The GridPic™ feature allows a user to upload a custom image of their choice which will be displayed during the log-in process. This image offers protection against phishing and other attacks of a similar nature.
Where GridGuard™ differs from other authentication solutions is in its ability to allow users to upload their own image instead of just choosing one from a stock set of images. In addition to being more recognizable and easier to remember, it also makes it harder for a phishing site to replicate the look of your customized log-in page.
The Add-On feature allows the user to specify an 'add on' number that will be used to enter their GridCodes™. The user will add the value of the 'Add-On' to the numbers displayed in the corners to determine the actual GridCode™ numbers. This offers an additional layer of security and for those situations where an observation based attack is likely.
For example, if the underlying password is 'Gr1d', and the user had selected the top left corner, then for the cells shown on the right, normally their GridCode™ would be '5339'. But if an 'Add-On' of 3 were set for the user, then they would add 3 to the value of each GridCode™; so for the 'G', instead of entering 5, they would enter 5 + 3 = 8, for 'r', 3 + 3 =6, and so on. This would result in a grid code of '8662' instead of '5339'. And as you can see, the number 8 does not even exist in any corner of the cell 'G'!