Dynamic DNS is used to assign a persistent domain name to a device.  The device allows to update Domain Name System to a point to a changing IP Address in automatic regime.  Example of setting up Dynamic DNS service on no-ip.com:

• Register on no-ip.com or login using an existing account.
• Create a host on no-ip.com: "Add Host". Host parameters: Hostname - name of host , type: DNS Host (A), Ip Address: do not change, it will be automatically updated by device
• Go to web-interface of monitoring device "Preferences"->"Network".  Select "Enable DynDNS".  Select service: No-ip (www.no-ip.com), type in Login, Password and Hostname which you put in no-ip.com.  Save settings "Save".
• The device should update the IP address for the Hostname host after 1 minute.  You can check this in the no-ip.com service. After some time the service will match IP address and Hostname.
•  Using the Hostname in the browser open the web-interface of the device.  If the host does not work try to use IP address which will install the device on the no-ip.com service for the Hostname.  If IP address does not work as well, this can happen if port 80 is closed and does not allow to host a server in your local network.