mfleck

Greetings, I am a new member here, so please excuse if I've posted this in the wrong area.  And while I searched for this topic I hope I'm not repeating something you've already covered... I'm in the early planning stages of a project which will be written almost entirely using php to interface with a mysql database on a hosted server.  It will be critical that data be entered only from known sources.  In other words, its not enough that Mary is able to authenticate with user name and password, we also want to be sure that she is using a machine that is known to the system, not from home or elsewhere. Although I have a lot of experience coding in php there's nothing popping into mind as a good way to accomplish this.  Ideas?