system or slowing down your computer and running over and over and over. Click next I’m going to use the default installation and it installs pretty quick. I’m going to run the updater and I’m just about finished all I’ve got to do is put in my username and password for the DynDNS website and it found my current IP address, shows the status of the updater, my user name and any hostnames I have registered for the account. So I’m going to check the host and click apply and now it’s showing me that it has updated and the last update was today. You can click on advanced and there’s a few features I turn off for resource reasons, usually the automatic update and the display because I don’t need it down in the tray all the time, it’s more of a set it and forget it application.
Let’s look at a computer off my network and ping apexdemo.dyndns.org or go to internet explorer and type that in and it’ll send you to the DVR. Now I’m outside the network and this ws2 is one of our web servers and it’s in a completely different physical location. I can log in as a guest, feel free to check this out on your own, the frame rate isn’t going to be very high on your video because I’m doing this from offsite like if I were doing this from home or a hotel. In effect though this is going to work at all times no matter what my IP address becomes this name apexdemo.dyndns.org will always take me to my DVR.