So, if the names are not the same. How would you then know that file_1 is equal to file_2?
If you do a md5sum on all the files and create something like a hash (eg. file_1: md5sum output), then compare the md5sum. If the md5sum are the same, then the files are the same? But what the chances that two files have the same md5sum but in reality they are not the same.