13 June 2011

Configuration of an Instar Webcam and Linksys Router for Intra- and Internet (DDNS) Access

So, here is the problem at hand: I've bought myself an Instar 3010 webcam. The latter connects to my home WLAN. For practical reasons, you want

  1. to have a static IP address inside your network so that you can access the webcam always via the same address - like http://192.168.1.90 - and do not have to scan through the current DHCP table to find the webcam's IP address assigned by the DHCP server (which could change everytime you boot one of the devices), and
  2. to have a fixed address that allows you to access the camara from outside your home network; this means that you need
    1. to configure your router / firewall of your router to allow external access for that particular device (identified by the static IP address defined under 1.) via a dedicated port, and
    2. to set up a DDNS service like dyndns.org.

I'm using a Linksys WAG120N router. What I'm explaining below should work for most Linksys routers. Actually, I've also some Linksys WRT54G routers whose admin UI is basically the same. Furthermore, I believe that the infos below can be easily transferred to most other routers too.

Step 1.a.: picking a static IP

What I'm describing here is basically taken from the instructions on this website. Follow these steps:

Pick an IP address within the range of your router BUT outside the range of the DHCP server. Linksys routers are per default configured so that

  • the router itself (gateway, DHCP server etc.) have address 192.168.1.1, and
  • the DHCP server assigns max. 50 addresses starting from 192.168.1.100 to 192.168.1.149.

Consequently pick an address outside those ranges, e.g.
  • 192.168.1.2, or
  • 192.168.1.90, or
  • 192.168.1.200
Let's assume that we pick 192.168.1.90.

Step 1.b.: setting the static IP

Now

  • go into the admin UI of the Instar webcam,
  • namely to Network
  • and there to Basic Network Settings.
  • Uncheck Obtain IP from DHCP Server
  • and fill the address fields as shown:
For later, it is important to pay attention to the Http Port setting - here 80 - as this port needs to be released for external access in association with the address 192.168.1.90. See step 2.a.

Step 2.a.: port forwarding

As mentioned: now let's configure the Linksys router to allow external access via port 80 to the device under address 192.168.1.90. To that end

  • go to Applications & Gaming,
  • and there to Single Port Forwarding,
  • create the following entry

Step 2.b.: DDNS setup

First, I've set up an account with dyndns.org, namely the free service. Here is an example to acquire a dynamic external domain name thomas-webcam.dyndns.org:

With this, you can return to your Instar webcam's admin UI. Remember that you should now find it under http://192.168.1.90 as defined above!

  • go to the Network menu,
  • go to DDNS Service Settings,
  • under Third Party DDNS choose dyndns.org as the DDNS Service,
  • add the entries as indicated; qwertz is the user that you have created with dyndns.org:
  • Go to Network, there to UPnP Settings and enable Using UPnP to Map Port. UPnP should also be enabled in your Linksys router (which it is by default).

You can check if things have worked out alright by going to your webcam's admin UI, to the System menu and there to Device Info. Under DDNS Status you should read something like DynDns Succeed http://thomas-webcam.dyndns.org. You should now be able to access your webcam via http://thomas-webcam.dyndns.org from outside your home network.

Please leave any advice, hints on what can be defined in easier way etc. as comments!