Plagiarism Checker

Hi,

I've search throughout the internet and was looking for a plagiarism checker plugin for Moodle.

I understand most of them explain and suggest to use Crot.

I did try it by unfortunately MS Application Key is the problem.

They do not support Crot anymore.

Is there any FREE plugin that works just like Turnitin with Moodle 2.6+?

I need it to check the assignment submission by students.

Thanks.

Kai