You suppose that you have activate the DDNS in your Router.
and that the name of your host name is the following:
http://sample.dlinkddns.com
With this url you can access in your router by remote network.
Now you suppose that you have a ipwebcam (192.168.1.48) on port 8585 and you have open the port 8585 in your Router in this way:
Now you can see your ipwebcam from remote network typing the following url:
http://sample.dlinkddns.com:8585
but if you try to connect from your local network you will have an error.
The only way to see the ipwebcam from your local network is the following:
http://192.168.1.48:8585/
and that the name of your host name is the following:
http://sample.dlinkddns.com
With this url you can access in your router by remote network.
Now you suppose that you have a ipwebcam (192.168.1.48) on port 8585 and you have open the port 8585 in your Router in this way:
Now you can see your ipwebcam from remote network typing the following url:
http://sample.dlinkddns.com:8585
but if you try to connect from your local network you will have an error.
The only way to see the ipwebcam from your local network is the following:
http://192.168.1.48:8585/
If you want see your ipwebcam from your local network using the DDNS the solution is the following:
Add the "Application Rule" in your route in this way:
now you can use the host name (DDNS) in your local network: