When a student downloads a Resource or Project start file from their assignment page, SIMnet injects additional data, inaccessible to the user. This is referred to as the user’s Unique Signature. That additional data is an encrypted set of keys used to uniquely identify the student and start file. Each downloaded start file has at least one unique signature. Depending on the size of the start file multiple distinct Unique Signatures are injected into various locations of the file. Injecting multiple Unique Signatures prevents tampering with the Unique Signature. The student must upload a file that contains the same unique signature data that was included in their downloaded file. When the student uploads or submits their assignment for grading, the file is automatically reviewed for these Unique Signature elements before the assignment is accepted. If the data matches the student’s information, then the file is graded. If the Unique Signature data does not match, the student receives an Academic Integrity Violation flag or will not be able to submit their file depending on the instructor’s set preferences. A submitted file that doesn't contain any Unique Signatures is not accepted.