When a reader requests to open your PDF document, the user should generate a local key in his/her computer before authorized. This local key means the identification of the device. Only this computer could open and get access to the PDF document.
As the PDF owner, once you have received the local key from the user, you should start authorizing process, encrypt your document and lock the users computer. The produced new key is protected by AES encryption and random algorithms technology. The key will be exported to a new txt file.
After the step 2, the PDF owner can deliver the new key to the user. The user should use the built-in PDF viewer our program provides to view the document. Click Open PDF button and enter the shipped key and then select the authorized PDF to open. Our viewer only allows reading.
Screenshots Secret PDF