MIONET is not a program per-se it is a service.
It let you find your Network and connect to the specific device.
If you want to do it on your own, first you have first to find a way to connect to your Network.
This page describe few options,
http://www.ezlan.net/myip.html
Then you have to be able to Route to the device.
When you access a device that is on a network behind a Router from the outside. The Routing is done by opening the port of the application used toward the Device.
Example: if you want to access with ftp client that uses port 21 you open port 21 toward the IP of the device.
Since your device is a NAS (not a computer), you cannot install on it a running programs.
However, the MyBook has an ftp server installed.
Give the My Book a local static IP and open the port that is uses for the ftp through the Router's Firewall toward the static IP.
Use a client ftp to connect from the outside to the NAS.
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The above is a general description of a solution and does not take care of security.
You have to find a way to secure such an adventure as well, may be Hamaci can be used to provide security.