Data Insertion Protection?

[eluser]jamgood96[/eluser]
There's a basic login for viewing the monitoring system, but as far as the micro-controller (Arduino) it's only able to do very basic HTML functions, and post/get is one of those.

Right now I have a controller setup to take a post request and insert that data into the database. The Arduino sends a basic HTML request with the proper header to this controller and posts the data (i.e. power or energy consumption). This then gets processed an inserted into the MySQL database.

So you can see a login for the Arduino to post info won't work. Does it do me any good for the controller to require a specific passphrase be posted along with the data? That way the Arduino can post the data and the passphrase. Does this provide any real security?

Thanks!