Official ObjectGraph Blog

Thursday, September 28, 2006

Developing Image Authentication Control

I just start developing another ASP.NET Control that allows users to authenticate via text rendered on a image.

This is my Goal:

  • Easy to read
    • Eliminating ambiguous letter such as o,O,and 0.
    • Simple Alphabets and Numbers
  • Hard to crack
    • Changing color
    • Drawing random lines
    • Drawing random dots
    • Rotate / Transform the characters
  • Quick to generate
    • Matrix Operation using Unsafe code(?)

OK, this is very regular way to implement this kind of control, so I was thinking of the future extention:

  • Like KittenAuth ?
  • Voice support
  • WebService (SOAP/WSDL)

KittenAuth is interesting approach to increase the security level. It shows a buch of pictures and a user selects which one looks like purr animal. In version 2.0, it is mixing the kind of animals too.


posted by Kiichi Takeuchi at 8:50 PM | 0 comments |