ok, I think I have not explained well...
I did not want to install a web server... I wanted the application to work all the time, and "everywhere", so I was talking about "file"
given a pc "server" (eg 192.168.0.123) with a shared folder (eg "share")
the management application write a file for each arduino in the network (eg arduino1.txt, arduino2.txt, etc ...)
arduino # 01 every 30sec reads the contents of the file \192.168.0.123\share\arduino1.txt
arduino # 02 every 30sec reads the contents of the file \192.168.0.123\share\arduino2.txt
etc...
it's possible to do it? ...or is it better to use a Raspberry? 