Question

A file is currently compressed in its local file system. For security reasons, the file is required to be encrypted. The file can be both compressed and encrypted. True or False

Answer 1

True. An encryption scheme doesn't care what it is encrypting, be it compressed or uncompressed.

Note that an encrypted file will look like random data to most compression algorithms, so it makes sense to first compress, then encrypt, to get the maximum efficiency from the compression.