In order to transfer files and be sure that they were not compromised on their way to their destinations a method of ‘checksumming’ the file’s content can help. Under Linux the tool is called ‘md5sum’. Here is how to use it. For example to check the integrity of the downloaded Ubuntu Linux .iso file.
The result would then be for example:
Then verify this MD5 checksum against the one provided by the Ubuntu web site and they both should be identical.