To this entry did WEB authentication with RSA, the algorithm. The language used was PHP with a MySQL database, what we do in relatively simple, but I was too complicated for me my little experience (very little) with PHP . This code is the main page, which generates "x", choose your "user" and gives you access to a link which downloads a script with which to generate "r", also has a button to "validate" that tells if really you. (These authenticated). Clarification when clicking the Generate button will show a value of "x" random, but the field will empty this is where I fail, you have to add the field to the "X" on hand. By clicking on Send you send a second window where you show your data are generated and whether or not you. Screenshot