the business allows customers to apply for authorization. Only when authorized can customers access our website on the computer applying for authorization. Originally, we wanted to use js to obtain the mac address of the client, but this js can only be implemented under ie. Companies want to achieve this function under mainstream browsers. So, the acquisition method of mac address is not good, so I want to generate a unique identifier on the client instead. That is, when the customer applies for authorization, he will generate a file locally with his unique identifier, and every time he logs in, he will insist that the contents of this file are consistent with those in the database, but this js is not feasible either. Non-ie browsers cannot get the permission to read the file, so is there any other way to generate a unique identifier?